Collisions with other aircraft are just a fraction of glider-related fatalities. FAA records show that since 1964, 311 people died in 2,085 glider crashes in the U.S. and elsewhere – the vast majority attributed to pilot error or equipment failure.
But FAA’s stated goal is to “achieve the lowest possible accident rate and constantly improve safety,” and requiring transponders in gliders is the easiest problem to fix.
“Most aircraft have transponders,” Chris Dancy, executive director of the Aircraft Owners and Pilots Association, told The Examiner.
In fact, federal homeland security regulations require all aircraft within a 30-mile radius of the nation’s 30 most congested airports carry transponders that can be immediately identifiable to air traffic controllers within Air Defense Identification Zones established after 9/11.
However, in places with smaller airports and less air traffic where transponders aren’t required, gliders – or sailplanes – coexist with general aviation, Dancy says, both relying on visual flight rules (VFR) to stay out of each other’s way.
But as the large number of close calls and collisions show, visual flight rules alone are not enough. German sailplane manufacturer DG Flugzeubgau says on its webpage that transponders provide a “measure of extra flight safety,” and that their universal use on gliders would almost completely eliminate potential collisions with other aircraft, including commercial jets.
Since 1998, the New Mexico-based Soaring Society of America (SSA) has been encouraging its 12,000 members to use transponders in high-traffic areas.
“There’s a large volume of airspace that has extremely low traffic. We encourage voluntary use in high-traffic areas, but you don’t need a red light or a traffic cop at every intersection,” SSA director Cindy Brickner told The Examiner.
Since no transponders manufactured in the U.S. come with a power source, the cost and difficulty of installing one in a non-motorized glider can be considerable.
In 2003, the club petitioned FAA to would allow glider pilots who did have transponders to turn them off when they were out of controlled airspace – about 40 nautical miles from the airport.
Pilots complained they drained the batteries and became inoperable at landing, when they were needed most. It was almost impossible, they said, to carry enough battery power to keep a transponder on in remote areas where few other aircraft venture. But federal regulations require that transponders operate continuously during flight, and the request was denied.
The cost of installing a transponder in a glider can also run into the thousands of dollars, and some compactly built sailplanes have no place to mount them. Portable collision avoidance systems are a cheaper alternative, but since they don’t alert other aircraft to the glider’s presence, they are not enough. — Barbara Hollingsworth
