Cars are equipped with Global Positioning System devices to point out exactly where drivers are when they lose direction, so why isn’t it possible to use GPS to pinpoint the exact position of planes when disaster strikes?
Search and rescue teams took more than 30 hours to find out the wreckage of the Air France plane that went down in the Atlantic Monday. The GPS system on board the aircraft came of no help to those engaged in rescue operations.
Even though details about the fate of Flight 447 remain unsure, in certain air mishaps, this all-important time could spell the difference between life and death for any survivors.
Aviation expert with Eurocontrol, an European organization concerned with a navigation safety, Michel Roelandt, stated that some planes are equipped with GPS systems, but basically these are “dumb” units - like those which are fitted in cars - that receive information on position from satellites but do not send back any data.
So although a flight crew is aware of its precise position above an ocean, the information does not automatically get sent to air traffic control. Someone in the cockpit relays that information through satellite communication when the plane has gone beyond radar range.
Industry experts believe that satellite technology that permits continuous monitoring of the precise position of an aircraft is available, and though plans are underway for its introduction, the cost may be discouraging to some airlines.
Roelandt said, “Airlines often have a contract with a private operator to provide their satellite communications. Some companies pay for it, some have free contracts.”
Most of the GPS satellites in space that keep track of where a commercial aircraft is at any given moment are owned by the United States. Provided an aircraft is within range of between two to three satellites deployed in space, it makes use of them to triangulate its location and transmit the information to the closest ground station through a transponder, according to Bill Waldock, professor of safety science, Embry Riddle University, based in Prescott, Florida.
It is possible too, though not likely, that the position of an aircraft in trouble could be precisely determined with the help of military defense satellites, experts mentioned.
Some American military satellites use heat-sensitive cameras that can scour the skies for missiles and could likely detect an aircraft if it weren’t blurred by clouds, stated John Pike, director with GlobalSecurity.org, a public policy organization that has a Web site for providing news on the defense industry and weapons systems.
Roelandt emphasized the concept of GPS tracking has not been included in any safety review inside the aviation industry. The consensus, in general, has been there is available a trained flight crew that always possesses the ability to be in touch with some person on the ground if an emergency arises.
In the Air France Flight 447 case, it seems there was no time for the crew to get an emergency message relayed.
Just before the plane went down, a four minute exchange of messages to maintain and computers of Air France was initiated by its automatic system, which indicated that “several pieces of aircraft equipment were at fault or had broken down,” according to Pierre-Henri Gourgeon, Air France CEO, on Monday.
