Volume 8, Number 3     May/June 2000

Mapping Mission Yields Safer Flying

The recent Space Shuttle Endeavour mission (STS-99) is likely to help make flying safer through NASA's Aviation Safety Program (AvSP). AvSP is working with a number of industry teams to create and refine Synthetic Vision, a revolutionary cockpit display system that could give pilots a clear, electronic picture of what is ahead outside their windows, no matter what type of weather or the time of day.

NASA researchers envision a system that would use new and existing technologies to incorporate data into displays in aircraft cockpits. The displays would show terrain, ground obstacles, air traffic, landing and approach patterns, runway surfaces and other relevant data to the flight crew.

The mission of Endeavour was to produce the most accurate and complete topographic map of Earth's surface ever assembled. AvSP, headquartered at NASA's Langley Research Center in Hampton, Virginia, will use this terrain information, which could also be used to help develop Synthetic Vision for pilots and make flying commercial and private aircraft safer.

The Shuttle Radar Topography Mission (SRTM), designed to collect three-dimensional measurements of nearly 80 percent of Earth's land surface with an accuracy of better than 53 feet, is an international project sponsored by the National Imagery and Mapping Agency, NASA, the German Aerospace Center and the Italian Space Agency. Scientists will then use the three-dimensional images to generate computer versions of topographic maps, called digital elevation models, which can be used for a large number of scientific, civilian and military applications.

SRTM builds up Spaceborne Imaging Radar-C (SIR-C) technology that flew twice on Endeavour in 1994. To collect the topographic images, engineers added an almost 200-foot-long mast, additional C-band imaging antennas and improved tracking and navigation devices. The mast, the longest rigid structure ever flown in space, extended sideways from the orbiter's cargo bay. The antennas at the tip allowed the system to acquire stereo-like radar images of Earth's surface through a technique called interferometry.

Limited visibility is the greatest contributing factor to the world's deadliest aviation accidents, according to Michael Lewis, AvSP director. NASA tested a prototype of Synthetic Vision in flights over Asheville, North Carolina, last year. Engineers loaded an experimental terrain database that had been augmented by sophisticated computer-rendering techniques onto a "flying simulator" research aircraft owned by the U.S. Air Force. During tests, pilots assessed how those three-dimensional images of the area compared with what was really outside the window.

It is expected to take about 18 months to process the terrain data from the Shuttle mission. AvSP officials hope a Synthetic Vision system can be available commercially in five years.

NASA's AvSP is a partnership with the Federal Aviation Administration (FAA), the Department of Defense, aircraft manufacturers and airlines. This partnership supports the national goal announced by President Clinton to reduce the fatal aircraft accident rate by 80 percent in 10 years and by 90 percent over two and a half decades.

In addition to Langley, three other NASA field installations are working with the FAA and industry to develop affordable technologies to make flying safer: Ames Research Center at Moffett Field, California; Dryden Flight Research Center in Edwards, California; and Glenn Research Center in Cleveland, Ohio.

Scientists will use these dimensional measurements collected by the Shuttle Radar Topograpy Mission to generate digital elevation models, similar to this one.

For more information, contact Sherry Sullivan at Langley Research Center. 757/864-2556, s.l.sullivan@larc.nasa.gov For more information on NASA's AvSP, check the Internet at http://avsp.larc.nasa.gov For more information on SRTM, visit http://www.jpl.nasa.gov/srtm Please mention you read about it in Innovation.