FAA air traffic control towers

Early in his presidency John F. Kennedy set out to raise the architectural standard of federal buildings, even those the FAA put up at airports. In April 1962 the FAA's Design Advisory Committee picked Pei to work out a prototype control tower; three months later Pei brought in the engineers Severud Associates for the structure. It was one of the first jobs that his new company, I. M. Pei & Associates, carried out on its own, with Pei as partner and James Ingo Freed as designer. The brief called for a tower as modern as could be, to be repeated nationwide as a lasting emblem of air safety.

Until then each tower had been designed case by case, usually alongside the airport itself and by the same team. The FAA wanted to take charge of their design so as to make siting and form consistent, standardise the control room and cut costs. After the prototype, sixteen towers were built, among them those at Chicago O'Hare (the tallest), Sacramento, Houston and Great Falls, Montana. Requirements then changed and the FAA turned to other designs. In 2019 many of the original towers were still working, some had been superseded by taller ones, at least three had been demolished and several had been landmarked by their communities.

Each tower combines three parts. The FAA had already devised a prefabricated control cab, in aluminium and in two sizes, put together on the ground and craned onto the top; its pentagonal plan limits reflections inside and its sloping walls cut glare. Pei adopted this unusual shape and carried it down to the ground: the concrete shaft, cast in place in board formwork, tapers from the top downwards and leaves room only for a lift, a stair and service risers. The third part is a concrete service building at ground level and sometimes below it: sunk below grade, it did not block the view from the tower or from the cockpits of taxiing aircraft.

The model had to suit different traffic levels, terrain and soils: it allowed for five shaft heights and two kinds of foundation, spread footings or piles, a range that reinforced concrete made possible.

Air traffic control towers.