As the concept of hub airports has developed and the nature of competition between them increased, we have seen a global trend in airport design in recent years towards the development of progressively larger and larger terminals. But, does bigger really mean better?
The drive to develop larger terminals has been prompted by the increasing need to improve operational efficiency and flexibility, improve passenger experience, and maximise revenue generation through concentrated, centralised commercial and retail offerings.
In many instances, airport terminals have also become a destination in their own right and a status symbol through which to impress visitors arriving into the country.
This is especially true when we look to locations such as the Middle East, home to some of the largest terminals in the world. From Dubai Terminal 3 to new facilities being built or about to open in Jeddah and Doha respectively, size is everything and each new development competes for the grandest space.
If we look at how IATA’s Level of Service (LoS) rating judges a terminal’s performance, it focuses on two determinants, ‘space per passenger’ and ‘passenger process times’, which also translate into space.
Under these criteria, it could be deduced that larger terminals provide more space per passenger, meaning higher LoS and therefore greater passenger satisfaction. Certainly, some of the largest terminals around the globe consistently score highly in passenger satisfaction scores and are at the heart of very successful airports.
Conversely however, if we look at the terminals which are rated the best in ACI’s annual Airport Service Quality (ASQ) survey, they include Incheon and Singapore Changi’s T3, which although not small, are nearly three times smaller than their Middle Eastern cousins.
While big doesn’t necessarily mean bad, it cannot be proven that bigger equals better. Likewise, it cannot be said that small necessarily means best. Perhaps the issue is more complex than size – is there something else that contributes to a terminal’s success?
To truly understand this issue, we must look at each element in detail – passenger experience, operational efficiency and commercial effectiveness – to really understand the impact of scale.
On entering or passing through a space, people will automatically access, analyse and react to the environment around them. This reaction will occur both consciously and subconsciously and will usually lead to both psychological and physiological effects.
Mehrabian & Russell (1974) noted, “The three fundamental dimensions that affect human behaviour in an environment are pleasure, arousal and dominance”. Put simply, people feel most comfortable when they are in an environment that they understand, feel safe in and have some control over – one that provides a sense of wellbeing.
But how do people perceive and engage with their environment? Research has shown that perception and engagement will be influenced by the following factors: scale and proportion, enclosure and boundaries, and legibility and navigability.
To create the optimum space, it is important to ensure that each of these factors is considered in partnership.
In summary, the success of a space in terms of passenger experience cannot be judged solely by scale alone. How successfully each of these factors – scale and proportion; enclosure and boundaries; and legibility and navigability – is optimised within a given space, regardless of the size, will determine how positive the resulting passenger experience will be.
Operational efficiency and commercial effectiveness
Within terminal design, we have seen a continued trend towards centralising operational processes into a single ‘central’ facility.
If we look at Heathrow’s terminals for example, security search, immigration, connections and customs are all located in a single centralised facility.
This is not only for space optimisation but it can be argued that control authority stakeholders distinctly favour singular centralised process facilities as this results in efficiencies in resource management.
This trend for singular centralised processes continues when designing the retail offering. If we look again at Heathrow and their established policy for all existing and future terminals, there is a desire to incorporate a single walkthrough World Duty Free store immediately after security search.
The rationale behind this is that 100% of passengers are exposed to the retail offering, which in turn guarantees maximum penetration.
In addition, the current commercial/retail planning policy at Heathrow is to encourage footfall past as much retail frontage as possible on the way to the gates and to minimise the need to duplicate unit types and specific stores.
This is a not a unique proposition, and indeed it is a principle that has been employed in HOK’s proposals for the development of Riyadh’s King Khalid International Airport.
This design principle, of course, is wholly supported by the retail tenants whose commercial performance will be affected by maximising exposure, increasing their efficiency and maximising spend per square foot of retail space.
While this works well for Heathrow’s terminals given their relatively modest scale, there is a point at which centralising facilities becomes problematic.
This occurs for a number of reasons – firstly, the scale of the facility and the management of passenger flows into and out of the facility, in other words managing and balancing demand. Secondly, managing the walking distances to a single facility where the terminal is very large and dispersed, and thirdly, with large commercial facilities, ensuring that the whole of an area is ‘shoppable’ without the need for duplication.
This ‘point’ will vary depending on the configuration of the building but there are a number of examples worldwide such as Beijing’s T3 and Frankfurt’s T1 & T2 where both operational and retail facilities have been split and decentralised due to either scale and or/balancing demand and operational effectiveness.
Whilst it cannot be said that a decentralised design leads to reductions in operational and commercial effectiveness, what can be said is that the size and scale of a building can influence both operational and commercial considerations.
Moreover, it is not just size that influences design but also the specific configuration, arrangement and inherent constraints of a terminal that need to be considered when looking at building successful spaces.
There is a fine balance to be struck between maximising operational efficiency and commercial return without sacrificing a direct, convenient and humane passenger journey.
So does size really matter? In short, yes it does.
Size and scale are crucial factors to consider when looking at terminal design. Get it wrong and your customers could feel overwhelmed, uncomfortable and lost, resulting in poor passenger experiences, reduced operational efficiency and retail offerings falling short of their potential.
However, it is not just about size – these problems are symptomatic of terminals both large and small.
As airport terminals continue to grow ever larger in future, the key will be creating intuitive design that provides both the space but also the comfort and ease that passengers need whilst reconciling the need to maximise non-aeronautical revenue.
The world’s best airports have secured such a title not because of their size, but rather because they hit the sweet spot where the scale, proportion, legibility, navigability and characteristics of the architecture are optimised – and, it is accompanied by high standards of customer service. The challenge for airports of tomorrow is to ensure they do the same.
As we move towards the future, the traditional concepts of ‘optimum’ sized terminals are already starting to shift and we at HOK predict that there will be a maximum ceiling for the size and capacity of the centralised model and a shift towards decentralisation.