Science: All-Seeing Tower

The New York Port Authority this week dedicated the world’s biggest, most modern airport control tower. The new $1,000,000 structure, rising 150 ft. above New York’s International Airport at Idlewild, on the Atlantic Ocean side of Long Island, is packed with electronic equipment: six radarscopes,’ 13 radio receivers, two transmitters and connections to ten more’ transmitters spotted around the airport. It is also equipped with the newest wrinkle in radar control: the A.S.D.E. (Airport Surface Detection Equipment), which looks not up but down, and displays on its broad scope a living, moving map of every detail on the huge field (4,900 acres).

On A.S.D.E. the runways show up as black bands outlined by radar reflections from the knee-high grass that grows on their margins. Airplanes moving along them are not mere shapeless blobs; they are sharply defined bright bars, and experienced radarmen can even tell one type of plane from another. A car or truck shows up as a smaller rectangle, and a man who steps out of one shows as a bright dot. Any obstacle on a runway, such as a misguided truck or a disabled airplane, is spotted at a glance.

With A.S.D.E., the International tower will be able to follow planes right up to the unloading point, avoid the danger of collision on the ground. The only complaint so far is that the new radar is a little too sharp-sighted. Recently a truck was sent out to investigate what looked like a dangerous obstacle. It proved to be a fringe of grass that had poked up a few inches through a crack in a runway.