Leonardo Times October 2014

OCTOBER 2014

Leonardo Times Journal of the Society of Aerospace Engineering Students ‘Leonardo da Vinci’

page 26

Future of Dutch military air control

number 3

Interview with Commandant, AOCS, Nieuw Milligen

Soviet Lunar Program Interview with Dr. Malenkov

Delfi-n3Xt Mission

Launch and operations of the DELFI-N3XT satellite

DSE Spring 2014

Year 18

Student Design Projects

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Contents Table of contents

Cover articles

Contents

04

Editorial

05

From Leonardo’s desk

06

Current affairs

08

Predictive RANS

Interview with Commandant, AOCS, Nieuw Milligen

10

The economic potential of kite power

12

Delfi-n3Xt

16

Adrestia’s manned fly-by mission to

The Air Operations Control Station in Nieuw Milligen will be closing expectedly in 2018. What does this mean for the Dutch Military Air Control and Air Battle Management? The commander of the airbase, Colonel Henk Ras, shared his vision and plans for the future of air control.

22

Mars

26

03

Future of Dutch military air control

Soviet Lunar Program

18

Internship report

20

LVD - The origins of Airport security

22

Interview - Soviet lunar program

26

Interview - Future of the Dutch military

Interview with Dr. Malenkov

air control

American Space race efforts are well documented but the Russian story is largely untold. Dr. Malenkov, a prominent engineer on a number of Soviet space missions reveals his experiences.

30

RVD - ITAR and the future of European

32

Forward extending flying boom

36

Design Synthesis Exercise Spring 2014

50

Column

12

Space

Advertisement index KLM

15

Dynaflow Research Group

25

Dutch Aviation Group

35

ASML

43

Heerema

51

NLR

52

Fokker

Launch and operations of the DELFI-N3XT satellite In November 2013, the faculty’s second satellite, DELFIN3XT, was launched by a Russian rocket.

The satellite has been developed by students and staff from the Faculty of Aerospace Engineering, Delft.

36

02

Delfi-n3Xt Mission

DSE Spring 2014

Student Design Projects The Design Synthesis Exercise (DSE) is the culminating project for the Bachelors in Aerospace Engineering at TU Delft. Students are required to make a design in the field of aviation, space, earth observation in groups for 10 weeks.

OCTOBER 2014 Leonardo Times

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Editor’s letter Dear reader,

Colophon opment of CubeSats called the ‘Delfi Program’ of the Faculty of Aerospace Engineering, TU

The cover article of this

Delft. On page 12, you can find about the mis-

issue of the Leonardo

sion and its launch story.

Times student journal features an interview

The Design Synthesis Exercise forms the clos-

with the commander of

ing piece of the Bachelor’s program in Aero-

the Air Operations Con-

space Engineering at TU Delft. The students

trol Station, Nieuw Milligen. The base is the

working in groups work on one complete de-

air traffic control centre for all military traffic

sign on basis of knowledge acquired from all

in the Netherlands. The Leonardo Times sat

aerospace disciplines. We feature some of the

down with Colonel Henk Ras about his vi-

projects done by the students in Spring 2014.

sion on the new operational system and the

Many of the projects initiated in DSE projects

future of the Dutch military air control in light

have gone on to actually develop into real en-

of the government’s decision to close the

gineering operations.

base at Nieuw Milligen from 2018 onwards.

The operations will be spread over four differ-

Students from Aerospace Engineering faculty

ent locations. The tasks performed by AOCS

have always been active in international de-

are of critical importance as was the case in

sign competitions and in October, BSc and

March 2014 when Netherlands hosted the

MSc students won two first place awards in

nuclear security summit in The Hague, which

American Institute of Aeronautics and Astro-

was attended by 58 world leaders including

nautics (AIAA) Aircraft design competitions.

the American and the Chinese presidents.

The awards are considered the most presti-

The article gives a peek inside the working of

gious international collegiate contests in the

the organization that goes into handling such

aeronautical design industry. This extends

complex tasks.

a series of wins by TU Delft students in the awards and we will be featuring details of the

This issue also features one of the lesser-

competition in the next issue.

discussed aspects of the space race, the Soviet Lunar program and its history. We inter-

Apart from these articles, I hope you will ap-

viewed Dr. Mikhail Malenkov, a prominent

preciate the many insightful scientific and en-

Russian space engineer and part of numerous

gineering studies featured in this issue of the

soviet space projects in Moscow.

Leonardo Times.

Delfi-n3Xt is the second in line in the devel-

Sushant Gupta

Year eighteen, number 3, October 2014 The ‘Leonardo Times’ is issued by the Society for Aerospace Engineering students, the VSV ‘Leonardo da Vinci’ at the Delft University of Technology. The magazine is circulated 4 times a year with a circulation of 5500 copies.

EDITOR-IN-CHIEF: Sushant Gupta FINAL EDITOR: Jeroen Wink EDITORIAL STAFF: Bob Roos, Jasper van Gorcum, Joris Stolwijk, Jules L’Ortye, Lakshmi Sabbapathy, Lubi Spranger, Nikita Mahto, Prithvi Penumadu, Raphael Klein, Shahrzad Hosseini THE FOLLOWING PEOPLE CONTRIBUTED: Jef Michielssen, Wouter Edeling, Christoph Grete, Jasper Bouwmeester, Vincent Bijsterbosch, Rens Douma, Djim Molenkamp, Tom Pruijsers, Sarah Dutrieux, Dr. Mikhail Malenkov, Elwin van Beurden, Huub Timmermans, DSE Groups and Eugenie Zagrazki COVER IMAGE: AOCS Nieuw Milligen DESIGN, LAY-OUT: dafdesign, Amsterdam PRINT: Quantes Grafimedia B.V., Rijswijk Articles sent for publishing become property of ‘Leonardo Times’. No part of this publication may be reproduced by any means without written permission of the publisher. ‘Leonardo Times’ disclaims all responsibilities to return articles and pictures. Articles endorsed by name are not necessarily endorsed editorially. By sending in an article and/ or photograph, the author is assured of being the owner of the copyright.

‘Leonardo Times’ disclaims all responsibility. The ‘Leonardo Times’ is distributed among all students, alumni and employees of the Aerospace Engineering faculty.

VSV ‘Leonardo da Vinci’ Kluyverweg 1, 2629HS Delft Phone: 015-278 32 22 Email: VSV@tudelft.nl ISSN (PRINT) : 2352-7021 ISSN (ONLINE): 2352- 703X For more information, the website can be visited at www.vsv.tudelft.nl. At this website, the ‘Leonardo Times’ can also be digitally viewed. Remarks, questions and/or suggestions can be emailed to the following address: LeoTimes-VSV@student.tudelft.nl

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Leonardo Times OCtober 2014

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From Leonardo’s Desk

Dear readers, ‘Fulfill the wishes of all aerospace students’. With this motivation, John Leyds set up the VSV ‘Leonardo da Vinci’ seventy years ago. 69 years later, this goal has not changed and is even more important than ever before. For over 69 years, VSV members have been working hard to give their fellow students new opportunities to become the aerospace engineers they aspire to be. This academic year, we will celebrate this history and the future, all together during the Lustrum year.

For the VSV ‘Leonard da Vinci’, It all started 69 years ago in 1945, the aerospace engineering faculty had existed for five years, the second world war had ended and students finally had a possibility to setup their life again. John Leyds decided to not only focus on himself but also help other students from the faculty. Along with three fellow students and the agreement with Prof. van der Maas, he became the president of the first board. ‘Leonardo da Vinci’ was the name chosen to represent the newly formed society. It was a befitting name for the society as da Vinci had a lifelong fascination for the phenomenon of flight and is recognized as the most diversely talented person to have ever lived.

A new society was established and on its way.

As a board member of the VSV ‘Leonardo da Vinci’, I find it pleasing to look back into the history of the society and to get to know the experiences we, as a society, have gathered during all these years. All the activities that are organized by our students today are based on 69 years of experiences. Nowadays, we organize the same activities but bigger and better than before. Starting from September, the 70th board of the VSV ‘Leonardo da Vinci’ will make the Lustrum year better than ever before. With the lustrum theme ‘Up, Up & Away’, the VSV will achieve new heights!

participants. Due to the experiences of all these years, we learned from all these moments and are able to organize a perfect Studytour this September and make all the participants happy without any major hiccups. ‘Valhalla’ takes students to leading aerospace companies in Denmark, Germany, Sweden, Norway and Italy!

After one year of being in the board of the VSV ‘Leonardo da Vinci’, one gets to know the society very well. During the year, we all have been in contact with the history

At the end of August, the freshmen’s weekend EJW took place. During the weekend, we welcomed around 240 new aerospace students to make sure that they get to know each other, the society and the student life in Delft so they can study with a flying start. As the board of the VSV ‘Leonardo da Vinci’, we would like to wish every first year student the best of luck with their studies in Delft.

of the society, the members, members

Only two weeks after the freshmen weekend, the last activity of the VSV will take place, the Studytour. This tradition started in 1946, as the first trip abroad to ‘Salon de ‘’Aéronautique’ the Airshow ‘Le Bourget’. In 1946, they reached their destination with two flat tires, too little money and gas but with a lot of enthusiastic

On behalf of the 69th board of the VSV

of honour, the employees of the faculty and employees of all kinds of companies.

This year we have had a lot of help from all those people and without them, we would not be able to run the society as we did it. Thank you all for the help and we are looking forward to the next lustrum year!

‘Leonardo da Vinci’, With winged greetings, Jef Michielssen, President of the 69th board October 2014 Leonardo Times

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current Affairs

30-06-2014, Kourou, French Guiana

nasa/JPL-caLTecH/msss

August 5, 2014

finaL aTv LaUncH

N

ASA’s Mars rover curiosity has celebrated its two-year anniversary on Mars. During those two years, curiosity almost reached its initial destination Mount Sharp, a high mountain in Gale crater that will most likely hold information regarding the geological past of Mars. curiosity has also finished its initial mission duration of two years, and achieved its main goal of finding out of Mars could have once supported microbiological life. Yes, it could have. Driving to Mount Sharp has been delayed significantly in the first year due to interesting scientific discoveries close to the landing site, and has been delayed slightly in the second year due to being forced to avoid fields of sharp rocks on the ground similar to those that damaged the aluminum wheels of curiosity earlier in the mission. (b.r.)

esa–d. dUcros, 2014

cUriosiTy 2 years on mars

t

he fifth and final AtV, named after the belgian scientist who formulated the big bang theory, Georges Lemaître, has been launched on the night of 29th July from Kourou, French Guiana. AtV-5 was launched successfully and opened up its solar panels at an altitude of 260km. AtV-5 completed its planned docking to the International Space Station August 12. the vehicle delivers 6602kg of cargo, breaking the record for heaviest spacecraft launched in the Ariane program. the largest experiment carried up is eSA’s electromagnetic Levitator, which will study weightless suspended metals as they are heated to melting and cooled, a process that may advance industrial casting processes. AtV technology will not be wasted; it will be reused in NASA’s Orion program in 2017. (b.r. ) eSA

NASA

eXomars may face deLay

roseTTa arrives aT comeT

August 5, 2014

esa/roseTTa/mPs for osiris Team mPs/UPd/Lam/iaa/ sso/inTa/UPm/dasP/ida

THaLes aLenia sPace-iTaLy

August 6, 2014

t

he rosetta spacecraft has arrived at comet 67P/churyumov-Gerasimenko after a ten-year journey, and is currently in orbit around the comet. rosetta has started its series of complicated burn pattern, which brings it through triangle-shaped orbits into a stable orbit around the comet.

During this time, rosetta has taken several pictures from a wide variety of angles of comet. rosetta will follow the comet as it reduces its distance to the sun, as the changing temperature will cause the surface to change and a tail to develop.

A 100kg lander is planned to be deployed in November to measure the surface changes from as close as possible for as long as the lander survives. (b.r.) eSA, NASA

06

t

he launch of Mars rover exoMars, currently planned for 2018, may face a further delay to 2020 because of funding issues and engineering problems. the project started back in 2002 by eSA with the help of NASA. NASA however, pulled out in 2011 because it could no longer fund its participation. russian Space Agency, roscosmos bailed eSA out and took over part of the development. A radical change in design caused further delays to a 2018 launch. A preliminary design review planned for July 2014 was postponed to mid-September due to delays, although eSA is still trying hard to reach the 2018 launch window. A delay to 2020 would come with two years of extra costs, amplifying the funding issues further. (b.r.)

Nature

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Current Affairs

I

ndia’s directorate general of civil aviation has suspended two Jet Airways pilots over an incident regarding an uncontrolled descent while in Turkish airspace on August 8, 2014. Indian media reported that the aircraft was operating between Mumbai and Brussels when it unexpectedly descended from 34,000ft to 29,000ft. This caused the Ankara air traffic control to issue an emergency message inquiring on the change from the assigned flight level. At the time of the incident, the pilot-in-command was reportedly on a so-called controlled rest, while the co-pilot claimed to be working on an electronic flight bag. Immediately after the message from Ankara ATC, the captain was woken up to raise the aircraft to a newly designated flight level of 32,000ft. (J.L.) Flight Global

Airbus A330neo

14-06-2014, Farnborough, UK Airbus Group

08-08-2014, Ankara, Turkey

Airliners.be

Uncontrolled Descent

A

irbus aims to complete the transition to complete A330neo production by the end of 2019, following its launch of the re-engined type. Airbus is intending to introduce the initial variant, the A330-900neo, before the end of 2017 and roll its output over to the new type exclusively during 2018/2019.

Airbus has a backlog of 232 passenger A330s, mostly the larger A330-300, but it is producing the type at a fast rate of 10 per month. Chief operating officer for customers, John Leahy, says a couple of hundred aircraft of the current A330 can be produced before they completely transition to producing the A330neo. But he is confident that the popularity of the type will enable Airbus to bridge the gap to the beginning of A330neo production. He states there are good and solid reasons to buy current A330s today. (J.L.) Flight Global

Turbofan and fake diamonds

12-08-2014, Colombus, Ohio, USA

World’s Largest Sea Plane

E

ngineers at Ohio State University are using zirconium dioxide - the ceramic used to produce synthetic diamonds - to protect jet engines from high-temperature corrosion.

The fan blades in modern aircraft engines are coated with a protective ceramic to keep them from overheating. When particles of sand are sucked in and come in contact with the extremely hot blades, they melt and turn into glass. When it cools, it forms an inelastic layer on top of the protective coating. When the blades heat up again, the glass doesn’t expand and breaks off the ceramic. Zirconia has the ability to force the glass to bond with other elements in the coating. It turns the glass into an additional layer of protective ceramic every time new sand contacts the blades and melts. (J.L.) PopScience

Popscience

Olivier Cleynen

29-07-2014, Zhuhai, China

T

he Chinese aircraft manufacturer, Aviation Industry Corporation of China (AVIC), started a trial production of the TA-600 amphibious aircraft. With an expected first flight late next year, the Chinese plane would replace Japan’s ShinMaywa US-2 short takeoff and landing aircraft as the largest amphibious aircraft. Larger than a Boeing 737 aircraft, the TA-600 aircraft has a maximum takeoff weight of 53.5ton and a maximum range of over 5,000km. In terms of design, the TA-600 is based off another Chinese design, the 45ton Harbin SH-5. In historical comparison, the eight-engined Hughes H-4 “Spruce Goose”, the largest seaplane ever built, weighed 180 tons in full and had a wingspan of 97m. (J.L.) Aerospace Technology

October 2014 Leonardo Times

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copyright

Predictive RANS Uncertainty Quantification of Turbulent Flow Simulations

The workhorse tool for computing turbulent flow fields in industry are the ReynoldsAveraged Navier-Stokes (RANS) equations. Although computationally tractable, they are subject to multiple sources of uncertainty that corrupt their predictions. The effect of these uncertainties on the model output should therefore be quantified in order to assess if a RANS prediction is actually trustworthy.

TEXT Wouter Edeling, PhD student at Department of Aerodynamics, TU Delft & Laboratoire Dynfluid, Ecole Nationale SupĂŠrieure des Arts et MĂŠtiers

B

efore the introduction of the modern computer, the two fundamental pillars of science were theory and observation.

Although the latter directly measures some (physical) Quantity of Interest (QoI), it is not free from error as imperfect instruments corrupt the observations to a certain degree. A theory in science is described by a mathematical model, which is an abstraction of some physical reality. Unfortunately, these too are subject to uncertainty. Most models have a collection of parameters, which must be tuned in order to, fit a set of reference data. Model performance may strongly depend on the obtained parameter values, and they may well change when the model is applied to a different scenario. Besides imperfect knowledge about the optimal parameter values, errors are also introduced due to the model structure itself. Often, the physical processes which govern reality are not perfectly understood, and assumptions have to be made in the mathematical form of the model. This error, denoted as model inadequacy in the following, is a major source of error that remains difficult to estimate.

Due to the rapid increase of computing power over the past few decades, compu-

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tational models (discretized mathematical models) became the third indispensable pillar of science. All three pillars and their associated errors are depicted schematically in Figure 1, but the focus of this text is on computational models. These models allow for the simulation of physical processes of great complexity, an example of which are turbulent flow fields. In order to compute turbulent flows, the workhorse tool of industry are the Reynolds-Averaged Navier-Stokes (RANS) equations. Here, only the averaged flow is resolved numerically, and the effect of the turbulent fluctuations on this mean is modeled by means of an embedded turbulence model. These models are no exception in that they are also affected by all previously mentioned sources of uncertainty. They possess a set of empirically determined closure coefficients, whose best-fit values are unknown a-priori. Furthermore, since the main tool used in their derivation is dimensional analysis rather than physical insight, they too are subject to model inadequacy.

Nevertheless, for high Reynolds number flows of engineering interest, the RANS turbulence models remain the only computationally tractable option to make predic-

tions for an unobserved QoI. We stress the word unobserved here, since in a prediction scenario typically no experimental data will be available. Thus, given the fact that predictions are made using turbulence models, it is important that the uncertainty in the model output is quantified such that the credibility of a prediction can be assessed. The fundamental question therefore is: How can reliable predictions, with quantified uncertainty, be made using RANS turbulence models when no experimental data is available in the predictive phase?

Bayesian statistics To answer this question, a Bayesian approach to Uncertainty Quantification (UQ) can be used, which unifies the computational model, experimental data, plus all their sources of uncertainty into a single statistical framework. In a Bayesian setting, uncertainty is represented by probability, through the use of probability density functions (pdfs). In this case, a pdf of a closure coefficient represents the lack of knowledge in that coefficient. The central theorem is Bayes’ theorem, which in its unnormalized form is given by

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(1) Here, θ is the vector of uncertain closure coefficients belonging to a chosen turbulence model, z is a vector of experimental data and dp is a probability density function (pdf).

Within the bayesian framework, it is allowed to start with a belief. In equation (1), this belief is represented by the so-called prior distribution p(θ). In this case, it represents a belief that was held about the possible values of the closure coefficients, before any data became available. the other term on the right-hand side is called the likelihood function, i.e. the probability of observing the data, given a set of values for θ. It measures the compatibility of the data with a given hypothesis. the computational model enters equation (1) via the likelihood function, since the model output must be compared to the data in order to compute the value of p(z|θ). Finally, the term p(θ|z) is called the posterior density of θ, which is the probability of θ after the data is observed. thus, it can be viewed as an updated belief based on the available experimental data. When at a later time more data becomes available, the posterior can be used as a prior in the next bayesian update.

Bayesian caLiBraTion essentially, (1) is a statistical calibration. So, what happens when it is used to calibrate the closure coefficients of for instance the baldwin-Lomax turbulence model? consider the problem of multiple turbulent boundary layers, each one subject to a different stream-wise pressure gradient.

For each pressure gradient, experimental velocity data is collected and an independent bayesian calibration is performed. the

W.n. eDeLing

TinsLey oDin eT. aL.

coPyrighT

Figure 1. the imperfect paths to knowledge (Oden, 2010).

Figure 2. the posterior distribution for the closure coefficient κ. each distribution was calibrated under a different pressure gradient, ranging from favourable to strongly adverse

resulting marginal posterior distributions of the closure coefficient κ are shown in Figure 2. clearly, there is a large degree of variability in the posterior pdfs. these results challenge the traditional approach, where only one deterministic calibration is performed, after which universality is assumed regardless of flow topology. In other words, κ is often fixed to 0.41, whether the baldwin Lomax model is applied to just a boundary layer or to the turbulent flow over an entire aircraft wing. In light of the results of Figure 2, this is unlikely to be the most optimal choice, and more importantly, it shows that it is very hard to make an optimal choice a-priori.

However, as shown it is possible to calibrate using (1), after which the mean model output will fit the data nicely. Moreover, the posterior output variance is a measure for the uncertainty due to imperfectly known closure coefficients.

While calibration is necessary, is it not sufficient for predictive flow simulations as it only ensures that the turbulence model can predict observed quantities in observed scenarios. Furthermore, although now a measure for the parametric uncertainty is available, the uncertainty due to model inadequacy remains unquantified.

PreDicTion UnDer UncerTainTy to tackle these two issues a so-called bayesian Model-Scenario Averaging can be applied (edeling, 2014). Here, an “averaged turbulence model” for an unobserved QoI Δ is created through a weighted sum over M turbulence models and S flow scenarios. the resulting predictive pdf for Δ is given by

(2) the term p(Δ|Mi,Sk,z) is the predictive pdf obtained by propagating calibrated samples of the posterior distribution (1) from just model Mi and scenario Sk through the predictive model for Δ. the term p(Mi,|Sk,z) serves as a model weight and is referred to as the posterior model probability. It can be considered as a measure of consistency that model Mi had with the calibration data z. It is determined from this data in a separate bayesian inference procedure. Finally, the term p(Sk) weighs the different Sk. A prediction for Δ can be obtained by computing the mean of (2), and a measure for the uncertainty in that prediction is represented by its variance. this measure can be decomposed into contributions due to parametric uncertainty, model inadequacy and the parametric variability observed in Figure 2. As an example, consider the predictive boundary layer flow in Figure 3. the mean of (2) fits the validation data quite well. It is important to note that this validation data was not used to create the prediction, it’s only plotted for reference.

Finally, notice that the uncertainty is also quantified, as depicted in the breakdown of √(Var[Δ|z]) in Figure 3.

chaLLenges As bMSA requires samples from the rANS code, it can become very costly for complex flow problems. In this case, it will be necessary to replace the code with a surrogate model, which mimics the full simulation code while being cheaper to evaluate. this is currently an active area of research, in part performed by MSc students.

Wouter edeling, W.N.edeling@tudelft.nl

coPyrighT

references

Figure 3. A prediction with quantified uncertainty (left), and the decomposition of the uncertainty into different sources (right).

[1] Oden, t. and Moser, r. and Ghattas, O., “computer Predictions with Quantified Uncertainty”, IceS-rePOrt 10-39, the institute for computational engineering and Sciences, the University of texas at Austin, 2010 [2] edeling, W.N. and cinnella, P. and Dwight, r.P., “Predictive rANS Simulations via bayesian Model-Scenatio Averaging”, (submitted), 2014

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Max Dereta/ Christoph Grete

The Economic Potential of Kite Power

Optimization, Scaling and Economics of Pumping Kite Power Systems

The fundamental working principle of kite power generation is straightforward: a fast-flying kite pulls a tether from a drum, which drives a generator. At the maximum reel-out length, the kite is de-powered and pulled back, to initiate a new pumping cycle. The objective of this innovative technology is to make electricity generation affordable, reliable and clean. The frequently asked question is “How much does it cost?”

TEXT Christoph Grete, MSc graduate Aerospace Engineering

Despite continuous improvements in the field of energy efficiency, global power generation is expected to almost double by 2040 (EIA, 2013). Although the lion’s share will still be based on fossil fuels, generation from renewable energy sources will increase both in absolute and relative numbers. The highest annual growth rates are assumed to be wind and solar power, at 4.7% and 7.1% respectively (EIA, 2013). However, researchers and scientists are in search of a “black swan” for the energy sector.

One candidate is the field of Airborne Wind Energy (AWE). Significant material savings in combination with stronger and more persistent winds at higher altitudes are two major reasons why people see the potential for low-cost energy (Archer, C. L., Delle Monache, L., & Rife, D. L., 2014). It is not only the technical feasibility that plays an important role for successful implementation, but also the economic feasibil-

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ity. In the context of the energy landscape and more specifically power generation, the single-most important parameter is the Leveled Cost of Electricity (LCOE). In other words: how much does it cost to produce electricity over a system’s lifetime?

Research at TU Delft From the various existing AWE concepts, the Kite Power research group at TU Delft focuses on a so-called pumping kite power system (KPS). It uses an inflated wing equipped with a remote-controlled cable robot, the kite control unit, which connects kite and ground station via a tether.

All system components are depicted in Figure 1. The drum-generator unit converts the mechanical traction power into electrical power. One pumping cycle is divided into a traction and re-traction phase. The ability to de-power the kite, while reeling-in, makes it possible to generate net energy over a full cycle.

With its maiden flight in January 2010, the 20kW technology demonstrator successfully proved the working principle.

Successive improvements lead to the key milestone of automatic operation in June 2012. Eventually the goal is to scale a KPS to reach sizes of more than 500kW electrical output, suitable for electricity production at utility scale. To this end, the research objective of the graduation project was defined around the aspect of scaling and economics of a KPS. What is more, optimization problems were defined in order to both operate the system at optimal settings and design the components in the most beneficial way, meaning the lowest LCOE. Methodology Since current AWE prototypes are well below 100kW power output, a physical reference system did not exist. Scaling had to be done on the basis of analytical frameworks, empirical data and numerical

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VaN DeR VLUgT, pescheL, & schMehL, 2013

VaN DeR VLUgT, pescheL, & schMehL, 2013

Max DeReTa/ chRisToph gReTe

Figure 1. System components of the 20kW technology demonstrator of the Kite Power research group at tU Delft.

60 50

200000

Elevation angle β [°]

Average cycle power [W]

250000

40 150000

30 100000

20 50000

S=150.0 m2 , Pnom =350.0 kW; Elec. power [W]

10

S=150.0 m2 , Pnom =350.0 kW; Mech. power [W]

0

Elevation angle β [°]

4

6

8

10 12 14 Wind speed at 10 m height [m/s]

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18

0

Figure 2. Mechanical and electrical power curve of a utility-scale kite power system

simulations. For all system components such as kite, tether and ground station, separate scaling laws were defined for both the physical parameters as well as the respective cost functions. the optimization problem regarding the operation of the KPS was defined for five operational parameters, which were found suitable for the purpose of estimating the power output of the system. these are the minimum and maximum tether length, the set values for the tether force for the reel-in and reel-out phases as well as the tether elevation angle during the traction phase.

For each wind speed, a separate optimization had to be carried out.

Apart from the optimization of operational parameters, the research goal was to identify the ideal system configuration. For this purpose, various component combinations were compared with each other by way of comparing the LcOe for a given location and the (annual) wind data was approximated using Weibull distributions. Systems were compared for kites with sizes ranging from 20m2 to 400m2 and generator sizes ranging from 30kW to 500kW. the fact that the optimization of operational parameters and the optimization of the system configuration are coupled requires a computationally expensive approach. In the developed model, a nested approach is used, meaning that the optimization problem for the system con-

figuration is wrapped around the optimization of operational parameters, which have to be found separately for each configuration and range of wind speeds. appLicaTioN aND ResULTs the developed computational model was applied for two cases: small-scale systems for the deployment in remote off-grid locations and utility-scale units for the european market. considering the former, the optimum system design was found to be a 30kW unit in combination with a 21m2 kite, which results in a LcOe of approximately 250€/MWh. Due to high prices of electricity in off-grid situations this figure is cost competitive against existing solutions such as diesel generators. However, major non-technical barriers were identified, which need to be taken into account when formulating a business case of kite power implementation in remote areas that are often located in developing countries. One of which is the aspect of financing renewable energy technologies, which generally require high initial investments.

Secondly, a large-scale unit was analyzed consisting of a 350kW generator using a 208m2 kite. In Figure 2, the power curve of such a system is shown. Similarly to a conventional wind turbine, the x-axis depicts the wind speed at ground level, in this case 10m height. One can observe that the losses of the system increase for increasing wind speeds. For more informa-

tion on the aspect of power conversion of kite power systems, one is referred to the literature; in October 2013, the first comprehensive textbook with 36 contributed chapters on the emerging Airborne Wind energy sector was published (Ahrens, U., Diehl, M., Schmehl, r., 2013).

In comparison with the small-scale system the LcOe decreases to 60-80€/MWh. It must be mentioned that these numbers assume a system that is built in three to four years time. Due to advancements in the fields of material research (mainly kite and tether) alongside with design improvements of components and optimized system operation, these figures are expected to decrease further. coNcLUsioNs based on the outcome of the simulation results using the developed model, the LcOe of a KPS in the near future is competitive in both analyzed cases of off-grid and utility-scale situations. Further efforts preceding a commercial implementation of the technology on the european market include the successful demonstration of long-term operation and a fully automated launch and retrieval system.

What is more, critical assumptions made in the model, e.g. keeping the aerodynamic properties constant while scaling up, need to be verified and validated using measurement data from test flights in the future.

The RoaD aheaD Starting in the summer of 2014, a joint project in collaboration with the University of Applied Sciences Karlsruhe will set out with the goal of achieving 24 hours continuous flight-operation within one year. For more information one can best follow the news feed of the research group (www.kitepower.eu). christoph.grete@gmail.com references [1] eIA. (2013), International energy Outlook 2013, (U.S. energy Information Administration - DOe/eIA-0484(2013)) [2] Archer, c. L., Delle Monache, L., & rife, D. L. (2014). Airborne wind energy: Optimal locations and variability. renewable energy, 64, 180–186. doi:10.1016/j.renene.2013.10.044 [3] Ahrens, U., Diehl, M., Schmehl, r. (eds.) (2013), Airborne Wind energy, Springer [4] Van der Vlugt, r., Peschel, J., & Schmehl, r. (2013), Airborne wind energy. In U. Ahrens, M. Diehl, & r. Schmehl (eds.), (chap. Design and experimental characterization of a Pumping Kite Power System), Springer

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NASA

DELFI-N3XT mission Launch and operations of the DELFI-N3XT satellite Delfi-n3Xt is a satellite developed by TU Delft, which has been successfully launched on November 21, 2013 with a Dnepr launch vehicle. The satellite has been developed by students and staff from the Faculty of Aerospace Engineering, Delft along with co-operation from students of other faculties, interns from universities of applied sciences & project partners from the Dutch space industry.

TEXT Jasper Bouwmeester, M.Sc. Space Systems Engineering, Project manager Delfi-N3XT

The Mission Delfi-n3Xt is a successor to the successful Delfi-C3 satellite, which has been launched in 2008 and is still operational after six years. It is a part of the Delfi Program; a development line of CubeSats for education, technology demonstration and CubeSat bus platform advancement. A CubeSat is an internationally standardized form factor of one or more blocks of 10cm x 10cm x 10cm. Delfi-n3Xt is a triple-unit CubeSat with a mass of 2.8kg.

A primary educational goal was to train at least sixty students from various disciplines on a real space mission as part of their thesis or internship. With more than 80 students involved in total, this objective has been successfully achieved. Many of our own master students have graduated on Delfi-n3Xt and have started their professional careers in the space sector.

The technology demonstration objective allows the Dutch space sector to test and demonstrate their new space technologies in orbit in a fast and cost effective manner. Delfi-n3Xt demonstrates the functioning and performance of a cold gas micropropulsion system from TNO, a CubeSat transceiver from ISIS and amorphous silicon solar cells from Dimes.

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The major advancements of Delfi-n3Xt on the bus platform compared to its predecessor Delfi-C3 are an agile Electrical Power Subsystem developed in cooperation with SystematIC BV, a more robust Command and Data Handling Subsystem and an active Attitude Determination and Control Subsystem.

The Launch Day On November 21, 2013, many students, staff and press gathered early at the Aerospace Engineering canteen to witness the coverage of the launch and first operations. Because the launch site in Russia is a military base, there was unfortunately no live video feed available. However, we had a program, which is also used at launch control, which showed an animation of the launch and all technical data of the trajectory and stages. Through telephone, we heard confirmation of all phases from the launch site. While being live on several Dutch television channels and radio stations, everyone heard and witnessed the launch starting at 8:10 AM local time.

The relief in the canteen was great when the orbit injection of Delfi-n3Xt was confirmed at 8:26 AM. Immediately, a part of the team moved to a meeting room, which was temporarily setup as Mission

Control Center and another part to the ground station at the EEMCS building.

Already at 9:38 AM, the first pass would be over the Netherlands and according to the operational schedule this would also be about the first time the satellite could be heard. And indeed the satellite was received in the first pass! This was rather extraordinary in technical sense, given the many uncertainties at that time like the exact orbit details and whether the satellite had already finished the first on-board operations including deployment of the solar panels and antennae autonomously. It was also great in terms of PR as the press was still around to cover this exciting moment as well. While the media slowly left the faculty, the analysts and operators concentrated on their important tasks to check the health of the satellite and take action if needed. Luckily, everything seemed fine and later that day, when there were no satellite passes, there was also some time to celebrate this nice event with everyone involved. In the weeks and months thereafter, experiments have been planned and executed and telemetry has been analyzed to obtain preliminary results.

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04-Dec-14 21:46:32

Tu DeLFT

nasa

Figure 1. Mission Control Center during Launch

The T3-ΜPs MicRoPRoPuLsion sysTeM the t3µPS is a micro propulsion system, which is developed by tNO in cooperation with tU Delft, University of twente and SystematIC design bV. eight Cold Gas Generators (CGGs) store nitrogen in a solidified grain. Upon temporary heating one of the grains inside a CGG, the nitrogen is released as gas and enters a tank volume in which it becomes pressurized. by opening and closing a valve, continuously or intermittently, the gas exits the micro-machined nozzle and delivers a thrust of up to 6mN. Shortly after the launch of Delfi-n3Xt, experiments have been performed with the t3µPS by telecommand. In the first phase until the ignition and decomposition of the first CGG the pressure sensor, the temperature sensor and the operation of the valve were tested and shown to be operating within specifications. the plenum was launched with approximately 1bar of pressure inside and this was released till 711mbar with the first actuation of the valve. On November 26, 2013 the first cool gas generator was successfully ignited and decomposed producing gas. After this event, many thrust events have been performed producing relatively small and large impulse bits. A second CGG was ignited and the leak tightness of the tank has been proven to be well within specification. Unfortunately, the operators have not been able to ignite the third and subsequent CGGs due to a fault in the electrical circuit of the igniter. Although this was a disappointment for all involved, it also marks the importance and opportunity which is offered with this relatively cheap

in-orbit technology demonstration: at this moment in time, tNO and its partners have improved the electronics such that they can implement this in other satellites with sufficient confidence including larger and more expensive missions. the majority of the demonstration goals have been achieved for this micro propulsion system.

The isis TRansceiVeRs Delfi-n3Xt is equipped with two redundant CubeSat radios with a VHF downlink and UHF uplink: the Primary transceiver (PtrX) and the Innovative transceiver (ItrX). both systems are developed by Innovative Solutions in Space (ISIS) b.V. the ItrX is also equipped with a ‘click-in’ linear transponder module, which is developed in cooperation between ISIS, tU Delft and the University of twente. the objective of the ItrX is to test and demonstrate a new CubeSat radio from ISIS as successor to their trXUV commercially available radio.

In the first month of operations, the ItrX was in full transceiver mode and the PtrX in receive-only mode during the sunlit part of the orbits. In eclipse, both radios operated in receive only mode to save power. the downlink of the ItrX has been very stable and packets have been decoded at each pass over the Delft ground station from about 5 degrees elevation onwards, using a 18db gain circularly polarized Yagi antenna on ground. During all operations so far, the ItrX has been able to receive and decode telecommmands on its uplink from very low elevation levels.

After the first month, the PtrX was used as main transmitter as this radio has more

output power available and was therefore picked up at the horizon in Delft and by more radio amateur ground stations around the world for enhanced telemetry collection. Also, the telecommanding capability of this radio has been successfully demonstrated many times as well. the downlink frequency has been determined to have only a small offset in the order of a few kHz. this is well within the margins of the assigned frequency bands.

In the first three months of operations, 46701 unique telemetry frames have been received, decoded and sent to the telemetry server. each frame is built up from two sequentially transmitted AX.25 packets with 1792bit of real content each. these packets are sent each second and represent the data measured at the satellite at a 0.5Hz synchronized cycle. this means that about 26 hours of onboard measurements has been received at the telemetry server so far. telecommanding of the satellites have been successful during all times, also while the satellite was transmitting, proving that the radios are full duplex. It can be concluded that both the ItrX and PtrX have performed their main functions well and have been demonstrated successfully.

After the main mission goals had been achieved after three months of operations, a transponder test has been executed for the first time. the transponder beacon has been received during the test, but since this test the operations team has experienced loss of signal of the satellite for which the real cause is yet unknown and recovery attempts are still being made.

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Tno Tu DeLFT/DiMes

isc KosMoTRas

Figure 4. Micro Propulsion System

Tu DeLFT

isis

Figure 3. Amorphous Solar Cell experiment

Figure 2. Launch of Dnepr rocket carrying DeLFI-N3Xt

soLaR ceLL eXPeRiMenT Currently, for most space applications triple-junction solar cells based on GalliumArsenide are used. Cells based on these materials have shown good performance and reliability, but they are expensive, complex to put on thin films and they degrade due to radiation over time. For the solar-cell experiment on the Delfi n3Xt satellite, a payload has been developed in Dimes, the Microelectronics Institute of Delft University of technology. For this payload, fourteen solar cells based on hydrogenated amorphous Silicon (a-Si:H) have been monitored during the mission by measuring the current-voltage characteristics under illumination, and the temperature of the solar cell assembly. the a-Si:H solar cells that are tested in this experiment have a higher radiation tolerance, better annealing properties, and higher power-versus-weight ratio when no cover glass is used. the current analysis shows that the cells have stabilized at about 8% eďŹƒciency, which is in line with the expectations. cuBesaT Bus aDVanceMenTs Delfi-n3Xt has harvested about 11W of power on average during the sunlit part of the orbit. this is about three times as much as its predecessor Delfi-C3. Also, Delfi-n3Xt has proven eclipse operation with the use of a battery. Although the use of a battery may sound trivial, implementing this in a fail-safe manner as done in Delfi-n3Xt is rather complicated and one of the reasons why its predecessor did not have batteries onboard.

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Figure 5. the attitude determination and control system board

In total six sun sensors, four magnetorquers and three reaction wheels developed at tU Delft have been tested and it is proven that all components worked in orbit. Unfortunately, some flaws in the onboard attitude algorithms have been detected and therefore the full potential of the active attitude control is not demonstrated yet. the lessons learned will be implemented in the next mission. the internal I2C data bus stability on Delfi-C3 was a severe (but not mission critical) issue due to a high amount of bit errors and bus lock-ups, which reduced the potential data, yield and complicated telemetry analysis. On Delfi-n3Xt the I2C bus is orders of magnitude more stable. the thermal environment onboard Delfi-n3Xt has been characterized with more than thirty temperature sensors. It is proven that the real results are well aligned with the simulated predictions and also the innovative passive thermal control generated a very mild temperature range for all subsystems inside the main body of about -5°C to 35°C. concLusions anD FuTuRe ouTLooK tU Delft has again proven that one can successfully combine exciting education, technology demonstration for professional organizations and evolutionary advancements of the bus capabilities with the development of a CubeSat. Most of the systems have performed according to their specification, but not all systems and operations have performed flawlessly.

Figure 6. experimental radio transceiver

this is to be expected with a highly ambitious mission with many novel technologies as part of an educational and technology demonstration mission. the team has successfully established failure mechanisms and propagation barriers, reduced interdependencies of subsystems and implemented a smart operations plan which, all combined, has secured the mission despite of the many innovations and the extensive use of non-space grade components. And that with a team, which is relatively inexperienced and still several magnitudes of orders smaller than for the larger satellite missions. Delfi-n3Xt is a mission success!

Currently, a new team of students and staff is working on the DelFFi Mission. this mission is part of the eU funded Qb50 mission in which about 50 CubeSats will demonstrate many new technologies and characterize many properties of the thermosphere (the atmosphere between about 200km and 300km). For the DelFFi mission tU Delft will develop two tripleunit CubeSats that will demonstrate formation flying with the use of a custom developed propulsion system and algorithms. the Qb50 mission is scheduled for launch in 2016 and there are still many opportunities for staff and students to get involved in this mission!

For more information, follow the Delfi program at www.delfispace.nl.

Leonardo Times OCtOber 2014

04-Dec-14 21:46:49

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Team Adrestia

Adrestia’s manned fly-by mission to Mars The first manned mission to the Red planet.

The team that was formed for a Design Synthesis Exercise placed itself as a finalist in the top ten of an International space engineering competition. Team Adrestia, consisting of nine Aerospace Engineering students, competed in the Mars Society’s Inspiration Mars student competition. The goal was to design a manned mission to Mars, which is as safe, simple and cost-efficient as possible. From the 56 Universities and 38 teams competing, this team represents the Netherlands in this race to Mars.

TEXT Shahrzad Hosseini, External Affairs – Team Adrestia

The world’s first space tourist, Dennis Tito, believes that flying a manned spacecraft to Mars could result in the spark for the space industry and become a catalyst for growth, education, knowledge and global leadership around the world. Tito, a U.S. Aerospace engineer and multimillionaire, believes that the mission will not only be an inspiration to the people but also a success for mankind. For this reason, he set up the Inspiration Mars foundation to fulfill this dream.

This dream, of flying mankind to Mars, is a vision which is developing gradually and inspires to set the first footprint on the Red Planet. It is the responsibility of today’s engineers, to make sure this occurs in a safe and sustainable way. With this motivation, Adrestia’s design focuses on an end-to-end fly-by mission launched by 2018, while accommodating for two people.

The Mars Society convention During the 17th Annual International Mars

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Society Convention which was held August 7-9 of this year, all finalists were invited to present their design at the convention. A jury, consisting of members from the Mars Society, Inspiration Mars and NASA, judged each team’s design. The teams’ origins were from all around the world, varying from the U.S.A., Germany, Japan, Russia, India and Poland.

Design process With the fact that only off-the-shelf components could be considered for the design, the team started off the design early November 2013. The design process was initiated by the determination of optional trajectories and preliminary sub-system designs. After this phase, design options were analyzed and critical design choices led to the overall mission overview. Subsequently, the detailed design process began in which all mission specifications were thoroughly identified from launch through landing. In January of 2014, the team finalized the design and an optimization process of two months led to the

final design. This resulted in a spacecraft with a total mass of 15,580 kg performing an optimized Earth-Departure Free-Return trajectory, with a total mission cost of $5.85B. After this, the team was glad to receive its Finalist Certificate from the Mars Society’s president, Dr. Robert Zubrin.

The 38 teams all differed in their approach, design and organization of the mission. Team Adrestia has weighted different mission lay-out against each other, which all led to different design scenarios and operational options.

Mission lay-out The first step of the mission is the launch of a Falcon Heavy which will carry fuel to a Low Earth parking orbit. The second step is the launch of the SpaceX Dragon re-entry capsule with two extended trunks, which carry the crew and the living module on board of a SpaceX Falcon Heavy launcher. Next, on-orbit docking is performed and the refueling process, assisted by the crew with an Extravehicular

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aLeXanDer heLMer, haaLBeeLD FoTograFie

Figure 1. team Adrestia

Activity, takes place. thereafter, the system undocks and the spacecraft is ready to start its interplanetary journey, initiated by a trans Mars trajectory injection. one Man, one WoMan Having a crew of two on-board the spacecraft, special care was needed in order to come up with a Life Support System. Since this mission marks the very first manned deep-space mission, no existing environmental control and Life Support System is readily available under the term offthe-shelf. It was up to the team to find a system which does not only ensure the safety of the crew and sustain human life and workability, but also fits within the demanding limits of the design. the weight- and power budget have been of great importance for all sub-systems. scienTiFic Deep-space eXperiMenTs Inspiration Mars is the first mission to obtain results from human scientific experiments performed in deep space. both physiological and the psychological effects on the crew are tested and results from pre-, and post-mission are later compared. Partly inspired by the Mars 500 project, this mission aims for a number of scientific experiments. these are divided in human experiments, to test and measure phenomena on the human body, and experiments which are directly related to Mars.

the human body experiences quite a change, when situated in deep space for nearly one and a half years. Scientific test and data can quantify these changes in a quite detailed manner. the relation between psychology and cardiac functioning is studied, by tracking the cardiac regulations, blood pressure and monitoring sleep alterations. the degradation of bones and muscles is studied, similar to the ISS, but this mission will contribute to science by releasing the first test results on this topic measured in deep space.

Furthermore the effect of blue-enhanced light is studied, focusing on the crew’s performance as a function of module lighting. Another very important aspect to take into account is the cognitive and emotional adaptation of the crew, and the effect of stress on immunity. Obtaining data for the aforementioned tests, this mission aims to quantify and clarify the effects of long-duration deep space missions on the human body.

FLying By Mars Halfway the 500-day mission, the first manned Martian fly-by is performed with duration of ten hours, approaching Mars to an altitude of 180km. A probe is deployed on the planet to record numerous characteristics of the planet, and images are taken during the fly-by. Using Mars’ gravity, the spacecraft obtains a velocity boost to continue its trajectory and journey back to earth.

BacK hoMe saFeLy In the final stage, the spacecraft approaches earth and the crew moves back to the Dragon capsule with an extravehicular Activity. the living module will continue on its trajectory into a heliocentric orbit where it will be used to collect deep space environment measurements. the re-entry capsule is jettisoned and performs a direct re-entry. Finally, the crew is retrieved from the capsule and this inspirational and innovative mission is completed successfully.

The TeaM’s FuTure Having presented the mission design at the International convention of the Mars Society, team Adrestia ended up in the ranking after four American teams and one German team. this event was not the last one to come. In September the team is presenting the design at Dutch Space, followed later by presentations at the Nederlandse Vereniging voor ruimtevaart (NVr) / Netherlands Space Society and the european Space Agency. For more information on the team and the Mars mission design, www.facebook.com/teamAdrestia can be addressed. references [1] Verschoor et al., “Final report – Inspiration Mars”, January 28th 2014 [2] Verschoor et al. , “Adrestia – Manned Mission to Mars”, March 14th 2014

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Internship report

Internship Universidad de Concepcion, Chile

Last year, three Aerospace students headed out to work in Concepcion, Chile. Besides describing the challenging projects, this article will take you to South-America and delve into working environment and living in a completely different culture, and the many adventures we experienced on this exotic continent.

TEXT Vincent Bijsterbosch, MSc Student Control and Operations Rens Douma, MSc Student Aerodynamics and Wind Energy Djim Molenkamp, MSc Student Control and Operations

W

hen we, independently of each other, heard about this internship opportunity, we immediately all got very enthusiastic and we were easily sold.

Universidad de Concepción is one of the three big universities of Chile. The faculty of aerospace engineering is a rather small building with some basic facilities and one central laboratory area where the students are performing the practical assignments and the group work. The project work is mainly focused on the design and construction of small-unmanned aircraft and helicopters, which included the accompanied electronics. Besides that, the faculty contains a small wind tunnel and has a flight simulator, which is used to predict the behavior of the aircraft during tests.

The assignments One of us worked on a plugin for this flight simulator to simulate a parachute assisted landing for a small UAV. This was a quite challenging task because it entailed combining many aspects from the bachelor phase, from objected oriented programming to flight dynamics and aerodynam-

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ics, in a single large plugin that had to not slow down the flight simulator too much.

While this project was more focused on the flight simulator, the other two students were involved in getting the multicopter project off the ground again, with the quadcopters available, the Mikrokopter QuadroKopter and a quadcopter based on the ArduCopter hardware as can be seen in Figure 1. One assignment was to implement ultrasonic sensors using an Arduino microprocessor, which were programmed for the use of an automatic landing system. The second assignment was more focused on the design of new ground station software and making it compatible with the hardware at hand, which was based on a Raspberry Pi. The challenging aspects of the quadcopter projects were the combination of the control theory, interface design and programming learned in the master program combined with the practical touch of working with hardware. The most exciting activities were the numerous drone test flights, which incidentally resulted in crashing into a telephone cable.

Life in Chile Arriving without any notable knowledge of Spanish, the language barrier showed to be quite a challenge to overcome in the first few weeks as well. Even buying small things could be a complicated process, not to speak about dating girls! But when one really has to, learning goes really fast and after one month, our Spanish proficiency was good enough to get around. In hindsight, being completely lost in the beginning was like a charm for us. It was very valuable to experience how fast one can adapt to a completely different culture.

The working ethos and the perception of time are different from the Netherlands, being more slowly paced (tranquilo) and with longer working days. However, it was incredible to see how open, warm and helpful people can be. The Chileans are not very used to foreign people and especially not to tall Dutch guys with blonde hair, so on the street we were objects of large interest. Sometimes while walking on the street we got approached by Chileans who wanted to hang out with us, which was always big fun. We got invited on events like asado’s (barbecues!) all the

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TRaVeLLing ThROUgh sOUThameRiCa being at the opposite side of the world made us realize that we should not let

DiYDROnes

WeeKenD TRiPs Of course, another big reason for choosing chile was the totally different culture, in a continent we had never even been before.

Searching the Internet, it didn’t take long to see that chile has a lot of natural beauty to explore and our professor was very supportive in making it possible to visit as many of these wonders even during our internship period. Luckily, chile has a very good, frequent and affordable bus transportation system, which we used extensively to travel through the country during weekend trips. the great thing about chile is that it practically has all possible climates cramped into one country, which enabled us to see all the kinds of beauty which nature has to offer. Within half an hour we were at beautiful beaches along the Pacific coastline in the west, while going east would lead us to the magnificent Andes Mountains. All in all we visited some beautiful national parks in the area.

On one long weekend we rented a car and drove over a thousand km north of concepcion, past Santiago, to visit Valle de elqui, also known as Pisco Valley. We visited coquimbo and La Serena, two beautiful seaside cities. From here we drove to the highest mountain pass between chile and Argentina at 4800 m, travelled by only 200 cars a year, as can be seen in figure 2! When we returned to La Serena it was time to visit a Pisco factory. Pisco is a typical chilean alcoholic drink made from grapes and of course we couldn´t resist when they offered us to taste some premium piscos. because Valle de elqui is one of the valleys in chile that enjoys the sunniest days in a year, we also tried out some solar cooking, very tasty! Last but surely not the least, we also experienced a 6.8 earthquake, which the chileans don´t even consider an earthquake yet! Other weekend trips included visiting the countryside houses of our friends, going to a huge beer festival in a German settlement in the South and seeing the vivid and lively city of Santiago!

Figure 1. One of the drones that was used for test flights

Rens DOUma

UniVeRsiDaD De COnCePCiOn

time, which is a great opportunity to have fun and build life-long friendships.

Figure 2. Highest Andes Mountains border pass between chile and Argentina

this opportunity pass without travelling through some of the surrounding countries located in this amazing continent.

At the end of our internship, we went to the far-south end of the world: Patagonia, where we did a 4-day trek to see glaciers and fjords while high-fiving some wild penguins. Later we went among others to the Atacama Desert, the driest desert in the world, crossing the border to bolivia and Peru to see the wonders nature has to offer like the Salar de Uyuni and Machu Picchu. Other countries that were visited were Argentina, Uruguay, Paraguay and brazil.

a social/cultural viewpoint. the diverse internship assignments gave us a good practical sense and understanding that is missing in the aerospace curriculum. We were sincerely moved by the warm way in which we got welcomed into the chilean culture. During this intense experience, we made numerous friends, who can be considered our second family, and in the end, this resulted in a big and quite emotional goodbye party. We can recommend everybody to step outside their comfort zone and go on an unforgettable adventure in chile. One thing is for sure, some day we will definitely return to this won-

All in all we considered this internship experience to be extremely valuable, both from an academic viewpoint as well as

derful continent!

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LVD

THE ORIGINS OF AIRPORT SECURITY

METRO GOLDWYN MAYER, VIA EVERETT COLLECTION

130 aircraft hijacked within five years in US

The aircraft hijackers of the late 1960’s can’t be compared to today’s terrorists: rather than seeking to harm western society, they consisted mostly of people rejected by society seeking to build a new life elsewhere. A famous example is the story of Roger Holder, a troubled Vietnam veteran and his girlfriend Cathy Kerkow, who commandeered Western Airlines flight 701 in 1972, wanted to fly it to North Vietnam, hoping to expose the brutality and futility of the Vietnam War. When he asked Cathy to join his plot she reportedly casually responded: “So, what do I wear to a hijacking?” (Garner, 2013) In 2013, author Brendan I. Koerner published the book “The Skies Belong to Us: Love and Terror in the Golden Age of Hijacking” about their fascinating story.

TEXT Tom Pruijsers and Sarah Dutrieux, Members of the aviation department, Students BSc Aerospace Engineering

THE ‘GOLDEN’ AGE OF HIJACKING The ‘golden’ age of hijacking refers to the period between 1968 and 1972 in which aircraft hijackings occurred nearly on a weekly basis, sometimes even twice on the same day (Sulzberger, Weiser, 2009).

In the US alone, over 130 aircraft were hijacked during this time period. To most hijackers, Havana, Cuba was supposed to be a haven where Fidel Castro would welcome them as heroes of the revolution.

To them Cuba was a place of true freedom and democracy where they could start new lives without inequality and injustice.

The reality, however, was quite the opposite. Castro welcomed them in order to frustrate the US and for personal gain, by

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letting the airliners pay ransom to retrieve the aircraft. But he actually despised the hijackers, who were captured by the secret police after they landed and were consequently interrogated for weeks. If the hijacker were lucky, he would be put away in “Casa de Transitos” (which translates to Hijackers House) with sometimes as many as sixty other hijackers. However, if he were not, he would be sent away to tropical gulags where beatings, executions and torture were a common occurrence.

This however did not deter other hijackers, who were hoping they would be the one to get that heroes welcome from Castro (Koerner, 2013), (Mensing, 2010).

So many aircraft were commandeered to

Cuba that many aircraft operating in the southeast of the US were equipped with charts for landing at José Martí airport Havana. Phrase charts with standard Spanish sentences such as “we need to refuel” were also present. Instructions were also written for crew on how to react in case of a hijacking, which included that they should follow every instruction from the hijacker (De Paul, Taillon, 2002), (Koerner, 2013).

THE SEARCH FOR SOLUTIONS Until 1968, there were no real security measures to prevent hijackers from boarding an aircraft, there were no metal detectors, no mandatory luggage searches and you were not even required to show an

Leonardo Times OCTOBER 2014

04-Dec-14 21:49:57

ID. The airlines feared that it would cause too much discomfort for the passengers before boarding and invaded their privacy and they thought these measures would have a larger negative impact on the experience of flying than the hijackings. In addition, intensive security measurements such as metal detectors were deemed too expensive (Gardiner, 2013).

But as the number of incidents kept growing, it was clear that measures that are more effective needed to be taken in order to prevent further hijackings. A commission was created to search for possible solutions for the security problem at airports.

The commission received several suggestions from the general public for increasing safety. One solution would be to lock the cockpit door. This however was not implemented because it was feared that the hijacker would still be able to force the pilots to land in Havana by taking the flight attendants or passengers as hostage. Another suggestion was to arm the crew with (tranquilizer) guns. The plan was rejected however, because the FAA did not want to risk an airborne gunfight. But there were also some more unconventional suggestions like installing trapdoors to drop a hijacker into the luggage compartment when trying to enter the cockpit or making every passenger wear boxing gloves in flight to make sure that they were not able to handle weapons. Another solution was to play the Cuban national anthem at airports and to interrogate anyone that sang along.

The most popular suggestion to the FAA was to build a full replica of José Martí airport somewhere in Florida, where the hijacker would then land and be arrested.

The plan was unfortunately too expensive.

The state department came with the idea of offering free tickets to Havana to people who vowed never to return. Castro however, blocked this solution by not accepting these flights at the airport (Koerner, 2013).

A NEW KIND OF THREAT These new security screenings proved very effective in protecting airliners from hijacking. And in the years leading up to 9/11 only a handful of aircraft were commandeered to Havana, But the system was not improved during the following decades and unfortunately proved to be insufficiently capable of dealing with a different kind of threat, namely hijacking an aircraft as means for mass murder. This became apparent with the Lockerbie aircraft bombing in 1988, but the most significant example is of course the 9/11 attacks on the World Trade Center twin-towers in New York. This attack led to a complete overhaul of airport security. Bulletproof, locked doors were now finally installed on aircraft to prevent the use of an airliner as a weapon of mass destruction and on the ground, the security was immensely tightened. In 2006, after the discovery of a terrorist plot to use liquid bombs on airplanes heading to the US, another wave of security measures was implemented, including the banning of checking in liquids.

PREVENTION IS BETTER THAN CURE With the ever-growing globalization and the constant increase of air traffic, it is important to keep improving the security of airports. New ways of handling secuDESMOND SWAMY

FAA agent John Dailey created the first method that was implemented to increase airport security in 1969. The plan consisted of picking out passengers who showed a certain behavioral pattern, like buying

a one-way ticket, avoiding eye contact or paying in cash. These persons were then taken for individual scanning. The method proved to be effective and during the first three years of the program, several thousands of weapons and other prohibited items such as illegal drugs have been confiscated. Sometimes guns and knives were found thrown away in plants or bins around the airport, discarded by would-be hijackers who were discouraged by the new safety regulations. From interviews with searched passengers, it also became apparent that most passengers did not mind the search procedure at all, and were even glad that measures were taken to improve safety. This then paved the way for the milestone regulation change in 1973, which made metal detector scans for every passenger compulsory (Dailey, 1973).

rity are already being implemented. An example seen in the 2014 FIFA world cup is the Qylatron depicted in Figure 1, produced by Qylur security systems. The device consists of five pods placed around a single scanner, thus being able to scan the bags of multiple people at the same time (Davies, 2014). These kinds of innovations are necessary to increase threat detectability, increase the speed of boarding and prevent invasion of privacy as much as possible. With the continuing unrest in the Middle East and the rise of dangerous new terrorist groups like ISIS, it is important for airport security to constantly evolve and always be one step ahead of possible threats. Let’s not wait for the next attack before implementing new security solutions.

References [1] Garner, D., “Bonnie and Clyde, The Aerial Version ”, New York Times, New York Edition, p. C26, June 14, 2013 [2] Koerner, B.I., “The skies belong to us: Love and Terror in the golden age of hijacking”, Crown, 2013.

[3] Sulzberger, A.G., and Weiser, B., “On Return from Cuba, an Arrest in ’68 Hijacking”, New York Times, New York Edition, p. A19, October 12, 2009 [4] Koerner, B.I., “How Hijackers Commandeered 130 American Airplanes – in 5 years”, http://www.wired.com, June 18, 2013 [5] Mensing, A., “Take This Plane to Havana! U.S. Perceptions of Cuba: The Hijacking Crisis of 1968-1973”, American University, Washington D.C., spring 2010 [6] De Paul, J., and Taillon, B., “Hijacking and Hostages: Government Responses to Terrorism”, Praeger Publishers, p.16, 2002.

[7] Gardiner, B., “Off With Your Shoes: A Brief History of Airport Security”, http:// www.wired.com, June 14, 2013 [8] Dailey, J.T., “Development of a Behavioral Profile for Air Pirates”, 18 Vill.

L. Rev. 1004, 1973 [9] Davies, A., “The Brilliant Machine That Could Finally Fix Airport Security”, http://www.wired.com, July 14, 2014

Aviation Department The Aviation Department of the Society of Aerospace Engineering Students ‘Leonardo da Vinci’ fulfills the needs of aviation enthousiasts by organising activities, like lectures and excursion in the Netherlands and abroad.

Figure 2. All five pods of the Qylatron can be used for luggage scanning at the same time, supposedly increasing the hourly capacity of the security process by five.

OCTOBER 2014 Leonardo Times

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Roscosmos

Interview

Soviet Moon Program Interview with Dr. Malenkov

During the 1960’s, the United States and the Soviet Union were in fierce competition to put the first man on the moon. A lot has been told on the American efforts but the Russian story is not often told in the west. The Leonardo Times spoke to Dr. Malenkov, a prominent engineer on a number of Soviet space missions to share his experiences.

The interview was conducted in Russian.

TEXT Dr. Mikhail Malenkov, Professor at the Polytechnic University of St. Petersburg Jeroen Wink, Student Aerospace Engineering, Editor Leonardo Times TRANSLATION Eugenie Zagrazki

The Beginnings The most important ideas considering the practical realization of the Soviet Moon program, including the idea of operating unmanned rovers on the lunar surface, were incubated in the team headed by Sergei Korolev. In the 1950s, he and his team founded the Experimental Design Bureau N1 (OKB1) in a small suburb of Moscow, which has now been named after Korolev. The Experimental Design Bureau later grew to become the Energia Company, which was, and still is, responsible for the largest part of the Soviet/Russian space program including the ISS. At OKB1, the conquest of the moon started. Before any manned mission would be send, the Moon should be investigated using unmanned spacecraft. The first step was to send an unmanned vehicle on a Lunar impact trajectory. Luna 1 was launched in January 1959, but failed to reach the Moon due to a wrongly timed orbit correction. Despite this setback, the OKB1 continued their effort and launched

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Luna 2 in September of the same year.

The mission succeeded and Luna 2 became the first man made object to reach the Lunar surface. Luna 3 quickly followed the success of Luna 2, which on October 7 sent the first images of the backside of the Moon to the Earth.

As said, this success did not come without hurdles. Apart from the failure of Luna 1, the moon programmed so far had suffered four launch failures, three of which exploded on the launch pad. On the positive side, by overshooting the moon, Luna 1 became the first man made object outside the Earths sphere of influence.

Landing on the moon The next big step in the conquest of the moon was to achieve a soft landing on the lunar surface. This leap took quite some effort, 6 years of development and 13 failed launches. The goal would be met eventually, but sadly, Sergei Korolev would not live to see the positive results

as he died during an unsuccessful operation on an internal bleeding in January 1966. As if he had foreseen his imminent death, Korolev transferred a large part of his research and development to another factory in November 1965. The S.A. Lavochkin factory was instructed to develop an all automatic spacecraft for Lunar research as well as spacecraft for Mars and Venus missions. The Lavochkin factory had a lot of experience in building combat aircraft in WW2. After the war ended, Lavochkin became an important research and development center for the Soviet Space industry and it was this team, under the guidance of Chief Engineer Georgi Babakin, which achieved the next big leap.

On February 3, 1966, the Automatic Lunar Station Luna 9, with a mass of 100 kg, performed a soft landing on the lunar surface.

Luna 9 landed in the Ocean of Storms and in four separate broadcast sessions transferred panoramic views of the Lunar landscape to the earth. The Americans quickly followed when four months later, the American Surveyor 1 achieved the same

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goals.From this point onwards, the Americans had started to catch up. In December 1966, Luna 13 measured the stability of the lunar soil with a specially designed penetrometer, a feat that the Americans quickly followed with the Surveyor 3 mission. by this time, scientist at both sides were analyzing and comparing the results of the surface research to develop landing strategies for the manned mission.

TRacKs on The LUnaR sURFace On August 2, 1971, during the lunar morning, two man made vehicles from earth simultaneously roved on the lunar surface.

After its ninth lunar night spent on the Moon, the first movable automatic lunar laboratory Lunokhod 1 opened its solar panel to start its operations and traversed the lunar surface for its tenth lunar day. At the same time, the first American moon rover, delivered to the Lunar surface by Apollo 15, drove on the Lunar surface with two American astronauts David Scott and James Irwin as its Lunar Module Pilot. this activity was in sharp contrast with the lunar surface’s history as only natural celestial bodies visited the virgin lunar surface.

Due to the absence of an atmosphere, left the moon speckled with craters of different sizes. And now, on the dangerous

m.a. maLenKoV

m.a. maLenKoV

Roscosmos

Figure 1. Dr. Mikhail Malenkov, Lead Mechanical engineer for Lunokhod 1 and 2

Figure 2. Lunokhod 1 Lunar rover

slopes of these craters, the greatest exploration in human history progressed by Lunokhod and the American Lunar roving Vehicle. the two vehicles actually operated quite close to each other as only a few hundred kilometers separated the American and Soviet explorers. the success of Lunokhod 1 was repeated by Lunokhod 2, which still holds the distance record of any rover on an alien surface. the records of the two leading space powers have not been surpassed to date. It is only now, more then 40 years later that the same situation could be repeated. Currently, the number of countries developing missions to the moon has at least doubled. the two Space race participants, in their effort on landing automated vehicles on the Lunar Surface, have been joined by India, China and Japan and to a certain extend by the european Space Agency.

konur Cosmodrome. Surprisingly, the

sPace Race and seTBacKs the development of the Lunokhod also had its fair share of hurdles. the assembly of the Lunokhod with the automated landing station was carried out for the first time already in February 1969. However, its launch was unsuccessful. the Proton-K carrier rocket failed during the flight and the debris of the Lunokhod were found on the Kazakh steppes around the bai-

opinion the best example of the tension

wheels and the landing gear where found undamaged and were returned to the engineers of VNII transmash, where these systems were build later.

After the failed launch of the Lunokhod, due to either the political or scientific reasons (probably both), leaders of the Soviet Lunar Program decided that priority should be given to Lunar sample return. by that time, the USSr already realized that the Americans would be the first to land a man on the Moon. the rocket N1, which was being developed for the Soviet Manned Moon mission, was plagued with failures. the political and scientific leaders figured that we, the Soviets could still be the first to return lunar soil to the earth with the help of automated spacecraft. the events that followed are to my between the American and Soviet space programs.

On July 13, 1969, Luna 15 was launched for the second time from baikonur. this spacecraft, equipped with a landing system, was designed to retrieve samples of the lunar service and launch them back to the earth. three days later, on July 16, OCtOber 2014 Leonardo Times

Interview 1014 (1).indd 23

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lunar night, the lid would close to insulate m.a. maLenKoV

m.a. maLenKoV

the structure. to protect against the cold environment during lunar nighttime, the rovers were equipped with polonium-210 radioisotope heating units. the rovers were remotely operated from the earth and were outfitted with a array of different cameras and radiation sensors. Furthermore, both Lunokhod 1 and Lunokhod 2 were equipped with penetrometers to probe the structural properties of the lunar soil. the two rovers lasted several months on the lunar surface and traversed between Figure 3. Mock up of Automatic Lunar Station Luna 16

Figure 4. Mock up of Automatic Lunar Station Luna 9

them more than 50 km. Apart from providing a large quantity of tV images of the lunar landscape, the Lunokhods provided

Apollo 11 launched from the Kennedy

three days later. the spacecraft success-

Space Center, Cape Canaveral, Florida.

fully retrieved samples of the lunar soil

While the American spacecraft was on

and placed them in a reentry capsule. Pro-

its way to the moon, Luna 15 was already

pelled by a return rocket, the reentry cap-

maneuvering in Selenocentric orbit. the

sule made its way back to earth and re-

landing of Luna 15 was planned for July

entered earths atmosphere on September

20, 1969. However, unanticipated orbital

24, 1970 landing on the Kazakh steppes.

manoeuvres needed to be performed in

the success of Luna 16 was a great land-

order to assure safe landing of the space-

mark in the Soviet space program and

craft. this caused a delay. because of this

resulting in the continuation of the Soviet

delay, the Apollo 11 landed on the moon

of their kind on the lunar surface. After

Lunar program even after having lost the

the end of operations of Lunokhod 2, it

Space race to the Americans. In November

became silent on the lunar surface, with

the same year, Luna 17, delivering Lunok-

no spacecraft landing or roving on the

hod 1 was launched, followed three years

surface of the Moon for many decades.

later by Luna 2.

Luckily, the situation changed. the Chi-

before Luna 15. On the historic day of July 21, the first human in history to walk on the moon, Neil Armstrong, left his traces on the lunar surface while expressing the most famous sentence in the history of space flight; “that is one small step for man and one giant leap for mankind�. On the same day that Armstrong traversed lunar surface, Luna 15 landed on the Moon.

Since the automated vehicle would need very little time to collect its sample, it was still hoped that we could still be the first to bring back a lunar sample to the earth.

measurement data on X-ray radiation, spectrographical analysis of the lunar soil and cosmic background radiation.

Furthermore, they were equipped with reflectors. Currently, these reflectors are still used to determine the exact distance between the earth and the Moon. the Lunokhod program was a great success and remains to date the only spacecraft

nese rover Yutu visited the Moon recently the Lunokhods consisted of a tub-like

and both russia and europe are planning

pressure vessel with a large convex lid

missions to land on the Moon again and

propelled by eight independently pow-

progressing the heritage of the Lunokhod

ered wheels. the rovers had a size of 2.3m

program.

x 2.3m. the inside of the lid was equipped with solar panels, providing power to the rovers during daytime operations. During m.a. maLenKoV

Sadly, the spacecraft entered emergency mode during landing, 2.5 kilometers above the surface, resulting a crash. Since the Apollo 11 mission resulted in a success, the Space race was over.

ReTURn oF LUnaR samPLes Afterwards, the Soviet Union made several attempts for automated lunar sample return. After a number of orbit injection failures, we finally succeeded with Luna 16. On September 12, 1970 Luna 16 was launched. It performed nominally and successfully landed on the Lunar surface

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Figure 5. tracks of Lunokhod 2

Leonardo Times OCtOber 2014

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The sky is no limit!

The Dutch Aviation Group (DAG) is an association consisting of companies and organisations supporting the aviation industry with their knowledge, expertise and experience on complex technical, economic and sustainable aerospace matters.

The main purpose is to provide a network for sharing knowledge and experience, exchange information and enhance the cooperation amongst organisations working within the aviation and aerospace industry.

We achieve these goals through the organisation of conferences, meetings and networking events.

www.dutchaviation.nl

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dag.adv.leonardo.2014.indd 1

04-09-14 09:11

Interview

FUTURE OF THE DUTCH MILITARY AIR CONTROL

Interview with Commandant, AOCS, Nieuw Milligen

The Dutch government recently announced the closedown of the Air Operations Control Station in Nieuw Milligen from 2018. At this military base, the Military Air Traffic, the Air Battle Management and Air Surveillance are controlled. The commander of AOCS, Colonel Henk Ras, was asked about his vision on the new operational system and the future of the Dutch Military Air Control.

TEXT Shahrzad Hosseini, Student Aerospace Engineering, Editor Leonardo Times Sushant Gupta, Student Aerospace Engineering, Editor-in-chief, Leonardo Times

S

tarting in1986 at the Dutch Royal Military Academy, Colonel Ras wanted to become a pilot in the ‘top-gun era’ of that time. In the process of the selections he found that this is not what he will be doing in the future, yet he did want to pursue a career working with fighter jets.

After the four-year military educational program at the Dutch Military Academy, he started working at the Air Control training at AOCS in 1990. “Air traffic management generally leads aircraft from A to B and back, but military air control focuses on missions and tactical actions”, according to the Colonel.

From 1990-2000, he worked at AOCS, after which he left to join the staff at the Royal Netherlands Air Force to broaden his knowledge and profession. Later, he was given the opportunity to join NATO AWACS, and worked there as a Mission Commander and Tactical Director for four years, while he was a Major at the time. “I

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worked in The Hague Defense staff to focus on the future plans of the armed forces, and contributed to the document of the air traffic management renewal. Back then, I did not know that by the time the renewal would be put into action, I would be the commander at this base.” In 2011, he came back to AOCS, and after a while was named as commander of the base in Nieuw Milligen.

OPERATIONS AT AOCS, NIEUW MILLIGEN The AOCS NM is the organization responsible for military part of the Dutch airspace. The flight plans of all departing & arriving aircraft are known to the air operations command and all the traffic in the controlled area must inform the command.

As part of AOCS, there is the Military Air Traffic Control Centre, the Centre for Air Battle Management and Air Surveillance,

the school of Air control and the National Data link Management Cell. The latter is of great importance for all the armed forces, because they manage all data links, which you could compare to a Military WIFI network.

The base in Nieuw Milligen will be closed down in a couple of years, and the operations will be spread over four different locations. “What we should focus on is that the mission that we have is performed, and not so much the location from which this is done”, said the Colonel.

“The new structure of the air control is cooperation with both the Minister of Infrastructure and Environment, and the Minister of Defense. This is a structure we came up together, because we believe this is beneficial for the country. The new air space capacity on a European scale is very interesting for The Netherlands from an economical point of view. The coope-

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AOCS NM

AOCS NM

Figure 1. Colonel Henk Ras, Commander at AOCS

ration requires us to work together and side-by-side, also location wise, with our civil colleagues in Amsterdam”, he continued.

You might ask why the staff in Amsterdam cannot move to Nieuw Milligen instead, but the main reason is that they need to be close to the airport and for AOCS this move is less complicated. “Of course it is not an easy job to integrate the two cultures. We are in uniform and we are sent on mission, yet we have to be able to work together with the civil colleagues. The merge of any two organizations simply takes time and effort, and the same goes for us and I’m convinced we will manage to do this together.” As can be imagined, the merge will cause quite some changes in the lives of the people working at AOCS currently. “Spreading our men over the different locations is part of it. For some, their new work location will be ideal since they will be working closer to home, but for some this will be the opposite. Yet the Air Battle Control department which will be moving to Volkel will benefit from this change, due to the Lockheed Martin F-35 aircraft which are ordered.” The F-35 will also bring along some changes, as expected. “The main difference will be in the

training of the pilots and the simulation systems. The Air Battle Control, as initiated in the Second World War, started out as Air Defense and was mainly air-to-air related. But nowadays we see that air-toground is becoming even more important in e.g. Libya and Afghanistan, because there is no opponent in the air. The new technology and vehicles as the F-35 and the Reaper will bring a new phase of opportunities and allow operational cooperation.”

DIVISION OF THE BASE Even though the opportunities in the future are promising, the closedown of AOCS is not easy on the Colonel and his (wo)men. “Our goal the past couple of years has been to bring the Military Air Traffic Control and the Air Battle Management closer together. E.g., the School of Air Controllers has integrated the two trainings, and we have succeeded in work closer together. Just now when we have reached a period in which we start seeing the results of our effort in this merge, we got the news that it will be separated again. This is of course not easy. The military command part of the School will go to Volkel, we give a lot of importance to the instructors as they are operational controllers. The air traffic control part will go to Amsterdam.”

REGULATIONS AND SAFETY The new era brings along quite some changes for the cooperation between air controllers. But the Colonel is greatly optimistic. “Both the military and the civil air controllers work under the same European regulations, from training through operation. The current system is Eurcontrol’s Maastricht Upper Area Control, MUAC, and since we all play by the same rule, this will definitely not be a problem.”

SAFETY The international cooperation has started since the Second World War, and the air space is divided in different areas. The NATO Integrated Air Defense and Missile System is a chain of radio stations that work together and all have their NATO responsibility. “Whether we will be operating from Nieuw Milligen or from Volkel, our mission will not change. We are keeping our responsibilities in the international air space. Our air space connection with Germany, Belgium, Denmark and England will remain as it is with some minor changes due to the new system.”

2014 NUCLEAR SAFETY SUMMIT During the 2014 Nuclear Safety Summit, the Dutch armed forces worked together to secure the country, with safety measures for the ground, the sea and the air.

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AOCS NM AOCS NM

Figure 2. Air Operations Control Station in Nieuw Milligen

of six countries: Netherlands, Germany, Belgium, France, Luxembourg and Switzerland. The airspace is organized on a European rather than national basis.

This leads to improving the efficiency and major safety gains. Maastricht Upper Area Control (MUAC) airspace is one of the busiest in Europe with a complex structure and a significant portion of climbing and descending traffic. Operated by EUROCONTROL, MUAC provides air traffic control for upper airspace above 7,500 m of Belgium, Netherlands, Luxembourg and Northwest Germany. The lower airspace below 7,500m is managed by Belgocontrol, Luchtverkeersleiding Nederland and Deutsche Flugsicherung. Datainterchange systems are in place so as to ensure that both civil and military controllers obtain accurate information. The concept of Flexible Use of Airspace, according to which the military authorities release their airspace to civilian users whenever possible is used daily so that gains in capacity can be achieved.

NEW AIRSPACE STRUCTURE The government of Netherlands has developed a new vision strategy for the development of the Dutch Airspace in line with the developments in FABEC. A threevolume airspace concept with respective traffic management plans will be implemented.

1. Upper airspace volume (FABEC Northwest UTA): free route

Figure 3. Air controllers at work in 3D Tower Simulator

which we were working with in those days was not comfortable with this idea and we decided to take direct action. For the preparation of this summit, we have had the opportunity to learn from our colleagues in the United States, who must secure the White House at all times, and also in Brussels where the NATO meetings are held. The plans we made resulted in a blue-print for the Netherlands, which can also be used for future summits.”

FABEC AND MAASTRICHT UPPER AIR CONTROL The Functional Airspace Block Europe Central (FABEC) aims to implement multinational management of the airspace

2. Transitional airspace volume (CTA Holland): arrival and departure management When a fixed route structure around an airport can’t be linked to the free-route AOCS NM

“Leaders from 56 governments were in our country and special safety measures needed to be taken.” Though the Dutch air space was closed for air traffic, an airplane from Miami did fly into the zone. “Dutch fighters guided the aircraft to the airport in Frankfurt, where registration proved that there was no bad intention yet it was based on a mistake”, the Colonel stated.

“We had an international agreement regarding our air space, and if an aircraft fails to keep this agreement we must take action.” This action though, was initially seen as a possible threat. “The aircraft type was the same type as the missing Malaysia Airlines aircraft, and the Secret Service

In the upper airspace FABEC Northwest, air traffic is handled by means of the freeroute airspace concept. This has implications for the current ATS fixed route structure as it ceases to exist, enabling pilots to use most direct route and optimum flight profile. When specific military activities need to be separated from other traffic, a ‘segregated airspace’ will be activated locally for a temporary duration. This ensures a more efficient use of the airspace, ensuring optimal accessibility of Amsterdam Airport Schiphol and accommodating planned growth of regional airports of national importance.

Figure 4. 3D Tower Simulator

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Leonardo Times OCTOBER 2014

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AOCS NM

Figure 5. Military Air Controllers at AOCS

airspace, a transition airspace volume, CTA Holland can be established. This airspace volume is characterized by hybrid operational concept that focuses on controlling inbound and outbound traffic by means of arrival and departure management. Also, a cross-border military exercise area (CBA Land) will be put in place.

This is linked to the introduction of the fourth initial approach for the mainport Amsterdam Airport Schiphol, improving the airside accessibility of the TMA Schiphol (Terminal Manoeuvring Area) from south-east. A large portion of the military use of the airspace will take place in this area. The designing and the planning will be done on the basis of flexible airspace use. This is a complicated task requiring harmonization and precise planning.

3. Airspace around the airports (TMA’s): fixed ATS route structure The airspace around airports is characterized by a fixed route airspace volume, which ensures safe and efficient handling of traffic while taking into account the surrounding area. The policy is to separate all mainport related traffic in the lower airspace from other traffic. This is expected to facilitate further development of the

mainport as well as regional airports (Eindhoven, Lelystad and Rotterdam) while ensuring military effectiveness at the same time. Additionally, further simplification will be carried out by reducing four civil and six military controlled TMA’s to three integrated civil/military TMA’s: TMA Schiphol, TMA Holland Regional and TMA Liege- Maastricht (LIMAS).

TMA Schiphol maybe only reserved for IFR flights, specifically for traffic associated with mainport Schiphol. TMA Holland Regional will handle air traffic to and from regional airports and military airports. The traffic associated with mainport Schiphol will not be present in this airspace. Also, various general aviation users groups are present in this TMA. The border region in south-east of Netherlands has a complex airspace structure in which German, Dutch and Belgian airspace air traffic flows meet. In this area, several civil and military airports are located relatively close to one another. Other aviation related stakeholders are also present in this region. Considering the complex airspace structure, in part due to geography, the central government of Netherlands has opted for the cross-border airspace de-

sign and air traffic provision through TMA Liege-Maastricht.

With the planned defence budget cuts and a new vision for the Dutch airspace, the base at Nieuw Milligen will be closed and operations will be carried out as per new plan from four different locations. As all good things come to an end, so does the era of the Air Operations Control Station in its present form. But luckily, the new developments and changes will bring various opportunities and beneficial prospects. The military air control of the Royal Netherlands Air Force will continue to control and secure the Netherlands, and cooperate with allies to do so on both national and international level.

References [1] Colonel Henk Ras, Commander of AOCS, Nieuw Milligen [2] https://www.eurocontrol.int/muac [3] National Airspace Vision, Ministry of Infrastructure and the Environment, December 2012

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RVD NASA

ITAR AND THE FUTURE OF EUROPEAN SPACE How US unknowingly legislated itself out of the space race

In its efforts to remain the world’s superpower, the United States have installed a strict set of restrictions and controlling bodies to defend high tech military grade hardware.

By restricting European companies to use US origin components in certain satellites, it is quickly being eliminated from European based space products altogether. How will the future of the space industry in Europe and across the pond be influenced by US secrecy?

TEXT Elwin van Beurden, member Space Department, Student Aerospace Engineering

WHAT IS ITAR? ITAR or US “International Traffic in Arms Regulations” is a law that regulates and controls the export and use of parts specifically designed for military and space applications, administered by the US Department of State. ITAR can be applied really broadly and reaches far beyond US borders. ITAR is probably the toughest and broadest export control regulation in the world and is meant to maintain the technological edge of the US military and protect US interests.

Simply put, this means that when using US components, the US Department of State has to give approval prior to the export, reexport or re-transfer in a foreign country of any ITAR component. Simplistic parts, like bolts, could fall under ITAR when they are specifically designed for Military or Space applications. This means that a lot of parts from the United States, mostly parts that are available in Europe as well, can be ITAR components. Not only can this lead to delays and not being allowed to export the article, but it also poses a risk to the European space industry. Since ITAR, components are so stirringly regulated it is sometimes not possible to get documentation of the components, and if a component fails, it is hard to determine what failed and how to

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prevent it in the future.

THE SEE-THROUGH RULE Unlike other export regimes, ITAR does not have a minimum percentage of components to fall under ITAR. If a single part is ITAR, the whole product is. This means that if products meant for the commercial market contain a sub system with an ITAR component it cannot be sold without permission of the US. Since this is very hard to verify ITAR has the so-called ‘see through’ rule; seeing through the product to find any ITAR component. If due to a small component the product falls under ITAR, the manufacturer will either have to live with it or replace the component to make it ITARFree.

ITAR-FREE SYSTEMS With rising demand from emerging economies, like China, the space industry in Europe is at a crossroads. There are two options, do we as Europe continue to use American high tech components and all the benefits this generates or do we want to become a market leader and start creating more and more European components.

Some companies choose, for now, to use American components and cooperate

closely with the Department of State to strictly follow ITAR. There are however more and more companies that choose to create so called ITAR-Free systems; this is however a difficult process. Not only can the satellite not contain any US components, but also it cannot be built by American expertise or use any American sites. There are many tricks to avoid ITAR, but the only true way forward is eliminating any trace of US origin parts. This means that the whole value chain of the satellite needs to be clear of US parts. Therefore, all suppliers have to be checked for American parts, which is both a costly and time-consuming process.

Thales Alenia was fined eight million dollars last year for ITAR violations by its W3C satellite, since a subcontractor supplied radiation-hardened chips without registering them properly. Selling both ITAR and ITARFree systems can cause serious problems.

American authorities will force companies to supply detailed information about satellites if they are under the impression ITAR parts are used. If this information is not disclosed, access to the American market will be cut. This can have serious consequences for the acquisition of components as well as the loss of a major market.

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FUTURE OF ITAR According to a study by the space foundation, fifty percent of companies dealing with ITAR reported negative effects. In the report, a few recommendations are made.

First of all, the Space Industry needs to market itself better and show the nation it is an important economic asset as well as a key sector for national security. Secondly, the government should be aware that protecting the industry too much is harming it economically as well as losing the technological edge. By producing full non-US products knowledge and innovation is lost to Europe and other space faring nations.

There should be a proper balance between restrictions and economic benefits. In some fields, Europe has surpassed the US dominance in space, and by allowing it to slide further, technological supremacy will be lost to China and other emerging powers. This will also be damaging to Europe since it relies so heavily on US participation in NATO for its military security. Since West-

ern militaries are relying more and more on space technologies to operate, falling behind can be catastrophic. For both Europe and the US, reshaping ITAR should be a prime objective. Industry and legislators should together open the doors for international cooperation, and reduce the amount of paper work for exporting space technology while protecting critical technologies.

CONCLUSION There is not really a simple answer for ITAR. ITAR in its current form is damaging to US companies, while it challenges European space industry to innovate heavily to become independent of US products and services. If the United States wants to keep playing a major role in the space sector, it has to change its attitude towards its allies.

Opening up for more cooperation and only applying ITAR when there is a realistic risk to national security or the Americas’ technological supremacy is the rational path.

AVIATIONWEEK

WHAT DOES THIS MEAN FOR EUROPEAN SPACE? As we have seen replacing ITAR components to make the product ITAR-Free makes exporting the product a lot easier. Many markets that the United States restricts, like China, can all of a sudden be conquered.

This allows European companies to gain an edge over the United States when it comes to commercial satellites, as well as some military applications. Europe has been very dependent on the US for high tech parts, but winds are changing. Europe is already doing more and more herself and this will only increase. Consultancy firms are set up to supply European companies with the knowhow to eliminate ITAR from their production line and industry is trying its best to fill the gap. For Europe, this will mean a booming space industry and eclipsing the US as the most advanced space faring ‘nation’. With the production of ITAR-free systems, closer ties to China will be possible, opening up the doors to this rapidly growing market.

Figure 1. Itar Free satellites

CNSA

REFERENCES http://www.spacenews.com/article/ satellite-telecom/37071us-satellitecomponent-maker-fined-8-millionfor-itar-violations http://www.exportlawblog.com/ archives/3837 http://www.spacenews.com/article/ military-space/36706thales-aleniaspace-us-suppliers-at-fault-in-“itarfree”-misnomer http://worldecr.com/wp-content/ uploads/2012/07/ITAR-downloadarticle.pdf http://www.spacefoundation.org/ docs/SpaceFoundation_ITAR.pdf SPACE DEPARTMENT The Space Department promotes astronautics among the students and employees of the faculty of Aerospace Engineering at Delft University of Technology by organizing lectures and excursions.

Figure 2. Chinese Long March launch with an European ITAR-Free satellite

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Huub Timmermans

Forward Extending Flying Boom Changing the perspective of aerial refuelling The RECREATE project investigates the adoption of aerial refuelling operations for civil aircraft to achieve significant increase in overall fuel efficiency. The best approach, considering safety, cost and comfort criteria, suggests a flying boom extended from the trailing tanker, against airflow and gravity, towards the leading cruiser. This is approach differs from military aviation and raises the need of an innovative flying boom design.

TEXT Huub Timmermans (former MSc student Aerospace Engineering), R&D Engineer, National Aerospace Laboratory

O

ne of the novel operational concepts investigated within the European project REsearch on a CRuiser-Enabled Air Transport Environment (RECREATE) (http://www.cruiser-feeder.eu) includes the adoption of Air-to-Air refuelling operations for civil aircraft, which allows a reduction in take-off mass for the cruiser (passenger) aircraft. Preliminary results show a fuel burn reduction potential in the order of 15-20% for a typical 6000 nautical miles flight with a payload of 250 passengers, which can be achieved by simultaneously developing the whole operational concept and the design of dedicated cruiser and tanker aircraft.

While Air-to-Air Refuelling is standard procedure in military aviation, its adoption in civil aviation require higher standard of reliability and safety, and there is a need to account for other aspects such as passenger comfort and civil pilot training.

Incidents such as detachment and loss of the refuelling system, for example, could lead to catastrophic consequences. A preliminary study carried out at the Delft

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University of Technology indicated the convenience of inverting the position of tanker and receiver aircraft during refuelling. This configuration has (among others) the following main advantages: • Safety: The cruiser is flying ahead of the tanker, no hazard of collision with flying boom parts; • Safety: Tanker is able to immediately and safely separate in case of boom failures or other emergencies • Safety/Training: All refuelling work load (and required training) is for the tanker pilots, while the cruiser pilots need only to maintain speed and altitude; • Cost: By not flying in the wake of the tanker aircraft, less thrust is required. The tanker engines might be sized to fly at high speed and altitude while in the wake of the cruiser.

However, the need to use a flying boom (rather than a more compact reeling hose system) to limit the wet contact time and of keeping the whole cruiser cargo

area available for payload, as well as the convenience to install and maintain such complex systems only on board of the few tankers, raised the need of an innovative flying boom design, which is able to extend from the trailing tanker, against airflow and gravity, towards the leading cruiser. In parallel to this research, other RECREATE partners are investigating a more conventional (lower development risk) aft extending flying boom to use on the conventional configuration where the tanker aircraft is flying ahead and above the cruiser aircraft. This research is already in an advanced stage due to the low development risk. One of the investigations to see whether such a refuelling manoeuvre – routine for the military, but unknown still in civil air traffic - can be performed in a safe and efficient way, docking and refuelling manoeuvres have been flown in the advanced research flight simulators of NLR (in Amsterdam) and DLR (in Braunschweig), see Figure 1. Part of the work on the forward extending boom is to compare the new design with the convention-

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NLR

Huub TiMMERMANS

Figure 1. Commercial airline pilots performing a simulated aerial refueling maneuver. this image is taken from the cruise cockpit since this is the simulated conventional aerial refueling approach.

al design of the reCreAte partners and to increase the overall safety aspects of aerial refuelling within civil aviation.

FLYiNG bOOM SYSTEM: THE DESiGN SPACE the (reversed) flying boom system proposed in this article is actually based on a modified version of the conventional boom currently mounted on the boeing KC-135 Stratotanker (Langton et al., 2009). this boom mainly consists of a fixed and an extensible part. the fixed part is an 11.5m long tube featuring a low drag elliptical cross section and is stowed underneath the tail cone of the tanker aircraft during normal flight. the extensible part is another 10.0m long cylindrical pipe, which is stowed inside the fixed part during normal flight and extracted telescopically to perform refuelling. When both aircraft are ready to refuel, the boom is lowered from the stowed position and extended (maximum extension of 7.0m). A boom operator on board of the tanker, supported by a fly-by-wire system, can control the position of the boom by means of four movable surfaces, called ruddevators, which are collocated at the end of the fixed boom and can rotate around a spanwise axis, varying their incidence angle independently. the ruddevators are mounted in a V-shape arrangement such that the operator can control the boom, both in pitch and yaw, by varying their incidence (see Figure 2). this control authority, to-

gether with the telescoping movement of the extensible boom, allows the operator to fly the boom inside a certain 3D envelope, where the contact between the boom nozzle and the receiver receptacle can take place. to move the boom inside the 3D envelope, several kinematic solutions are of interest, each one yielding to different aerodynamic loads and reach envelope. the conventional kinematic solutions are the so-called lateral type, where the boom can rotate around a vertical/yaw axis, and the rolling type, where the boom can rotate around a roll axis. A third kinematic solution is based on a novel design patented

by Boeing (Ruzicka, 1998). This system requires one extra actuator to control the rotation angle of the boom around its longitudinal axis, as a function of the boom lateral and pitch angle. this allows setting the ruddevators at a convenient angle with respect to the airstream, hence limiting their required deflection (and size) to achieve the target control forces.

In this research work, a number of forward extending boom concepts have been considered, all based on a 4 ruddevators (2 of which are redundant) variant of the conventional solution, including the three kinematic solutions addressed above and accounting for both standard Aluminium and composite materials.

MuLTi-DiSCiPLiNARY OPTiMiZATiON DESiGN FRAMEWORK the main challenge posed by the proposed forward extending boom design is possibly related to the structural divergence problem. both the fixed part of the flying boom design (elliptical cross section) and the ruddevators are lift generating bodies, which will tend to bend under the effect of the aerodynamic load in such a way to further increase their angle of attack, hence the magnitude of those loads and the associated structural deformation. Obviously the interaction between aerodynamics and structure is of great concern here, because it could lead to catastrophic failures, or require too heavy structures, which, although feasible, could impair the achievable fuel saving. to this purpose, the stiffness matrix of several boom variants (based on the three kinematic mechanisms, in combination with Aluminium and composite material properties) was generated in symbolic form, as function of the main boom design variables, e.g. ruddevator surface area, length of the fixed boom, elliptical cross section dimensions, etc. Similarly, the aerodynamic matrix was defined, accounting for the different aerodynamic forces acting on the different boom variants (due to their kinematic solution). All details can be found in (timmermans, 2013).

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Huub TiMMERMANS

Figure 2. A forward swept boom mounted on a tanker aircraft. the boom is able to move inside the prescribed envelope by using the kinematic solutions and prismatic extending boom.

the setup of an mDO framework was deemed necessary to account for the large amount of involved parameters, disciplines (masses, aerodynamics, aeroelastics, control, etc.) and constraints, as well as the need to finally achieve the lightest possible solution. the various design parameters of the boom, namely the length of the fixed and extensible parts, the shape and dimension of their cross sections together with the size and shape of the ruddevators, all influence both the aerodynamic and structural response of the systems, in a non-trivial manner. the main challenge posed by the proposed forward extending boom design is possibly related to the structural divergence problem. to increase the divergence pressure, one would want to generate a circular cross section instead of an elliptical cross section for the fixed boom part, because a circular cross section would decrease the lift coefficient of the boom and increase the structural stiffness. However, a circular cross section would increase the drag generated by the boom, which would influence the size (and the weight due to the well-known snow ball effect) of the ruddevators. While the boom design could have been approached, in a first instance, just as a constraint-solving problem, it was considered whether to define a suitable objective function in term of weight, drag or a combination of the two. In the research, it was opted to go for minimum weight, because the tanker will always carry the boom weight

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during operations, while the aerodynamic drag is only presented when the system is extended. reducing the boom drag in the future appeared more easily obtained than reducing the weight of the total system, restricted by divergence pressure. the remaining constraints within the optimization are posed by the control forces (hence the maximum achievable lift coefficients of the ruddevators), structural divergence, as well as basic geometry (to guarantee a minimum separation distance between cruiser and tanker and the minimum boom cross section for adequate fuel flow rate).

CONCLuSiONS AND OuTLOOK From the mDO design framework, several feasible configurations have been derived for different combinations of material and kinematic solutions for the boom-tanker attachment joint. the proposed concept is Aluminium flying boom based on the roll actuated kinematic system, whose total mass and length are larger, but comparable to those of the conventional KC135 flying boom. this proposed concept appears to be feasible, fully controllable and free of static aero-elastic divergence problems. the subsequent development is analyzing the boom in view of dynamic instability, so called flutter. this is currently done at the National Aerospace Laboratory (NLr) to guarantee a safe operation using a forward extending boom for AAr

within the entire operating envelope. the flutter analyses are based on a simplified parametric linear Fem model using the model approach as implemented in MSC/ NASTRAN (Rodden et al, 2013). To find a feasible design space in which the proposed boom design is free from flutter, the boom concept from the mDO design framework is analyzed for various conditions and configurations (based upon the certification specifications for large airplanes). Preliminary results indicate that the forward swept flying boom can be designed to be free from dynamic instability. the developments in designing a feasible forward swept boom are positive and so far, no indicated showstoppers are presented. the next step would be the development of a suitable control system and to follow the research for the aft extending system by doing docking and refuelling manoeuvres in the advanced research flight simulators using the forward extending boom to increase the overall safety of civil aviation aerial refuelling.

ACKNOWLEDGEMENT the research leading to the results presented in this paper was carried within the project reCreAte (research on a Cruiser enabled Air transport environment) and has received funding from the european Union Seventh Framework Programme under grant agreement no. 284741. This publication reflects only the author’s views. the european Union is not liable for any use that may be made of the information contained therein.

references [1] r. Langton, C. Clark, m. Hewitt, L. richards, Aircraft fuel systems, Wiley, 2009 [2] D.e. ruzicka, “Actuated roll axis aerial refueling boom”, the boeing Company Patent US5785276 A, 1998 [3] H. timmermans, “Conceptual Design of a flying boom System for Air-toAir Refueling System of a Passenger Aircraft. Changing the perspective of Aerial Refueling”, MSc thesis report, TU Delft, 2013 [4] MSC/NASTRAN Aeroelastic Analysis.

User’s Guide. Version 68, W. P. Rodden, E. H. Johnson, The MacNeal-Schwendler Corporation, Los Angeles, CA

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04-Dec-14 21:54:12

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21

PHOENIX 5600

In an era where ‘time is money’, an opportunity exists to offer a unique value proposition to customers by developing a Premium Light Business Jet, the ‘Phoenix 5600’. This jet sets itself apart from the competition by combining flight speed in the transonic domain with short take-off and landing capability. Together, these aspects are expected to result in a significant decrease in travel time while maintaining point-to-point travelling. Simultaneously, sufficient capacity and comfort should be retained to be competitive in the light business jet market.

DSE – GROUP 21

TEXT DSE group 21

MISSION Business jets are available for a wide range of performance and capability requirements. From a customer perspective, the use of business jets for air transport offers many advantages instead of using business- or first- class options offered by airlines. Flexibility, time saving and productivity ensure that the customer is not constrained by airline schedules and can travel at virtually any required time, have the capability of flying point-to-point and allow for meetings and conference calls.

OPPORTUNITY Between 2013 and 2023, 9,250 new business jets will be produced in the light-medium business jet class, which is equivalent to $260 Billion. This is a great opportunity and according to the market analysis Asia and America will be our main markets.

PREMIUM With a range of 5,600km all continental destinations of Asia and America can be reached, as well as all inter-continental destinations between America, Asia and Europe. With a cruise Mach number of 0.90 and a maximum Mach number of 0.95 the competition is overruled to ensure the

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shortest travel time as possible for our customers. With a short take-off and landing distance of 819m and 746m respectively, point-to-point travelling is ensured. Flying at a cruise altitude of 41,000ft, no nuisance of the commercial airlines will be experience and with a cabin altitude of 1,500m ISA equivalent maximum comfort is guaranteed for our customer. Finally, the comfort of the Phoenix 5600 is significantly higher with 60dB cabin noise, which is comparable to the noise in an average meeting room. The cabin is equipped with high-tech technology features to enable comfortable meetings and conference calls. Due to the premium seating with a width of 60cm, 6-8cm more than most business jets, customers will experience unparalleled comfort.

DESIGN Starting with 13 configurations a preliminary design was performed and on 4 of these a Class I design was performed. One design was chosen to perform a Class II design on; a forward, cantilevered, swept, low wing aircraft with airfoil NACA 64212 Mod B with Fowler flaps as high lift devices, a canard and a T-tail to ensure the light weight of the business jet of only 9,100kg

(MTOW). The maximum payload is 980kg, for an eight-passenger configuration, with two crewmembers and 180kg of baggage.

With the two aft placed Pratt & Whitney PW 545C engines a cabin noise of 60dB can be ensured.

FINANCIAL PROSPECTS AND SUSTAINABILITY The Phoenix 5600 will be ready for operation in 2020 and with a list price of only 16M$ and an operating cost of only 2,400$/h it is relatively cheap to purchase and operate. With the focus on sustainability, to meet the needs of the future aerospace industry with a lower impact on the environment the design team was pushed to come up with innovative solutions.

The Phoenix 5600 is a sustainable aircraft, which complies with all FAR25 regulations.

CONCLUSION In conclusion, the Phoenix 5600 premium light business jet offers the business market, a fast, reliable and cost-effective way of transportation without compromising comfort and sustainability, from 2020 onwards.

Leonardo Times OCTOBER 2014

04-Dec-14 21:56:16

20

ANTARCTIC WIND TURBINES

NASA

The Antarctic region is a priceless asset to the world with its unique wildlife and can provide great insight for all those studying climate change and the climate systems of the Earth. Due to its importance, thousands of scientists and supporting staff live and work in research stations at any given point on the Antarctic land. One of these research stations is the Signy station located on Signy Island. It has been occupied since 1947 and mainly biological research is performed. For their operations, a sustainable wind energy system is required to ensure a proper energy source, for now but also in the future.

TEXT DSE group 20

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he main focus of the design is to withstand and use the special environment of Signy to provide a sustainable energy supply for the research center. The fragile Antarctic environment is taken into account during the design process, conforming to the Antarctic Environmental Protocol. Signy Island has a very special environment, the temperatures range between -38°C to 10°C and it experiences wind speeds up to 58m/s. Due to the high wind speeds Signy is an excellent location for wind turbines. In this article, we will present our solution, the Windpulse.

The Windpulse is a horizontal axis wind turbine (HAWT). HAWT design is a lift driven device and as such the most commonly implemented wind turbine system around the world.

To comply with the power demand of the Signy station, three horizontal wind turbines of 17kW each are the most reliable and cost efficient option. To avoid noise and interactions the turbines are placed 70m from the research station with a spacing of 44m in-between the turbines. The rotor of the Windpulse consists of three blades of 4.4m each and has a downwind configuration. The blades have a variable pitch and rotate with variable speed. The

airfoil-shaped rotor blades have an optimum twist and chord distribution and are internally supported by stiffening elements, which are able to withstand all forces exerted on the blades. The blades are made out of a hybrid composite using flax and bio-based epoxy, which is a sustainable material. To avoid bird collisions one blade is painted black to trigger the bird’s retina. Ice attached to the blades causes a serious decrease in aerodynamic efficiency, so a de-icing system is needed. An efficient and low power consuming system is used; the pulse electro-thermal de-icing system. This system uses a millisecondlong electrical pulse directly applied to the ice-covered surface. The rotation of the blades is converted into electrical energy by use of the shaft and a permanent magnet direct drive generator cooled with a passive cooling system. These parts are protected from the environment by a nacelle housing which provides the least amount of drag. A tapered 8.8m tower is supporting the complete rotor and nacelle and is designed in such a way that it can handle all load cases. A rock anchor foundation fixes the wind energy system to the amphibolite ground with 8 anchors with a length of 2m.

In order to store the power produced a lead-acid battery system is placed next to the research center, this system is 98% recyclable. In case of an emergency the diesel generator, which is now the energy system of Signy, is used as back up.

The total cost of the wind turbine system is estimated to be €642,000 which gives an electricity cost of €0.14/kWh. During the process the carbon footprint was used to minimize the carbon emissions. The wind turbine system has a carbon footprint due to the implementation of the system of 782,600kg CO2 over its entire lifetime, including batteries and emergency use of the diesel generator. For comparison, the diesel generator has a carbon footprint that is 3.5 times higher than the Windpulse.

In conclusion, the wind turbine system consisting of three Windpulse systems can withstand the Antarctic environment and provides energy to the Signy station in a sustainable way. Let us work towards a more environmentally friendly power system on this barely touched and seen continent, where Mother Nature hides her most fantastic wonders, starting with our wind turbine system at Signy Island.

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06

BIRDPLANE

Barnacle Geese migrate over 900km non-stop with remarkably high efficiency, unreached by any man-made aircraft in history. While they are flapping their wings, they also simultaneously fold, twist, and morph the wings to maximize the aerodynamic forces and increase the flight performance. Until today, their exact flight mechanics and dynamics have not yet been fully comprehended. The decryption and mimicry of bird flight has therefore been a long-lived dream of humankind and is believed to be a possible answer to current aviation challenges. In pursuit of acquiring better insight into the migratory birds’ flight behavior, BirdPlane came to life.

PROJECT & MISSION OUTLINE A group of ten bachelor students have dedicated ten weeks of time to design BirdPlane, a unique flapping-wing aircraft that can fly alongside the migrating Barnacle Geese. In order to be accepted by the other birds, BirdPlane will need to combine as many bird-like features as possible. It also needs to keep up with the birds, which can fly up to 90km/h.

A typical mission of BirdPlane will start with the detection of a flock of Barnacle Geese through radar on the ground. A rendezvous strategy was developed to meet and merge with the flock with low battery usage. During formation flight, BirdPlane will gather scientific data, which would allow bird researchers to study the birds’ flight behavior. Once the mission ends, BirdPlane will approach the nearest of the predetermined landing sites and autonomously touch down.

AIRCRAFT DESIGN Due to its similar shape, size and natural wing movement, BirdPlane will blend into the flock and fly with the Barnacle Geese without raising suspicion. The wings are capable of three motions - vertical flapping, span-wise folding and twisting - providing the required lift and thrust, excluding conventional propulsion systems. In order to make quick turns and accurately maneuver

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inside the flock, BirdPlane will be equipped with a bird-like two-axis rotatable and fanning tail. For gliding flight or turns, the tail is fanned-out increasing control forces, while in cruise the tail is fanned-in for drag reduction.

Internally, an innovative mechanism uses a sophisticated gear system to convert the rotation of only one electric motor into the complex wing motions. A planetary gearbox is used to adjust the flapping motion in-flight to maximize aerodynamic efficiency.

Precautions for safe landing are taken by implementing a “Smart Rubber” on the belly (Leibler, 2008). This material has the advantageous dampening properties of normal rubbers while also possessing remarkable self-healing properties: A cut in the surface will be closed within seconds.

FUNCTIONALITY Aside from the flight performance, BirdPlane also provides high-level functionalities to successfully accomplish the given mission. The subsystems, which are directly related to such functions are: power supply, communication, navigation and controls subsystem. To provide sufficient power throughout the mission, Li-S batteries are chosen to be used due to their high specific energy. The communication link between the ground station and BirdPlane is estab-

TEXT DSE group 6

lished through a ground antenna network (short-range) and the mobile phone network (4G, long-range).

Furthermore, in order to autonomously follow the flock of geese, BirdPlane detects the geese using a stereoscopic infrared camera setup with reliable depth perception. To stabilize the camera footage, an iso-elastic neck is incorporated to decouple the motion of body and head. The Navigation subsystem defines waypoints autonomously, which are fed into the control loops of an on-board autopilot. Finally, the autopilot actuates the main engine’s RPM and control surface deflections in response to the target set-point, based on PID controller dynamics.

CONCLUSIONS After the iterative design process, a detailed performance analysis was carried out and verified that the current design of BirdPlane would be able to fulfill most of the key requirements without having to compromise on the initial design goals. To our surprise, some of the design outcomes even suggested that BirdPlane can potentially perform better than the primary expectations in terms of flight capabilities and functionalities. Such results led us to believe that the development and application of BirdPlane can set a milestone in the field of flapping-wing UAV technology.

Leonardo Times OCTOBER 2014

04-Dec-14 21:56:25

T-WRAX

01

Behind a wind turbine there is a region of air with a lower speed than the free-stream wind and with increased turbulence. This region is the wake. In a wind farm, the wake from one wind turbine can interfere with the wind turbines placed downstream of this turbine, which decreases their efficiency and increases the dynamic loads acting on them. To optimize the layout and control of wind farms, it is important to be able to measure the locations of these wakes to validate wake models. This is what T-WRAX does.

TEXT DSE group 1

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he goal of this DSE project was to track meandering of wake boundaries of a wind turbine during a considerable time period at on- and offshore wind farms, using a low-cost, stand-alone, durable and recyclable system. To achieve this goal many different design concepts were created, ranging from flying UAVs with anemometers around the wake to inserting smoke from a smoke machine into the wake and tracking this smoke with a camera. After the exclusion of the unfeasible design, a trade-off was made with the remaining options. The selected design option is radar. Radar is a mature technology that has already proven itself for atmospheric measurements. Radar is a relatively small and lightweight system that uses little power and, surprisingly, it is very cheap. The name T-WRAX is an acronym that stands for Turbine Wake Radar in X-band.

Radar works by transmitting radio waves.

These radio waves are reflected by objects in the path of the radar beam. These echoes are then received by the radar system, from which the distance and velocity of the object relative to the radar can be determined. With this information, a complete two-dimensional velocity field can

be constructed. Using a definition for the wake boundary, for example that the wake begins where the air velocity is 95% of the freestream velocity, the wake can be found by the radar system.

For the design of a radar system the most important characteristic is the minimum detectable object or, in the case of an atmospheric radar, the minimum target reflectivity. It is possible for radar to measure clear-air turbulence, but this requires very sensitive radar. It was determined that for our situation it would be best to use fog as the minimum reflectivity. As long as there is fog or any type of precipitation the radar system will be able to operate.

To be able to detect fog sensitive radar is still required. To achieve the required sensitivity a radar system with two dish antennas is used: one for transmitting, the other for receiving the radar signals. Since the radar system is designed to measure in a two-dimensional plane, T-WRAX must be placed on the wind turbine nacelle to be able to measure the wake. This can be done in two ways: if the wind turbine has a platform, T-WRAX can simply be placed on this platform. Otherwise, it can be sus-

pended below the nacelle, by attaching it with ropes to the safety rails on top of the nacelle. These rails are used to secure service engineers during their work. Since the T-WRAX is relatively lightweight, they should be able to hold the T-WRAX without problem.

The most important alternative measurement techniques for measuring wind turbine wakes are Lidar and Sodar. Sodar uses the reflection of sound waves to create a velocity field and Lidar uses the reflection of light. Compared to Sodar, T-WRAX is significantly more accurate and it provides more usable data with a higher acquisition rate. On top of that, T-WRAX is significantly cheaper. Lidar on the other hand does have a higher accuracy than T-WRAX and is smaller and lighter, but it is also very expensive, ten times more expensive than T-WRAX or even more. T-WRAX might not be the absolute best measurement system, but it is definitely the cheapest one. We think that radar can do a big contribution to the scientific knowledge on wind turbine wakes and we expect radar to be used more commonly for wind turbine research in the future.

OCTOBER 2014 Leonardo Times

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02

HIRES

DSE S2

A modern air force experiences an increasing need for Intelligence, Reconnaissance, and Surveillance (IRS) information due to the emergence of new warfare technologies, like UAVs and high-precision targeting devices. This need is summarized by Robert Gates, former US Secretary of Defence: “The most advanced fighter aircraft are of little use if one does not have the means to identify, process, and strike targets as part of an integrated campaign”.

Having to rely on external parties in obtaining this information, the Royal Netherlands Air Force (RNLAF) requested assistance from the TU Delft to explore the possibility of an independent IRS space asset.

TEXT DSE group 2

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mergency planning and operations, environmental monitoring, and homeland security are one of the many civilian applications for images taken by Earth Observation satellites. With present technology, high-resolution photos from locations all over the globe can be taken within hours of notification. The military finds use in these pictures as well, especially for high value target investigation, detailed operational planning and object identification. It is for this reason that the RNLAF is looking for an economical, lightweight, and high-performance space asset. However, current high-performance IRS satellites are generally heavy and cost hundreds of millions of euros. Finding an innovative yet reliable solution was key to this project.

The unique solution to the proposed problem is HIRES, which stands for Holland’s Intelligence, Reconnaissance, and Earth Surveillance. HIRES uses two identical imaging payloads combined with an image enhancement technique to provide panchromatic images with a ground resolution between 0.5m and 0.9m. These resolutions can be achieved in a total of five different imaging modes, for example by taking simple 1km x 1km images or do large strip searches of 17.8km x 200km.

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Per day, a total of 12500km2 can be send down using a ground station in Vardø, Norway. For added flexibility it is also possible send images to any location on Earth through mobile ground stations deployable by the military, in under ten minutes.

The uniqueness of HIRES lies in using an image enhancement technique called superresolution. Superresolution is a postimaging processing technique using data interlacing, and interpolation, of multiple images to achieve image resolution enhancement. Used on the SPOT-5 satellite since 2002, this technique is capable of enhancing the image resolution of a single payload (0.9m) to a high-quality image with 0.5m resolution. Basically, the two payloads are calibrated to nanometer level such that they take image samples with an offset of 0.5m in both the lateral and axial direction with respect to each other.

Once these images have been transmitted to Earth, interlacing of the samples and interpolation of intermediate data points results in an overall resolution of 0.5m. Even though this technique has only been used and proven on one satellite so far, its potential enables HIRES to be much lighter and cost-efficient as compared to conventional Earth observation satellites.

HIRES orbits Earth in a 565km Sun-syn-

chronous orbit (SSO), which is determined to be optimal for the payload performance and global coverage. Moreover, the SSO simplifies analysis of the images as the Sun incidence angle is constant throughout each orbit. On-board resistojets provide HIRES with enough ∆V to cope with orbit injection inaccuracies, and to guarantee a minimal lifetime of 3 years. Due to its altitude, the spacecraft is expected to end its life within 20 years upon re-entry in the atmosphere, thereby leaving no space debris behind. With a total mass of 224kg and based on mostly off-the-shelf and ITAR-free components, HIRES can be developed and launched before 2018 for a total cost of only €25 million.

An economical, lightweight and highperformance space asset that is what the RNLAF was looking for, and that is exactly what they got. HIRES promises a reliable, independent platform for Intelligence, Reconnaissance, and Earth Surveillance by combining the superresolution technique with space proven components, all integrated into a single 224kg spacecraft.

With this platform in their military inventory, Holland’s integrated campaign as described by Robert Gates will have propelled itself into the space domain.

HIRES, your eye in the sky

Leonardo Times OCTOBER 2014

04-Dec-14 21:56:38

03

ASAP UAV

I.M. DELFT

The Search and Rescue (SAR) of victims at sea remains hazardous and requires an innovative and safe solution. In 2013, volunteers of the Royal Netherlands Sea Rescue Institution (Dutch: KNRM) performed nearly two thousand missions rescuing over three thousand people, risking their lives doing so (KNRM, 2014). This risk to SAR-personnel can be decreased significantly by deploying Unmanned Aerial Vehicles (UAVs). However, most existing UAVs are incapable of operating under extreme weather conditions or are economically unviable. The optimal solution combines a cost-effective design with all-weather search capabilities.

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urrent UAVs designed for adverse weather conditions can only operate up to five or six Beaufort, while SAR missions today are performed up to twelve Beaufort. These wind conditions can generate waves up to fourteen meters high, making naval operations difficult to say the least. Air support during SAR missions is currently provided by SAR helicopters, which are expensive to maintain and operate while the crew is put at risk repeatedly. The Autonomous Search All-weather Polymer (ASAP) UAV aims at fulfilling the search role of the SAR Helicopter in future missions.

The ASAP UAV is able to operate in continuous wind of nine Beaufort and sustains gusts up to twelve Beaufort. Furthermore, the UAV will be extremely water-resistant due to a hydrophobic coating and watertight seams, allowing the UAV to perform the search mission in virtually all weather conditions. The entire airframe consists of a bio-based polymer composite, consisting of Poly-Lactic Acid (PLA) resin with 30vol% chopped flax fibers, novel to aerospace industry. The in-flight deflections and stresses that will act on the structure are well within the allowable bounds of the composite. The polymer-based lithium

batteries will be placed inside the wings, providing bending relief within the wing structure.

The compact design of the ASAP UAV will allow for a quick launch from medium sized ships using a Troy catapult system.

Once launched, the UAV will be able to search for three hours at its cruise velocity of 105km/h using its electric single-prop motor at the trailing edge. A see-and-avoid system is incorporated in the nose of the airframe to prevent mid-air collisions. Other internal systems are the flight computer, a Guidance Navigation and Control (GNC) system and the communication systems.

The onboard imaging system is able to record visual footage during daytime operations and thermal imaging at night or in low visibility conditions. Once a victim is located, an emergency signal is sent to the nearest rescue vessel and a slow circling flight is initialized to keep track of the victim until the arrival of a rescue team. In case of wind velocities above 22m/s the UAV will fly at matching velocity in headwind, hence remaining nearly stationary above the victim. The operating altitude is between 50 and 150 meters, which is safely below the minimum operating altitude of local regional aircraft and above the maximum

altitude of recreational kites. The end of a mission, whether successful or not, will be concluded by a belly-landing on the water surface for safety reasons. During this landing the reinforced bottom fairing absorbs the major impact. The floating ASAP UAV can be easily recovered, maintained and sent out again for the next mission.

The impact at landing will cause the propeller to break off and sink to the bottom.

These propellers are cheap, easy to manufacture and completely manufactured from the biodegradable PLA/Flax composite. Almost a third of the ASAP UAV mass is biodegradable which decomposes in water within 18 months. Virtually all of the remaining components can be fully recycled, keeping the total waste to a minimum of only 5%.

In all aspects, the design is sustainable and harmless to the environment. Using electricity from renewable sources to maintain this high degree of sustainability should perform the charging of the batteries.

Compared to the existing UAVs the outstanding performance of the ASAP UAV is not compromised by a hefty price tag. It is an affordable solution to an unaffordable problem: the loss of human life at sea.

OCTOBER 2014 Leonardo Times

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05

A320 ALTERNATIVE FUEL

The aviation industry is booming. The amount of passengers in aviation is increasing each year. A big hurdle in its growth is the availability of cheap and sustainable fuel. Oil reserves are decreasing more and more every year, resulting in a significant increase in kerosene price. Therefore, an alternative fuel is required. Liquefied Natural Gas (LNG) is an attractive alternative fuel since it is cheap, less polluting and can be made easily available.

T

he objective of the project was to design the next generation sustainable A320, capable of using LNG, for the year 2030. Special emphasis is put on sustainability to meet the growing global awareness of environmental issues. The current A320 is taken as a baseline and the new design is required to have the same or better performance characteristics.

The proposed design is a hybrid solution operable on both LNG and kerosene. 50% of the fuel capacity is LNG and the other 50 percent is kerosene. For airports close to existing natural gas pipelines a small-scale liquefaction plant can be used in order to liquefy the natural gas on the airport itself.

However, the infrastructure needed for a LNG supply to all airports will not be available by 2030. In case no LNG is available, the airplane can still fly on kerosene due to its hybrid design.

The final design is able to reduce CO2 emissions by 50%, NOx by 75%, SOx by 100%, if completely flown on LNG, and noise by 25%. Furthermore, it will not increase the

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effect of water vapor on the Global Warming Potential (GWP). All these reductions are in line with the emission goals set by ACARE (Advisory Council for Aviation Research and Innovation in Europe).

This is achieved by having open rotor engines instead of turbofans. These engines have increased energy efficiency and thus reduce the specific fuel consumption. They are placed at the back of the aircraft where use is made of an H-tail. This tail is chosen because it provides shielding of the noise, which is an issue concerning open rotor engines, hence less noise pollution will be emitted. Furthermore, it provides redundancy in case one of the blades flies off and hits one of the vertical tail surfaces. In the event of a blade flying off, the fuselage is reinforced in the back such that it can withstand the possible blade impact and no catastrophic flight conditions occur. To accommodate this carbon-kelvar is used.

TEXT DSE group 5

kerosene. Therefore, to achieve the same range, a larger tank volume is needed. LNG is stored in the fuel tank at cryogenic temperatures. This requires special insulation in order to minimize the amount of heat transferred to the LNG. New tanks are designed which are located underneath the wing. These two wing pods are insulated by a specially developed aerogel for cryogenic conditions: Cryogel-Z. Both inner and outer tank wall are made of aluminum.

Furthermore, a new wing is designed and the wing and tail are sized and positioned such that the stability and controllability requirements are met.

Compared to the current A320-200, the direct operating costs decrease by twelve percent, which is mainly due to the cheaper price of LNG compared to kerosene. This makes the aircraft not only more environmentally friendly but also makes it more attractive to operate for airlines, resulting in cheaper air tickets.

The aircraft requires several other changes when flying on LNG. LNG has a lower energy density (Joule per cubic meter) than

Leonardo Times OCTOBER 2014

04-Dec-14 21:56:48

careersathmc.com

Is it really the blue sky you’re dreaming of?

At Heerema Marine Contractors (HMC), we see a lot of

Quite frankly, the circumstances to cope with at 10,000

blue. Blue seas around the world, and blue skies on the way

ft depth may be a lot more extreme than what you’ve

there. What we do is not exactly rocket science, but we

prepared for at 30,000 ft up in the sky. So if you are looking

come pretty close. We design, construct and install mega

for a sky high career perspective, you may want to consider

structures for the offshore oil and gas industry. Platforms

landing at HMC. The oil and gas industry is booming and

and oilfield infrastructure for operation in shallow waters or

provides new, magnificent engineering challenges every

at depths of several kilometers on the seabed. The deeper

year. Plus a tremendous responsibility for the safety of man

the oilfield, the more high-flying engineers we need to

and the environment. And the tools we use are pretty cool

conceptualize, calculate, design and innovate towards future

too. Our largest crane vessel Thialf has a lifting capacity of

groundbreaking and record-setting projects.

about 50 Airbus A380s. Just so you get the picture.

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Check in for a test flight at: careersathmc.com

07

VOLUCREM -THE FLYING CAR

DSE GROUP 7

Throughout history, there has always been a need for transportation. People are impatient beings and desire a minimal door-to-door time. In 1903, the Wright brothers started the flying revolution. Ever since, travelling time has decreased. However, in recent times a stagnation of this trend is visible. As current life demands a quicker life style than ever before, a method of travel is sought that is even quicker and even more versatile. Hence, concept of the flying car, Volucrem has been designed.

TEXT DSE group 7

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his design synthesis exercise group aims at the development of a modular flying car capable of both flying and driving while leaving all flight critical elements at the airport. This results in a minimized dead weight when driving on the road and minimizing the risk of damaging flight critical elements. This could create a possibility of living in rural areas while working in the big city; a paradigm shift in transport is within reach.

Currently, distances up to 1000 km can be travelled by car but this is a time-consuming method of transportation. One can also go by plane. However, waiting times are longer than the flight time for these distances. The flying car on the other hand, can be converted within half an hour, has independency of airline routes and can take off and land at all preferred airports.

The trip starts when the customer steps in the three-wheeled carver and drives to the airport. The driving is not comparable to that of a normal car though, it banks in a similar manner to a motorcycle by using the DVC system (Carver Technology). This

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way driving is more like flying. Furthermore, the car has a diesel engine designed for the smart car, which has 58kW of power and consumes 4.3L per 100km. The car has automatic transmission and can be steered by an M-yoke, similar to the one found in a Concorde. Throttling and braking will be done in a similar manner to a motorcycle.

The car will be 4 meters long, have a width of 1.2 meters and a height of 1.5 meters.

Moreover, it will weigh approximately 465 kg, including the weight of the fuselage including roll cage, furnishing, electronics, cockpit systems and the engine for the car.

Once at the airport, the customer will attach the wing module where the attachment is based on three ball and socket joints. These joints will be locked using electro hydrostatic actuators, which then will be mechanical secured if the hydraulics would fail. The attachment system is designed to withstand 8g. Furthermore, the cables for the power by wire system should be connected and the mirrors should be stored inside in cabin. When all this has been done, the flying car is ready to taxi during which the pre-flight checks can be performed.

During take-off the flying car will accelerate to 36 m/s, at which it will rotate. It will then retract its landing gear to a position in which they minimize drag. The flying car will climb to an altitude of 7000 meters for cruise. At this altitude pressurization is required, which will be done by the turbocharger of the car engine. The cabin altitude will have a pressure equivalent to the pressure at 2500 meters, which is comfortable for all passengers. The flying car will cruise at a true airspeed of 212 knots to its destination. The flight module would accommodate an 180kW turboprop engine weighing only 57kg which uses a two meter diameter push propeller. The wing area is around 13m² with an approximately elliptical lift distribution. The total unit price would lay around 500,000 Euros including both the flight and car module.

In conclusion, Volucrem will provide the business market a fast and flexible solution capable of reducing door-to-door time making it possible to live in rural areas while working in major cities. A paradigm shift in transportation could be made including the comfort of a personal air and drive vehicle at a relatively low cost.

Leonardo Times OCTOBER 2014

04-Dec-14 21:57:54

10

LUNAR SAMPLE EXTRACTION CRYOGENIC RETURN MISSION

DSE GROUP 10

The Moon: a familiar sight to all. Ever since the dawn of humankind, myths and theories have been put forward to try and explain her presence in the night sky. To test the current theories on her creation, detailed knowledge of the chemical composition of the lunar soil is needed. The Lunar SECRet mission has been designed to recover this information. It will extract a two meter deep drill core from a dark crater at the lunar south pole, store this sample at 120K to prevent loss of the volatiles captured in the ice and return it to Earth for the scientific community to analyze.

TEXT DSE group 10

SPACECRAFT DESIGN For the design of the spacecraft, inspiration is taken from the Apollo mission: the Lunar SECRet spacecraft is composed of an orbiter, re-entry vehicle and a lander (composed of an ascent stage and descent stage). The ascent stage contains the propellant and the engines for both braking and taking off from the lunar surface.

This way no extra propellant tanks and engines are needed in the descent stage which saves propellant mass. The descent stage contains a fuel cell and a drilling system based on the ExoMars drill. The drill can sample two meter of lunar rock in parts of ten centimeters. Using a robotic arm that is fitted to the ascent stage, the samples are transferred to the cryogenic system (which is also contained in the ascents stage). The descent stage provides a three-legged platform from which the ascent stage takes off. The orbiter contains the propellant for inclination changes and the journey back to Earth. From within the crater there is no direct line of sight with Earth, so the orbiter is fitted with a communication system to communicate with Earth. In order to cope with the thermal loads an ablative heat shield was designed for the re-entry vehicle using phe-

nolic impregnated carbon ablator (PICA) which is a low density heat shield material. This ensures the temperature inside remains below operational limits of the cryogenic system.

Furthermore, the whole cryogenic system is designed such that it can be transferred from the ascent stage to the re-entry vehicle by the robotic arm contained in the ascent stage.

CRYOGENIC SYSTEM To preserve the sample in compliance with customer requirements, it needs to be stored at temperatures below 120K at all times, up to twelve hours after re-entry.

To ensure the sample remains at cryogenic temperatures a reverse-Brayton cryocooler is used. In space, the cooling liquid used by the cryogenic system rejects heat into space using radiation. However, after re-entry, whilst in the atmosphere, this is not possible. Therefore, a heat sink is used here to absorb the heat from the cooling liquid. This system allows for the extraction of large quantities of energy from the cooling liquid, without heating up notably. The thermal power input drastically increases in atmospheric conditions due to convection and conduction. An aerogel insulation layer is therefore used as thermal insulator. The cryogenic system, which is normally a closed and insulated system, is designed to be able to open up and receive samples from the robotic arm.

MISSION OVERVIEW The spacecraft is launched into a translunar injection using a Falcon Heavy launch vehicle that will be operational before 2025. Upon arrival at the Moon, the lander (composed of the ascent stage and descent stage) descends towards the Wiechert J crater on the South Pole, where the samples are retrieved. The ascent stage uses the descent stage (which is left behind on the lunar surface) as a platform to launch from the Moon. Once in orbit it will dock with the orbiter and the cryogenic system including the samples are transferred from the ascent stage to the re-entry vehicle. The orbiter will then initiate a trans-Earth injection and the ascent stage is left behind in lunar orbit. Upon arrival the orbiter is left to burn up in the atmosphere while the re-entry vehicle descends and lands safely in Kazakhstan.

The mission will have a total life-cycle cost of â‚Ź477 million.

OCTOBER 2014 Leonardo Times

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12

PRINTING THE AIRCRAFT OF TOMORROW

Not a day goes by without reading something about 3D printing or Additive Manufacturing in the news. Currently, all sorts of things are being printed: from jewelry to houses, from cast braces to jaws and from UAV’s to complete aircraft. Unfortunately, this last part is not yet true and that is where DSE group 12 comes in. The goal of this team was to design a complete airframe for a personal aircraft (in the LSA category) using Additive Manufacturing technologies.

TEXT DSE group 12

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dditive Manufacturing, more commonly referred to as 3D-printing, is a production technique that is based on adding material to a part, instead of subtracting it, like milling. Manufacturing parts in such a fashion provides immense freedom of design and thereby the opportunity to realize structurally and aerodynamically efficient designs. This enormous design freedom is of course a huge advantage, but it does come at a price. The variety and large number of possible solutions can slow down the concept development and selection process.

And contrary to what is often believed, one cannot print simply anything. There are many limitations in, for example, wall thickness, tolerances, overhanging structures and the maximum build envelope.

To exploit the benefits of Additive Manufacturing to the fullest and to cope with the new design environment, the team developed a unique concept selection process.

Starting at a component level, the possibilities of specific materials and manufacturing processes for structural aircraft components were investigated. This knowledge is combined in multiple aircraft configurations of which the most promising one is selected and subsequently broken down into its constituents to perform detailed design.

From this unique concept selection process,

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a tandem wing concept emerged as best suited to both the advantages and disadvantages of Additive Manufacturing. In particular, the build volume constraints were a major design driver. Separating the lift generation over two lifting surfaces provides a set of advantages: Structurally, bending loads on the wings are significantly reduced, minimizing the loads on the joints that are required. For increased aerodynamic efficiency, both planforms are elliptical, which is easy to create using Additive Manufacturing, contrary to conventional manufacturing techniques. An in-depth CFD investigation using the OpenFOAM software has indeed shown that this estimated increase in aerodynamic efficiency has been achieved.

During the detailed design phase, the influence of the advantages and limitations of Additive Manufacturing became even more apparent. Sizing unconventional design solutions proves to be a complex, time-consuming process. The team overcame this hurdle by adopting two design philosophies: a fully, computer-aided design approach and a more conventional design approach where established sizing methods are used. In this last design approach the results are subsequently adjusted to draw larger benefits from AM, for instance by numerically optimizing the shear panels in the

fuselage structure. Due to time constraints, this design approach was used for most of the structures, including the fuselage, engine mount and landing gear.

In the first design, philosophy the team used Topology Optimization (TO) extensively. Such a TO algorithm uses a CAD model defining the design space, performs a FEM analysis, removes the superfluous material resulting in a new CAD model and iterates until an optimized design is found. In the project, it was decided to use the Abaqus Toplogy Optimization Module (ATOM).

The result of such a design approach is an organic-looking, optimized structure which can easily be resembled using Additive Manufacturing technologies. This design approach was only used for the vertical tail and the wing root sections due to the vast amount of time required for this approach.

Concluding, Additive Manufacturing has allowed designing an optimized personal aircraft. Provided enough financial resources, group 12 is confident that in the very near future it will become possible to print such an aircraft. However, it might not be wise to use Additive Manufacturing for the entire aircraft, a synergy with conventional production techniques would most likely yield a better design.

Leonardo Times OCTOBER 2014

04-Dec-14 21:58:12

THE FX-15

15 RED BULL MEDIA HOUSE

FlashCo., a new player in the energy drink business, wants to launch a new product to end the dominance of Red Bull, their largest competitor. Management has set the target to beat Red Bull in its own flagship event: the Red Bull Air Race. DSE group 15 was tasked to design the FX-15: an aerobatic racing aircraft with the prime objective to win the Red Bull Air Race.

TEXT DSE group 15

MISSION The Red Bull Air Race is a competition in which the world’s best pilots fly their aircraft through a sixty second track with extreme maneuvers. These maneuvers expose the aircraft and its pilot to load factors of up to ten, pushing man and machine to the very limit. One second of inattentiveness can mean the difference between winning and losing.

The racetrack itself is constrained by pairs of vertical poles, known as air gates. Participating teams must fly their aircraft through all gates as fast as possible. Touching a gate is punished with a time penalty and flying maneuvers at a load factor in excess of ten is not permitted. Among the maneuvers flown in the Red Bull Air Race are the KnifeEdge, the high-g turn, the slalom, and the Half Cuban Eight.

The race has duration of approximately one minute. The FX-15 has to demonstrate all of its abilities in this short amount of time. Tight regulations confine the freedom of the engineering team: Red Bull demands a conventional aircraft layout and imposes a lower bound on the takeoff

weight. DSE group 15 was able to come up with an innovative aircraft design despite these strict rules.

DESIGN The FX-15 is the result of ten weeks of hard work by DSE group 15. The only way to beat the competition was to build an aircraft with a lower weight or a lower drag.

Since competing aircraft have a mass close to the allowed minimum, it became indispensable to reduce drag as much as possible to still gain an edge over the competition.

The need for low drag could be satisfied thanks to an innovative fuselage design.

The pilot is seated in the front of the aircraft between the nose and the engine, resulting in an unprecedented visibility not obstructed by the engine fairing. Mounting the engine behind the cockpit results in a fuselage with its heaviest and bulkiest components in the center section. This enables a highly smooth and streamlined fuselage shape with a very low amount of drag.

such unusual layout was no easy feat. The toughest challenge was to come up with a system to transmit the 315 horsepower of the engine safely along the cockpit to the three-bladed propeller. A system of shafts, chains, and sprockets turned out to be the lightest, simplest, and most durable solution. The engine is supplied with air for cooling and combustion through air inlets conveniently located in the wing roots.

This keeps cooling and intake drag to a minimum.

CONCLUSION The FX-15 was deliberately designed to be an innovative and out of the ordinary aircraft. The design is meant to show the world that one does not always have to adhere to proven layouts. It will easily stand out at any race it flies and will as a result create huge amounts of brand visibility for its client. The FX-15 will not only win the race; it will also wow the audience.

However, the design of a fuselage with

OCTOBER 2014 Leonardo Times

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18

DIAMOND OF DUBAI

Even though the worldwide economy did not do well in the past few years, one of the markets that kept and still keeps growing is the advertisement industry. Companies always search for new possibilities to reach their audience and want to distinguish themselves as much as possible. To fit in this desire the idea came up to make a huge balloon, able to display commercials. The target location is Dubai and the main target audience is the people at the Dubai airport, the second busiest airport in the world for international passengers with a total capacity of 80,000,000 passengers annually.

TEXT DSE group 18

UNITED BALLOON As one of few DSE projects, we had the chance to design for a real company, with a big chance to have it really built within two years if feasibility is proven. We worked for the company United Balloon (UB), consisting of five Dutch entrepreneurs of which one is an alumni of this faculty. They came up with the idea to build a huge balloon at a certain location in Dubai with large screens that will be visible from 360° and especially from Dubai airport. Because of this requirement, the screens need to be visible at 4km distance. Next to that, also a gondola for 50 persons going up and down four times an hour was requested.

It is important that the balloon is going to be located at considerable height to reach a broad audience. UB required the screens to be positioned at a height of 250m.

BRAINSTORMING The challenge of the assignment was the lack of reference designs. On the other side it was also an opportunity, since we could put all our creativity in making a design completely created by ourselves. UB al-

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ready pushed our way of thinking by saying that they think an upside down, helium filled pyramid with three sides was the best option, but because it is a DSE project, we started from scratch. A lot of options were considered, but in the end, we ended up with a design quite similar to their plan, with only the shape and the stabilization system as major differences. Because of the better aerodynamic properties and a more pleasing look, a diamond shape was chosen. We designed our logo based on this shape and renamed our project to ‘Diamond of Dubai’. UB liked the idea and immediately registered www.diamondofdubai.com, because Dubai is known as the money capital of the Middle East and a diamond in the Dubai skyline represents this image. The stability of the balloon was a major concern. It was difficult to develop a system to guarantee stability at all circumstances, especially since UB wanted to use as little ground space as possible since in Dubai that is very expensive.

FINAL DESIGN Finally, we came up with a diamond of

95m and a gondola that goes up to 200m.

With this, the top of the balloon is positioned at the same height as the top of the Eiffel tower. It is attached to twelve cables and is able to stay up at full height with a ground wind speed up to 5m/s. If the wind goes faster the balloon can stay in operation, but at a lower height up to wind speeds of 12m/s. Luckily, the climate in Dubai mostly generates slight breezes, so much uptime is expected, except for the sandstorms that occur once or twice a year in spring and last a few days. If the winds then succeed 12m/s the balloon enters his safety mode and gets anchored to the ground. To solve the problem with the ground space, six poles of 50m high are used to attach the stability cables. They keep the cables under the same angle, but make the lower part of the cable unnecessary. Since feasibility is proven, UB wants to go on with the project and plans to finalize the detailed design within this year.

The launch is planned for September 2015.

For the detailed design, UB plans to continue the collaboration with TU students, possibly in the form of internships.

Leonardo Times OCTOBER 2014

04-Dec-14 21:58:45

19

THE AEGIR CONSTELLATION

The traffic around the North Sea has grown more than 50% since 2000, which nowadays has increased to 330,000 ships per year in the Greater North Sea area alone (CNSS, 2014). This has resulted in multiple problems in this region such as illegal fishing, oil dumping and ship accidents. Monitoring with ground or air based radar systems is carried out, though these systems tend to have a small range and are therefore restricted to a small area. To improve this monitoring the Aegir constellation, a space based radar system, needs to be implemented.

DSE GROUP 19

TEXT DSE group 19

SPACECRAFT DESIGN For the design of the spacecraft, inspiration is taken from the Apollo mission: the Lunar SECRet spacecraft is composed of an orbiter, re-entry vehicle and a lander (composed of an ascent stage and descent stage). The ascent stage contains the propellant and the engines for both braking and taking off from the lunar surface.

This way no extra propellant tanks and engines are needed in the descent stage which saves propellant mass. The descent stage contains a fuel cell and a drilling system based on the ExoMars drill. The drill can sample two meter of lunar rock in parts of ten centimeters. Using a robotic arm that is fitted to the ascent stage, the samples are transferred to the cryogenic system (which is also contained in the ascents stage). The descent stage provides a three-legged platform from which the ascent stage takes off. The orbiter contains the propellant for inclination changes and the journey back to Earth. From within the crater there is no direct line of sight with Earth, so the orbiter is fitted with a communication system to communicate with Earth. In order to cope with the thermal loads an ablative heat shield was designed for the re-entry vehicle using phe-

nolic impregnated carbon ablator (PICA) which is a low density heat shield material. This ensures the temperature inside remains below operational limits of the cryogenic system.

Furthermore, the whole cryogenic system is designed such that it can be transferred from the ascent stage to the re-entry vehicle by the robotic arm contained in the ascent stage.

CRYOGENIC SYSTEM To preserve the sample in compliance with customer requirements, it needs to be stored at temperatures below 120K at all times, up to twelve hours after re-entry.

To ensure the sample remains at cryogenic temperatures a reverse-Brayton cryocooler is used. In space, the cooling liquid used by the cryogenic system rejects heat into space using radiation. However, after re-entry, whilst in the atmosphere, this is not possible. Therefore, a heat sink is used here to absorb the heat from the cooling liquid. This system allows for the extraction of large quantities of energy from the cooling liquid, without heating up notably. The thermal power input drastically increases in atmospheric conditions due to convection and conduction. An aerogel insulation layer is therefore used as thermal insulator. The cryogenic system, which is normally a closed and insulated system, is designed to be able to open up and receive samples from the robotic arm.

MISSION OVERVIEW The spacecraft is launched into a translunar injection using a Falcon Heavy launch vehicle that will be operational before 2025. Upon arrival at the Moon, the lander (composed of the ascent stage and descent stage) descends towards the Wiechert J crater on the South Pole, where the samples are retrieved. The ascent stage uses the descent stage (which is left behind on the lunar surface) as a platform to launch from the Moon. Once in orbit it will dock with the orbiter and the cryogenic system including the samples are transferred from the ascent stage to the re-entry vehicle. The orbiter will then initiate a trans-Earth injection and the ascent stage is left behind in lunar orbit. Upon arrival the orbiter is left to burn up in the atmosphere while the re-entry vehicle descends and lands safely in Kazakhstan.

The mission will have a total life-cycle cost of â‚Ź477 million.

OCTOBER 2014 Leonardo Times

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Column

DARK MATTER MYSTERY Should we be spending resources on this research?

On 24th June this year, results were published with data from NASA’s Chandra and ESA’s XMM-Newton X-ray space observatories. An odd peak was found at a specific wavelength without any accompanying peaks that would be present if the source was a known element, and it was theorised that this could be a clue to solving a the mystery of dark matter.

TEXT Bob Roos, MSc Student Aerospace Engineering, Editor Leonardo Times

THE BACKGROUND You may occasionally hear about a new discovery that may hold the truth to dark matter. But what is dark matter? The simplest answer is that we do not know what dark matter is, or whether it actually exists. A more elaborate answer is that, in most galaxies that we observe (interestingly enough our own galaxy is an exception), stars in the outer regions of those galaxies appear to be moving significantly faster than they should be, based on our present understanding of orbital mechanics. We can estimate the amount of mass inside those galaxies from, for instance, the orbital velocities of stars closer to the centre of those galaxies, and the amount of stars that we observe. As the orbital velocities seem significantly larger, extra invisible mass should be present in those galaxies, mass that we cannot see, but that is gravitationally binding those outer stars to the galaxy. This invisible mass is what we call dark matter. According to current estimations there is approximately five times more dark matter in the universe than matter that we actually are familiar with. For more elaborate background information and a good introduction to the subject of dark matter, the interested reader can refer to [Freeman, McNamara, 2006].

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THEORIES There are plenty of theories regarding the nature of dark matter; a Google Scholar search finds hundreds of papers detailing all kinds of ideas on what it could be.

Some believe that our current laws of gravity may be flawed, while others believe dark matter to be real particles, just not the particles that we are familiar with.

Some papers use observations from observatories and space telescopes to refute previous theories by other scientists, but the majority is proposing new theories.

OBSERVATORIES Astrophysicists need observations and raw data to have any real idea about which theories make sense and which theories can be discarded. These observatories can be on Earth, either by building telescopes on Earth and looking at the sky, or by simulating events experimentally in the Large Hadron Collider. The telescopes can also be in space, which avoids atmospheric distortion of the data. NASA’s Chandra and ESA’s XMM-Newton satellites mentioned in the introduction are such observatories. But the data needs to be collected over significantly more wavelengths than just X-rays, preferably over the entire electromagnetic spectrum, and to do so a legion of satellites, each specialised for a different wavelength band, needs to be in space.

COSTS AND PRIORITIES From an astronomer’s point of view, the more observatories there are in space, the more galaxies can be observed in more wavelengths, the more raw data available, the better it is. However, space observatories are costly, they need to be built with extreme precision to prevent blurry pictures, they often need extreme cooling to prevent disturbance originating as blackbody radiation from the satellite itself, and launching them to orbit is costly as well.

In times where space budgets are limited, agencies need to consider seriously about the missions they choose to invest in.

Many agencies may prioritise Earth observation satellites over space observatories, to help predict the weather for instance, or to monitor climate change. The direct benefit from looking at other galaxies is not as strikingly clear as the benefit is in other missions. However, this does not mean that research to other galaxies, including research into dark matter, should be abandoned. The main reason for researching into dark matter is to answer the simple question: ‘What is most of the matter in the universe made of?’ Physical benefits may come to future generations, similar to how the main benefit of knowing Newton’s law of gravitation, and knowing how it scales with distance, did not come until we started space travel.

Leonardo Times OCTOBER 2014

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