Originally Posted by
ZOOKER
If the original design with the remote pier structure had been built, I wonder if the present works would be taking place? EGLL has ditched 'cul-de-sacs' in favour of a toast-rack' design at T5, and other airports have done the same. Yet EGCC are happy building more cul-de-sacs.
It really all depends on what the intended use of the airport is, how your site is laid out and a number of other factors. There are plenty of airports that are still building piers, where the use case and land constraints are appropriate. The linear, "Toast-rack" concourse idea came about in the 1970s, primarily for airports where much of your traffic would not interface with the kerb, e.g. connecting traffic. For those airports with lots of kerb interface (O&D) circular and linear terminals were the rage. These fell out of fashion with the rise of security check-points. However, the toast-rack really only makes sense with lots of connecting traffic that doesn't need to flow through the main terminal, plus adequate and appropriate space to build it in. The quintessential toast-rack design is ATL, which now has 6 parallel concourses situated perpendicular to and between the parallel runway complexes; DEN is the same concept but scaled up a lot to take advantage of copious land. LHR is substantially the same runway layout (now) so this can make a lot of sense. Even though ATL stuck with the original concept for over 20 years it was the rise of O&D, especially O&D international traffic plus layout constraints that broke the plan. In 1996 ATL opened a new international concourse (E). However, all arriving passengers had to be rescreened and mixed with connecting passengers. When the Maynard Jackson Terminal and concourse F were build they couldn't keep the toast rack structure, and future expansions to the international terminal are likely to have widely spaced piers.
MAN's runway layout and apron space is completely different from that of ATL, DEN, LHR, etc. As such it isn't nearly as efficient to use the toast-rack configuration. Further, unless they were to complete reconfigure the whole land-side/air-side interface you couldn't efficiently create a terminal layout similar to that use in DTW. As such piers, with blind alleys (they are not true cul-de-sacs as they don't have the bulb at the end) can be the most efficient use of the space. The key is that you don't block the alley with a single aircraft pushing back. This requires more widely spaced alleys and multiple taxi-lanes. A good example of this kind of layout is PHL where the new construction, A-west, and concourse F are spaced far enough apart from A-east and Concourse E respectively to allow for dual taxi-lanes. MAN is somewhere in between a single and duel taxi-lane concept, where there are definitely dual lanes in some alleys for Code C aircraft, but single lanes for Code D+ aircraft. The original satellite pier concept for T2 had a very narrow pier in what is the grass strip. This would not have been wide enough to accommodate the necessary flows of passengers and to widen it would have created effective blind alleys for larger aircraft as the taxi-lanes in certain areas would have been limited to Code C. Of course this could have been solved by greatly expanding the ramp footprint, but the layout would have still be less efficient than widely space piers.