SPECIAL REPORT
Improving Runway Safety
Surface Preparation Technologies for Airports in the 21st Century Why Airports Must Focus on the Condition of Runways The Evolution of Surface Preparation Why New Surface Preparation Technologies Represent a Major Step Forward How to Choose the Best Surface Preparation
Sponsored by
Published by Global Business Media
IMPROVING RUNWAY SAFETY
SPECIAL REPORT
Improving Runway Safety
Surface Preparation Technologies for Airports in the 21st Century
Contents
Why Airports Must Focus on the Condition of Runways The Evolution of Surface Preparation Why New Surface Preparation Technologies Represent a Major Step Forward How to Choose the Best Surface Preparation
Foreword
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Tom Cropper, Editor
Surface Preparation Technologies for 3 Airports in the 21st Century Blastrac Global Sponsored by
Published by Global Business Media
Published by Global Business Media Global Business Media Limited 62 The Street Ashtead Surrey KT21 1AT United Kingdom
Friction Improvements Gate Area Surface Cleaning Thermo-Plastic Line Removal Gate Area Line Removal General Concrete Maintenance Decorative Surfaces
Switchboard: +44 (0)1737 850 939 Fax: +44 (0)1737 851 952 Email: info@globalbusinessmedia.org Website: www.globalbusinessmedia.org
Why Airports Must Focus on 7 the Condition of Runways
Publisher Kevin Bell
Paying the Price Crowded Skies The Importance of Maintenance Technologies for the Next Generation
Business Development Director Marie-Anne Brooks Editor Tom Cropper Senior Project Manager Steve Banks Advertising Executives Michael McCarthy Abigail Coombes Production Manager Paul Davies For further information visit: www.globalbusinessmedia.org The opinions and views expressed in the editorial content in this publication are those of the authors alone and do not necessarily represent the views of any organisation with which they may be associated. Material in advertisements and promotional features may be considered to represent the views of the advertisers and promoters. The views and opinions expressed in this publication do not necessarily express the views of the Publishers or the Editor. While every care has been taken in the preparation of this publication, neither the Publishers nor the Editor are responsible for such opinions and views or for any inaccuracies in the articles.
Š 2019. The entire contents of this publication are protected by copyright. Full details are available from the Publishers. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical photocopying, recording or otherwise, without the prior permission of the copyright owner.
Tom Cropper, Editor
The Evolution of Surface Preparation 9 Jo Roth, Staff Writer
Measuring Surface Grip Improving Surface Grip The New Generation
Why New Surface Preparation Technologies Represent a Major Step Forward
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James Butler, Staff Writer
Runway Conditions More Sustainable Options Shot Blasting Making a Buying Choice
How to Choose the Best Surface Preparation
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Tom Cropper, Editor
Testing and Monitoring Assessing the Cost Airport Location Choosing a Provider
References 15
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IMPROVING RUNWAY SAFETY
Foreword A
S AN aircraft comes into land, the pilot is putting his faith in many things, not least of which is the condition of the runway. If the surface is below par, slippery, damaged or contaminated the pilot and all his passengers will be at risk. However, maintenance is more than just a safety issue. Good surface preparation can extend the lifecycle of runways, reducing the need to schedule major resurfacing work which results in downtime. Our opening article comes from one of the world’s leading producers of surface preparation technologies, Blastrac Global, who look at the different methods of surface maintenance and how they should be applied across the airfield. Airports, they say, should develop a comprehensive toolkit of solutions to cater to the demands of each individual area. We then look at some of the challenges confronting
profit margins tighter. They will need to update their preparation strategies to keep pace with the developing market. Jo Roth then looks at the evolution of the sector and how modern technologies such as shot blasting and ultra-high-pressure water cleaning offer a major step forward over and above old fashioned chemical treatments. James Butler then examines what the latest technologies such as state-of-the-art shot blasting can offer when compared with other options. There is no single approach and the best solution will depend on the size of the airport, its location and the climate. Finally, we’ll examine all the factors operators should take into consideration from inspection conditions to choosing the best method and the provider.
airport operators in the modern age. They will have to deal with a future in which traffic is becoming heavier, the life expectancy of runways shorter and
Tom Cropper Editor
Tom Cropper has produced articles and reports on various aspects of global business over the past 15 years. He has also worked as a copywriter for some of the largest corporations in the world, including ING, KPMG and the World Wildlife Fund.
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Surface Preparation Technologies for Airports in the 21st Century Blastrac Global The future of airport surfaces maintenance is the adoption of a “Tool Box” approach to the various scope of work necessary at today’s airports. Managers and maintenance crews will need a variety of equipment to keep pavement surfaces in the safest and best conditions to meet the demanding standards of the 21st Century.
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LASTRAC IS the leading global developer and manufacturer of surface preparation equipment. We have an extensive range with over 55 different machines for preparing and maintaining floors and other surfaces for all kinds of materials. Our innovative techniques are developed in-house and on demand by our strong R&D department. Blastrac surface preparation equipment can be used on airfields for: • Gate cleaning • Removal or cleaning lines • Removal of excessive rubber from runways • Improvement of grip by increasing the surface friction • Improvement of light reflection • Reduction of vibrations and noise levels during take off and landing • Decorative indoor and outdoor surfaces
Friction Improvements The condition of the runway surface is important when you are looking to improve airfield safety. There are many elements which can affect this such as: structure, materials used, surface type, snow, ice, water and contamination from various sources (especially from rubber deposits). Regardless of the pavement type, runway friction characteristics will change over time depending on the type and frequency of aircraft activity and weather conditions. In addition to ordinary mechanical wear and tear from aircraft tires, contaminants can collect on runway pavement surfaces which decreases their friction properties. Accidents and near accidents can occur from planes overshooting or veering off contaminated runways. It is therefore essential to maintain the airport runways to the highest possible standards and to ensure adequate surface drainage and
grip, especially in areas of take off and landing. Companies continue to develop technologies in order to reduce the braking distance of airplanes. Over the years they have developed different technologies and methods such as new braking mechanisms and methods to prevent the build up of snow, ice, water and contaminants on the runway. Retexturing the surface by applying Ultra-HighPressure blasting or shot blasting technology has been repeatedly demonstrated to be an important key for successful friction improvements. Rubber Removal As aircraft landings take place, the traffic wears down macro-texture and micro-texture as contaminants build up on the runway pavement. This build up of rubber will decrease water drainage and friction to the point where safety may be diminished. Removal of excessive rubber from the runway is needed to maintain safe operations; rubber should be removed based on the following FAA schedule. A very efficient and cost-effective method for removing rubber deposits from a runway or new surfaces which have a coating of bitumen binder over the aggregate particles is Ultra-HighPressure Water. Because pavement quality varies, Rubber Deposit Removal Frequency Aircraft Landings per day
Rubber Removal Frequency
Less Than 15 16 to 30 31 to 90 91 to 150 151 to 210 Greater than 210
2 Years 1 Year 6 Months 4 Months 3 Months 2 Months
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Regardless of the pavement type, runway friction characteristics will change over time depending on the type and frequency of aircraft activity and weather conditions
Application
Technology Equipment
Rubber Removal UHP Water blasting 4006AC Shot blasting 4006ST 4006HT 2-45DTM with shotblast attachment Macro-Texturing UHP Water blasting 4006AC Shot blasting 4006ST 4006HT 2-45DTM with shotblast attachment Micro-Texturing Shot blasting 2-45DTM with shotblast or Grinding attachment Gate Area Surface Cleaning HP Water CY5500 Thermo-Plastic Line Removal UHP Water blasting 4006AC Grinding 4006ST 4006HT Gate Area Line Removal UHP Water blasting Single Disc Grinding Shot blasting
Grinding with bush hammer tool 4006AC with CY200 Attachment 4006ST with CY200 Attachment 4006HT with CY200 Attachment Grinding with bush hammer tool Full line of shot blasting machines
General Concrete Maintenance Grinding Full line of single disc grinders Scarifying Full line of triple disc planetary grinders Shot blasting Full line of scarifying machines Milling Full line of shot blasting machines BMP4000 Decorative surfaces
Grinding HP Water Cleaning
equipment that enables variable pressure settings should be selected to avoid surface damage. Machine productivity (rubber removal square meters per hour) is another important consideration. In cases where temperatures are below freezing or fresh water supply is an issue, shot blasting should be used for rubber removal. Chemical removal of rubber deposits is also widely used, but environmental contamination concerns are eliminating this method. Both Ultra-High-Pressure Water and shot blasting are very cost effective, environmentally friendly and high-performance technologies
SHOT BLASTING
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Full line of triple disc planetary grinders CY5500, TR5500
for reducing the danger of slippery runways. They will remove rubber deposits and will bring the surface Macro texture back to that of the aggregates ability. In some cases when friction recovery maintenance has been neglected, macro-texturing can only be accomplished with shot blasting. Shot blasting is the only technology that will restore Micro-Texture values to pavement surfaces. Improvement of Micro texture with the shot blasting process is extremely effective. It will in all cases bring back the full benefit of the PSV of the aggregate as per its original properties.
ULTRA-HIGH-PRESSURE WATER
IMPROVING RUNWAY SAFETY
Macro-Texturing
MACROTEXTURE is the space or voids between the aggregate particles. The texture depth / macro texture of an asphalt pavement surface will normally be between 1.0mm to 1.5mms. It is this macrotexture which allows the water to drain away from the surface and greatly contributes to skid resistance in wet conditions.
Micro-Texturing Microtexture is the fine component of surface texture formed by the tiny interstices on the surface of the aggregate particles. It is the main contributor to providing grip or skid resistance with the tyre, particularly at low speeds. Microtexture is measured by PSV using the British Pendulum Tester or by mobile methods such as the Griptester or SCRIM.
Friction Testing The following chart indicates friction survey frequency. Minimum Friction Survey Frequency Aircraft Landings per day
Friction Survey Frequency
Less Than 15 16 to 30 31 to 90 91 to 150 151 to 210 Greater than 210
1 Year 6 Months 3 Months 1 Month 2 Weeks 1 Week
HIGH PRESSURE WATER CLEANING
Gate Area Surface Cleaning Chemical spills and general contamination of gate areas is a problem that needs to be addressed for safety and aesthetics concerns. High pressure water cleaning devices (1600 to 5500 PSI) are most frequently used. Ride on units with recovery/ reclaim systems are the most efficient because they eliminate the need to collect waste and waste water using vacuums and labour. To avoid removing and replacing expensive line material, the same technology can be used for cleaning the line markings. Especially for smaller areas, or when ingress/egress to the area is restricted, a walk behind attachment can be connected to the high pressure water vehicle.
WALK BEHIND ATTACHMENT
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Chemical spills and general contamination of gate areas is a problem that needs to be addressed for safety and aesthetics concerns
ULTRA-HIGH PRESSURE WATER
GRINDING WITH BUSH HAMMER
Thermo-Plastic Line Removal
maintenance projects. Paired with approved (HEPA) dust collectors, these machines eliminate clean up and protect airport employees from airborne contaminants.
Ultra-High-Pressure Water has proven to be the most cost-effective approach for thermoplastic line removal. Grinding with a bush hammer tool will also work for the smaller or more remote areas. Scarifying is only being used on a much smaller scale because of the concern for long term surface damage and structural fracturing to the pavement base. Due to environmental issues and extensive clean-up and disposal, sandblasting is no longer an option that is being used.
Decorative Surfaces
Gate Area Line Removal
BUSH HAMMERED CONCRETE
GRINDING WITH BUSH HAMMER
Ultra-High-Pressure Water is extremely suitable, but when ingress/egress to the area is restricted, using a CY200 walk behind head or a single disc grinding with a bush hammer tool or mobile walk behind shotblaster are the best options.
Polished surfaces are being treated with progressively finer grinding tools. Depending on the basic material (concrete, asphalt, terrazzo, marble, natural stone) and color, the different depth you polish to, texture and depth of your aggregates, you can create any result with a perfect shiny finish. Polished surface floors are low-maintenance, as they are more durable and easier to clean than many flooring options. For outside areas, bush-hammering is a process which enables you to achieve a similar effect as natural cut stone, with a concrete surface as basis. Bush-hammered concrete is the ideal solution to have a natural effect less smooth than polished concrete, less rough than brushed or blasted concrete and less decorative than stamped concrete. High Pressure Water Machines are great for general cleaning of these surfaces.
WALK BEHIND SHOTBLASTER
General Concrete Maintenance Wherever there are pavement or concrete surfaces, there are general maintenance requirements. Portable shotblasters, grinders, scarifiers and milling machines are great tools to have on hand for accomplishing these 6 | WWW.AIRPORTTECHNOLOGYREPORTS.COM
POLISHED CONCRETE
IMPROVING RUNWAY SAFETY
Why Airports Must Focus on the Condition of Runways Tom Cropper, Editor As Airports face challenges of finance and capacity, runway maintenance is becoming more important than ever.
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T’S APRIL 2017, and 300 flights are cancelled as Beijing Airport shuts its runway for essential repairs. For four long weeks, passengers were forced to contend with longer waiting times, taxiing and other delays as the airport carried out maintenance. In the meantime, the airport suffers with revenue loss and spiralling costs together with all the logistical challenges associated with trying to process the same number of passengers with a reduced runway capacity. This is just one example of the challenges caused by downtime, and why maintaining the surface of a runway is essential in handling the increased maintenance requirements of the future1.
Paying the Price From a purely financial point of view, the impact on Beijing Airport over the course of the shutdown was significant. It saw an estimated reduction in the number of passengers passing through the terminal of around 10 to 15%. However, they say airlines helped to offset this with bigger aircraft and increasing their own capacity. Even so, in an environment in which airports are increasingly finding it difficult to operate at a profit, the costs of downtime can become a serious drain on resources. A report from ACI shows that the majority of the world’s Airports, except for the larger international hubs, are operating at a loss2. Even those which are making a profit need to manage costs. Future market movements such as the price of aviation fuel and the future direction of ticket prices may place profits under jeopardy. Airports deploy a range of strategies to maximise profits and are increasingly turning to non-airside related activities, such as retail, to boost their own financial performance. However, the potential is limited, so they will need to streamline processes and reduce unnecessary expense where they can.
Crowded Skies It is the strain on infrastructure and capacity limits, though, that may exercise the minds of many operators. IATA’s long-term forecast predicts air
traffic to double over the next 20 years. By 2035 they expect there to be more than 7 billion people travelling by air with emerging markets such as China showing particularly rapid growth3. As we move into a busier future, more airports will be operating at, or beyond, capacity for longer. The strain is already being felt, with a report into punctuality suggesting that overcrowding is already having an impact. At Heathrow, a quarter of all departures left outside their original take-off slot4. Capacity for expansion is limited. Planning new runways is controversial, expensive and can take years. Heathrow’s Terminal 5 was more than 20 years in development from initial concepts to its opening, and plans for a new runway face stiff opposition from local residents and campaign groups. Existing infrastructure will have to stretch its capacity, which means there is less margin for error, a lower tolerance of downtime and runways will be expected to manage high traffic loads and greater wear and tear. Airports will also have to keep note of a changing regulatory environment which continually raises the bar for standards of safety and performance as well as more stringent environmental requirements. Techniques such as chemical cleansing will inevitably represent a danger to plant and wildlife around the airport itself. Airports are moving to less toxic options which pose lower environmental risk.
The Importance of Maintenance The challenges are growing, but it’s far from certain that all airports are keeping pace. Although most understand the importance of maintenance, the rise of new technologies, plus the challenges of modern aviation mean they are not always optimising their maintenance procedures. As a result, passenger safety suffers, and so too do profit margins. It’s easy to view such downtime as being an inevitable consequence of busy traffic at modern airports, but that needn’t be the case. At Glasgow Airport, for example, a major operation succeeded in completely resurfacing the main runway without any disruption to WWW.AIRPORTTECHNOLOGYREPORTS.COM | 7
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Manufacturers are continually developing more effective technology and machinery to improve airfield maintenance. Their aim is to enhance grip, extend the life of a surface, and reduce the need for urgent repair
services by laying a new surface in stages over the course of the night. It involved a major logistical operation including an army of more than 200 workers, three years of planning and a new form of asphalt to prepare the surface for decades to come5. Elsewhere, the situation is less promising, especially in developing countries. Reports circulated earlier this year suggested that airports runways under the management of the FAAN in Nigeria are poorly maintained. Problems with facilities and surfaces were causing damage to aircraft, incurring additional costs and impacting safety6.
Technologies for the Next Generation Manufacturers are continually developing more effective technology and machinery to improve airfield maintenance. Their aim is to enhance grip, extend the life of a surface, and reduce the need for urgent repair. By rethinking maintenance strategies and processes, airports can find potentially enormous savings and keep themselves operating at maximum capacity for much longer.
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To do this they will need to update maintenance processes and equipment to ensure runway surfaces are maintained to the highest possible standard without the need for shutting down facilities or interrupting operations. Prevention, as they say, is better than cure and operators now have an arsenal of options at their disposal. Chemical cleaning companies are refining their approach and introducing biodegradable and environmentally friendly options, while ultra-high-pressure water blasting and shot blasting technologies are developing quickly and delivering higher levels of cleaning with minimal environmental impact. They can’t eliminate problems or retard the aging process entirely, but they can maintain higher levels of grip for longer, make it easier to carry out essential surface maintenance and reduce the risk of an emergency intervention, which could inflict costly delays. By understanding the changing nature of the challenge and the solutions available, operators can ensure their maintenance technologies are fighting fit for the next era of aviation.
IMPROVING RUNWAY SAFETY
The Evolution of Surface Preparation Jo Roth, Staff Writer New technologies and processes are coming to the market which provide airports with a fresh toolbox to improve surface conditions.
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HE AVERAGE aircraft will be coming in to land at between 260-280 kmph. When they do, they are entering one of the most dangerous phases of the journey. An aircraft is a bit like a swan – serene and graceful in the air, but unstable and clumsy when it hits the land. While car drivers can slow down to adjust for bad weather conditions or surfaces, pilots don’t have that luxury, so, as they approach that runway, they are relying on a dependable standard of grip and skid resistance. Unfortunately, that’s not something that can always be taken for granted. Different countries have different approaches. Some mandate minimum standards, while others simply issue much less binding guidance notices. In some remote areas, the surface of the runway is neglected entirely, which creates a serious safety issue for pilots and greatly restricts the times when an airport can be operative. In a world in which time is money, surface preparation is not only an issue of safety, it’s important for the financial viability of the entire operation. Technology is developing. Airports and governments are adjusting their focus on surface preparation and companies are delivering more products and equipment. Choosing the correct toolbox will be crucial in establishing an effective strategy.
Measuring Surface Grip As soon as a runway enters active service, its performance will inevitably start to degrade. Daily use deposits contaminants such as rubber and other dirt which affect the micro and macro texture, reducing the friction and stopping distance. The results can be seen in damage to aircraft, near misses and, in some cases, overshoots. One of the more extreme examples was caught on camera in 2016 when a Cargo plane overshot the runway at Bergamo when landing from Paris7, crashed through a dual carriageway and into another road. There can, of course, be many reasons for overshoots. It could be down to bad weather, a long landing, a tailwind or an
excessively high approach contributing to a landing speed which is too fast. But it can also be down to the condition of the runway. What’s worse, it’s an issue many airports may not be aware of, so one of the more important advances in recent years has been in measuring the friction and skid resistance of a runway. Skid resistance relies on several factors: •M icrotexture: The microtexture is the fine roughness you can feel by touch. Ideally it should feel a little like sand paper. This influences skid resistance at speeds below 60kmph. •M acrotexture: is created by visible texture depth. It channels water away from the tyres and distorts the rubber to improve stopping power. •D ryness: If a surface is wet it can lead to aquaplaning which occurs when a layer of water gets between the rubber and the surface. Regular monitoring and inspection allow airports to maintain runways in the best possible condition.
Improving Surface Grip The development of new types of asphalts and measures like grooving have the potential to improve the skid resistance of runways. Sawing grooves into the surface increases the friction and the amount of water channelled away from impact. Grooving incurs an associated cost, and some airports are turning to un-grooved asphalt as a way of reducing downtime during relaying. Manchester Airport, for example, used an ungrooved BBA mixture from France. Its surface characteristics supposedly negate the need for grooving and bring other benefits. It is ready for trafficking as soon as the surface has been laid and cooled. Aircraft can also land on a surface which is ‘exposed’ and laid without any additional surface treatment8. Airports also have gains to make in using more advanced surface preparation techniques. Methods such as shot blasting offer an environmentally friendly, non-destructive way to deliver much improved surface cleaning, which not only slows the deterioration of the surface, but can return it to its original micro and macro WWW.AIRPORTTECHNOLOGYREPORTS.COM | 9
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Blastrac also provides training from their sales offices around the world to make it easier for buyers to integrate their equipment into existing practices
texture profile. These represent the gaps between the aggregates and the particles and play a vital role in maintaining surface friction. These degrade as rubber and other debris becomes lodged in the gaps. Shot blasting penetrates deeper and gives a fuller clearance to restore macrotexture and grip.
The New Generation One of the leading names in this space is Blastrac, which has a number of options depending on the area to be cleared. Walk behind models have a lower profile and are useful for smaller spaces which may need tight corners. Larger models, meanwhile, come fitted within a truck and dramatically increase the surface preparation speed. The 2-30DTM can clean 800 square metres per hour9 while the biggest is the 2-45DTM which prepares up to 3,000 square metres per hour10. This equipment has been specially designed to cater to the demands of modern aviation maintenance. Compact, with all equipment 10 | WWW.AIRPORTTECHNOLOGYREPORTS.COM
contained within the one vehicle, they can be deployed quickly and perform a variety of tasks around the airport. Blastrac also provides training from their sales offices around the world to make it easier for buyers to integrate their equipment into existing practices. New UHP Waterblasting machines also feature enhanced capabilities. The Cyclone 4006 series Ultra High Water Blasters can operate using 40% less water and 20% longer runtimes. They also feature variable pressure settings so any type of surface material can be blasted safely. This is, then, an example of where technology is going. It is aiming to deliver greater convenience and flexibility together with a higher performance rating and superior cost efficiency. By making it easier to maintain the traction quality of a runway surface for long periods, it is saving money across the operation and, most importantly of all, ensuring that airports are as safe as they possibly can be.
IMPROVING RUNWAY SAFETY
Why New Surface Preparation Technologies Represent a Major Step Forward James Butler, Staff Writer Next generation surface preparation technologies promise a brighter and more grippier future for runways.
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S AIRPORT operators look ahead into an uncertain future, they must ask themselves a number of searching questions: how will they cope with the more than 7billion passengers expected by 2035? How can they manage increasingly crowded skies and how can they do all this while remaining profitable, safe and meeting more demanding environmental standards?
Runway Conditions One area which is often overlooked is the impact on runways. Every aircraft which lands reduces the effectiveness of the runway by depositing rubber and other debris. As traffic increases and tyre manufacturers produce more advanced compounds designed to offer superior levels of traction, that deterioration accelerates, the life-span of the surface reduces and the cost of maintenance spirals. To ensure runways can cope with the expected surge in use, while protecting their bank balances, airports will have to develop a new generation of surface preparation and maintenance systems to enhance friction, lengthen the life expectancy of a runway and reduce the need for expensive and timeconsuming resurfacing. To cope with the challenges of the future, airports will have to rethink their approach to surface preparation and replace traditional methods with more advanced, cost effective and reliable options. Traditionally, many airports have relied on chemical treatment of surfaces. The chemicals break down rubber and make it easier to remove, but they have a problem. The most obvious is the impact on the environment. At a time when airports are under pressure to manage their effect on the surrounding environment, it is difficult to justify spreading potentially harmful chemicals on the runway.
Manufacturers have responded and produced more environmentally friendly biodegradable products to minimise the impact, but the quality is not always reliable and they still have an impact on the surface. Depending on the type of chemical and conditions, the surface may well need preparation and treatment, such as flushing to bring the temperature to the level recommended by the chemical manufacturer. The application requires a specially designed truck or trailer and the chemicals will need to be brushed in and then rinsed to remove the chemical and any loosened rubber. The process can be time-consuming and, inevitably, more expensive.
More Sustainable Options More environmentally friendly options such as high-pressure water blasting involve no chemical contamination of the surface or the surrounding area. It also does not have a structural impact on the surface and can clean grooves more deeply. Brushing cannot reach deep into the bottom of the grooves, so even if the rubber has been broken down, it will not be removed. The brushing can also polish the surface, which further reduces its skid resistance. Performance is rising as manufacturers perfect the technology. The latest devices can achieve levels of 35,000psi and more. This avoids the release of harmful chemicals into the environment. It can be used for a range of tasks such as rubber removal, cleaning up oil spills, cleaning apron and maintenance areas and line and marking removal. Compared to chemical treatment, the costs are significantly lower. There is less need for specialist personnel and equipment to manage the clean-up. The process is faster and involves less interruption to existing processes. WWW.AIRPORTTECHNOLOGYREPORTS.COM | 11
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Before buying shotblasting equipment, operators must ensure that they have the right type of blasting media and have trained staff who understand how it should be applied in order to achieve the best possible results
Shot Blasting Even so, water blasting is limited and, for a more thorough approach, many airports consider shotblasting as an additional technology for improving skid resistance. Shot blasting is one of the most effective techniques, but is not without its complications. It is an effective way to remove debris such as rubber deposits and to improve the micro and macro textures of the surface. It blasts the surface with balls or grit to remove contaminants before sucking up both the shot and the dirt. The size and make-up of the ball will vary depending on the model and the job in hand. Shot blasting can use a number of different elements on a surface including: •S teel grit: Ideal for cleaning and removing contaminants from a steel surface. •S teel shots: Small balls of steel with a diameter of 1 to 6mm can be fired at high speed against the surface. Larger ones produce a rougher finish while smaller ones produce something smoother. •C hilled iron grit: An abrasive material used for general blast cleaning such as removing oxides or paints. It is aggressive and not suitable for softer materials. This method doesn’t need potentially harmful chemicals and leaves no deposits which represent a potential hazard to the environment. Water blasting may not contaminate the surface, but it still requires a water supply. Shot blasting, on the other hand, continually recycles the shot. It
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bombards the surface; shot and loosened debris is then sucked up and separated before the shot is used again. The blast accuracy is superior and it can penetrate deep into the grooves returning the surface to its original Macro- and Micro texture. By doing so it can rejuvenate the runway, maintain optimal levels of grip and skid resistance and also extend its overall life expectancy. Like water blasting, it is theoretically nondestructive although reports have suggested older products which are not specifically designed for airport applications can damage the grooves of runways, especially when not used in the right way.
Making a Buying Choice Before buying shot-blasting equipment, operators must ensure that they have the right type of blasting media and have trained staff who understand how it should be applied in order to achieve the best possible results. When used correctly, the latest generation of technologies should be more effective and less structurally invasive than alternatives. They can save money in the long term and help airports keep runways in the best possible condition for longer while also minimising the amount of downtime. From a safety, logistical and financial point of view, they will play an important role in the health and viability of airports for many years to come.
IMPROVING RUNWAY SAFETY
How to Choose the Best Surface Preparation Tom Cropper, Editor Maintaining the grip and condition of a runway is crucial to aircraft safety, but in a shifting marketplace, how do airports decide on the best strategy for them?
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HE AVIATION industry is developing rapidly and manufacturers continually bring new and updated technologies to market. While this does bring a host of opportunities, it can also be challenging to decide on the best option. The choice isn’t made any easier by the fact that this will not be a one-size fits all approach. Airports differ in size, location and traffic volumes which means each one will have to develop its own approach.
Testing and Monitoring Any strategy must start with testing and monitoring. Each aircraft which lands deposits rubber onto the tarmac. With thousands of aircraft taking off and landing at the world’s busiest airports each year that quickly builds up, so airports must maintain a rigorous testing procedure. The FAA Friction Survey Frequency Table11 suggests tests ranging from once a year for runways with less than 15 daily landings, to once a week with those which have more than 210 landings a day. Operators can analyse their own traffic loads and decide on the best schedule for regular tests. Measuring braking performance and the friction between tyres and tarmac also help to give daily readings. Depending on the weather conditions, this can be complicated. If it’s cold or raining a measurement taken at one time may not be accurate thirty seconds later. Friction measurement practices have evolved enormously since the days when pilots reported by rating braking distance as good, or poor. The latest can draw on the total deceleration during the braking run, taking into account factors such as speed, aerodynamic drag and reverse engine thrust to deliver a more accurate figure. By giving pilots access to this data they will know if conditions are more slippery than normal and can make adjustments. Airport operators will also know if a runway has to be closed while contaminants are removed.
Assessing the Cost As with any new equipment, purchasing decisions involve balancing costs versus rewards. Ensuring an airport is equipped with the latest toolbox of surface preparation technologies will represent a significant financial outlay. Against that, the airport must consider the safety of incoming and departing aircraft, as well as how much improving their surface maintenance can save them. The big advantage of next generation technologies is their ability to manage surface maintenance projects more quickly without the need to close a runway or reduce operations. Effective ongoing maintenance will return the runway surface to its original level of skid resistance, pushing up the life expectancy of the tarmac. Each of these factors will have a commercial value to an airport, so operators will have to assess how much it would cost to close a runway, how badly it would inconvenience the passengers and affect future business and how much would a resurfacing project would cost? Assessing this impact is far from straightforward. As well as the basic price of material, labour and other equipment, airports would have to factor in the lost business through delayed or cancelled flights, the impact on passenger happiness, and wider economic implications of a closure. The cost of using maintenance equipment would, therefore, be a tiny fraction of relaying the surface. One manufacture estimates this at being a 20th of the cost of resurfacing. It is, of course, worth noting that the life-cycle of a runway cannot be prolonged indefinitely, but by extending it, the airport will make a considerable saving in the long term.
Airport Location Each airport has its own characteristics, requirements and challenges. Depending on its location, runway surfaces may experience different levels of wear and tear. An airport located close to the ocean, for example, might experience
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New equipment will require new skills within the existing workforce or hiring new people with the ability to work it
additional corrosion due to salt content in the air and in water. An airport located in the desert, meanwhile, would have to guard against the incursion of sand onto the runway. Different areas of the airport will also require a slightly different approach. Decorative areas, for example, will need a solution which can deliver a more polished finish. When using options such as shot blasting, the diameter and the composition of the cleaning medium will be crucial. Too large and it may not be able to clear narrow grooves in the runway, and may also damage the surface which may lead to irreversible loss of skid resistance. Materials can vary from sand to steel ball bearings depending on the intensity of the cleaning process.
Choosing a Provider The market is growing as producers compete to deliver next generation equipment, which means choosing between them can be difficult. Product testing is often carried out in ideal controlled conditions which can produce unrealistic results. Equipment which can demonstrate real-world performance, and a more
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rigorous and realistic testing regime will be at an advantage. Buyers must also look at those which have experience and a positive track record in the sector. In addition, they will need providers who can offer ongoing support services such as training. New equipment will require new skills within the existing workforce or hiring new people with the ability to work it. This, in itself, will represent an additional cost and undertaking which is why many of the latest machines are being designed to be as accessible and easy to use as possible, with minimal training required. Manufacturers may also provide training for staff, so that it’s easy to develop a pool of skilled individuals with the ability to use the equipment in the right way, and to train others. The trend with the latest products is to move towards options which are easy to use with minimal expertise. They are designed to be flexible and to minimise the logistics involved to drive down the manpower and cost of each operation as much as possible. Devices make the promise of being able to handle multiple tasks which also helps to reduce the number of different machines an airport needs to purchase.
IMPROVING RUNWAY SAFETY
References: 1
300 Flights Axed as Beijing Shuts Airport Runway:
http://www.scmp.com/news/china/policies-politics/article/2081490/beijing-airport-repairs-hit-tourism-airline-business The Bulk of World’s Airports Still Operating at a Loss:
2
http://www.airport-world.com/news/general-news/3774-the-bulk-of-the-world-s-airports-still-operating-at-loss-new-aci-economics-report
3
IATA Long Term Passenger Forecast: http://www.iata.org/pressroom/pr/Pages/2016-10-18-02.aspx
4
Capacity Crisis at UK Airports Revealed by Delays:
http://www.telegraph.co.uk/finance/newsbysector/industry/12085660/Capacity-crisis-at-UK-airports-revealed-by-delays-league.html
5
Runway at Glasgow Airport Replaced as Scotland Slept: http://www.bbc.co.uk/news/uk-scotland-glasgow-west-39249086
6
Poor Airport Runway Conditions: https://www.pressreader.com/nigeria/thisday/20170331/281711204489795
7
Incredible Escape as Plane Overshoots Runway:
8
http://www.dailyrecord.co.uk/news/uk-world-news/incredible-escape-plane-overshoots-runway-8565660 Ungrooved Surface at Manchester Airport: https://www.researchgate.net/publication/288824181_French_Airfield_Asphalt_Concrete_at_Manchester_Airport
9
Blastrac 2-30 DTM: https://www.blastrac.eu/230dtm-shot-blaster.html#0
10
Blastrac 2-45DTM: https://www.blastrac.eu/245dtm-shot-blaster.html#0
11
FAA Friction Frequency Survey Table: https://www.faa.gov/documentLibrary/media/Advisory_Circular/draft-150-5320-12d.pdf
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IMPROVING RUNWAY SAFETY
Notes:
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Connecting future airports! 22nd International Exhibition for Airport Equipment, Technology, Design & Services
8 – 11 OCTOBER 2019 Munich Trade Fair Centre, Germany Organisers:
www.interairport.com/europe