NASA TECHNOLOGY TO HELP ON-TIME ARRIVALS
Air travelers frustrated with ever-increasing delays at the
nation's airports may soon look forward to a new technology that
could solve a significant part of the problem.
FAA regulations currently require that planes coming in for
landings be at least 4,300 feet apart. When bad weather moves in,
airports with runways spaced more closely together have to delay
flights, which causes headaches for travelers and costs industries
millions of dollars each year.
NASA's Capacity Aviation Systems Program, led by Ames Research
Center, has been seeking a way to solve this problem, and Airborne
Information for Lateral Spacing (AILS) may be the answer.
The AILS technology was developed at Langley Research Center and
implemented as a joint project with Honeywell Technology Center and
Honeywell Airport Systems. A procedures-based concept that uses
existing or near-term flight-deck technology, AILS allows planes to
safely land more closely together than is currently allowed in
By using Automatic Dependent Surveillance-Broadcast (ADS-B) and
signals from a Global Positioning Satellite (GPS), incoming planes
can determine exactly where they are and can communicate that
information with each other. An AILS display in the cockpits shows
each pilot the nearby traffic.
In the rare event that one of the planes strays off course, the
AILS alerting system lets the pilot know. If that path continues
and the straying pilot does not correct his course, a series of
alerts sound in the cockpit of the plane being intruded upon so the
pilot can take appropriate evasive action.
The system was tested on NASA's B-757-200 aircraft using airline
pilots as test subjects. Initial testing of the system took place
in Langley's cockpit motion facility simulator, and then in-flight
tests were conducted during the summer of 1999 at NASA Wallops
The AILS technology was demonstrated for the first time over
active airspace in November 1999 at Minneapolis-St. Paul
AILS has the potential to enable safe and efficient aircraft
landings on closely spaced parallel runways, moving closer to the
goal of increasing on-time landings, no matter what the weather
conditions. Because of the potential to safely increase capacity,
several major airlines are pursuing this capability.
Additional research will be done at Ames Research Center.
For more information, please contact:
NASA Langley Office
Public Affairs at (757) 864-6124
Visit the AILS web site at: