FIGURE 2.19 AIRPORT TERMINAL LAYERS AS PROPOSED BY EDWARDS

and design. de Neufville and Belin (2002) studied shared-use facilities to achieve flexibility in airport operations; de Neufville and Odoni (2003) studied uncertainty; de Neufville (2008) also researched on flexibility in low-cost airports; Edwards (2005) discussed shearing layers of change in terminal design, and Chambers (2007) studied how to tackle uncertainty in airport design. Sarah Shuchi (2015) studied in detail the flexibility approach in the departure area and developed a detailed method for automatic plan generation.

• de Neufville and his co-authors (2008) Richard de Neufville is probably the most diversified author of airport flexibility since he has several publications with different proposes. de Neufville and his co-authors identified several issues related to flexibility. Choosing an appropriate terminal configuration should be given initial priority to handle various types of passenger need, where “hybrid‟ design is highly encouraged (de Neufville, 1995). According to de Neufville and Odoni (2003), the primary flexibility in terminal buildings can be achieved by choosing an appropriate configuration that helps to expand and contract according to the activities performed.

• Brian Edwards (2000) Brian Edwards in his book The Modern Airport Terminal discussed the importance of flexibility in airport design. According to his point of view, the need for flexibility in airport design is the result of complex interactions between airline companies, aircraft design, and airport authorities. Airport terminals are functionally turbulent spaces; different parts of an airport change at different rates. Recognizing the separate layers, as proposed by Edwards, helps in understanding the process. Each layer is on a distinct timescale so concurrent changes in each layer tend to disrupt the whole. Recognizing separate layers and allowing some disconnection between them is necessary to allow the terminal building to renew itself.

Figure 2.19 Airport terminal layers as proposed by Edwards

• Butters (2010) Butters investigated flexibility in airport design and proposed that to adapt to the changing environment at airports, four key stages of development or refurbishment should be embedded: master planning, building design, space planning, and component design. The importance of buffer spaces was also identified; appropriate incorporation of such spaces in layout and space planning for future expansion keeps possibilities for converting spaces from non-operational functions to operational. Converting adjacent spaces from non-operational space to operational is another strategy to add flexibility in space planning.

• Gil and Tether (2011) The key contribution of their study was a theoretical understanding of the conditions under which risk management and design flexibility may complement each other to manage the pressure between efficiency and effectiveness in large projects. The balance between flexibility and risk management helps to reconcile efficiency and effectiveness.

• Liliana Magalhães and Rosário Macário (2012) They suggested that “multiairports” should also consider flexibility levels along with the four key stages defined by Butters. The framework also considers exogenous variables, such as demand, technology, regulation, and financing.

• Sarah Shuchi (2015) She proposed a design framework to develop flexible layouts of departure areas in an international airport. She developed a flexible design framework for airport terminals based on several hypotheses extracted from the literature. She generated an algorithm demonstrating the applicability of the proposed design concept by obtaining spatial layout for preliminary design based on passenger activity. She also set a framework for design parameters.

• Catarina Além (2015) She has studied the various levels of flexibility and flexibility options available. She has studied the advantages and disadvantages of the same and carried out an analysis of various flexible airports. And has shown a comparative analysis of the same.

Table 2.4 Evaluation of the flexibility options (Alem, 2015)

2.5 FLEXIBILITY: AN OPTION OR A NECESSITY?

Through the literature review, it was possible to notice that two exogenous variables are crucial for airport flexibility: demand and investment. It is demand fluctuations and investment constraints that motivate flexibility in the first place. It is possible to say that flexibility exists to provide the airport with the ability to face demand changes without jeopardizing investment(Magalhães, Reis, & Macário, 2012). Certainly, other exogenous variables influence flexibility, or instance regulation aspects and technology advances.

A typical holdroom has linearly arranged seats with a monotonous environment making the passengers feel more anxious and uncomfortable before boarding their flight. Be it an elderly or a kid the seating arrangement is the same for every user. Since the beginning, the design of the holdrooms has not evolved much. On the contrary, holdrooms are supposed to be a place where the passengers can relax after the tiresome journey through the airport processes.

With the new developments in airports and evolving preferences of passengers, operators of the executive lounges have brought lounges in the reach of economy class passengers who can use these services for a nominal fee. Through this, they have tried to reach out to more people. Hence, unlike earlier, they are now open to everyday leisure travelers who can enjoy the benefits of an airport lounge experience. This step made more people eligible for access turning

these once-calm spaces into spaces that are just as crowded as the terminal and do not maintain its luxury standards. There are now kids running all over the place making noise, people hauling over buffet and drinks and the entire of the entire place is lost. This step sure does reduce the load on the holdrooms but it compromises the decorum of the executive lounges.

With continuous advancements, new types, sizes, and patterns of aircraft are being introduced more frequently. It is the terminal that has to adapt and accommodate it. New, larger aircraft impose changes on the capacity of departure lounges demanding more service and space requirements.

The growth of the city the airport is located in is directly proportional to the traffic it calls at its airport. With the city developing it calls for the expansion of the terminals and the need for upgradation. To a certain extent, flexibility can be an effective option, but then after expansion becomes a necessity.

This kind of uncertain decision and changes result in fluctuating demand of the spaces, in some cases, there would be access to leftover spaces while in some there would be insufficient spaces. Thus, it becomes important to adapt to these changes in the long run or short run.

3 SIGNIFICANCE OF FORM

Designers and planners have been trying on achieving architectural marvels in the field of airport design. In doing so they have to make sure that passenger comfort is not compromised. The two types of passengers: business travelers and leisure travelers and significant variations in the characteristics and ratio of these two passenger types can influence terminal space requirements and staffing.

This section describes the basic configuration of airport passenger buildings concerning the passenger movement and how it affects the holdroom designs. The subsequent section analyzes the performance of the waiting areas as per the building configuration and the characteristic of the passenger.