Danger: Airplane Crossing
Controlling airplanes on the ground is a thornier problem than controlling them in the air.
- By Michael Milstein
- Air & Space magazine, August 2007
(Page 6 of 6)
Now San Diego has a new tool to keep pilots on track: prototype FAA warning lights that signal pilots to stay off the runway when it’s occupied. Consider it a $6 million stoplight. They’re called runway status lights, and they’re embedded in the pavement at key runway intersections. When airport radar detects an incoming airplane within a mile of the airport or a departing airplane accelerating above 34 mph, the red lights switch on. It’s a clear no-go signal to waiting pilots.
There’s a delicate balance at an airport this busy: It can’t afford lights that slow traffic like an ill-timed stoplight on a busy highway. These lights switch off just before it’s safe to cross, because waiting airplanes will take a few seconds to spool up their engines before they actually begin moving onto the runway. By that time, the runway will be clear.
Similar “stop bars” of red lights built into the intersections at major European airports, such as London’s Heathrow, make incursions a non-issue there, the NTSB says. U.S. Department of Transportation studies of past runway incursions suggest that runway lights would have alerted one or both of the pilots in about 65 percent of cases. The lights, combined with the slow but still helpful AMASS system, would catch about 85 percent of all incursions, the studies found. A similar prototype in Dallas won raves from pilots. A single Dallas runway may handle 450 flights per day, with 500 runway crossings mixed in. More than 90 percent of pilots surveyed said the lights would reduce incursions. The FAA now considers the lights very promising, and will decide later this year whether to expand the program to other airports.
Last March, FAA Administrator Marion Blakey eliminated an FAA requirement that electronic cockpit maps work in the air as well as on the ground. They can now be developed for ground-only use. That will “change how pilots safely navigate runways, the way GPS changed the way we drive our cars,” she said. “I’ll say it plainly: It needs to be in the cockpit. It’s ready, we’re ready, and aviation needs it.”