Eric Greenwell wrote:

I'm wondering if a transponder-equipped glider would be an aid to search
and rescue people. I've heard that the radar tracks can be obtained from
ATC, but not if S&R people actually do that, and if it can be done in a
timely fashion (less than 24 hours, say).

What are people's experience with this use of transponders for location
of downed aircraft, especially gliders?

Unless the aircraft has gone down in a relatively flat area with good
primary and secondary radar coverage, the final resting place of a missing
aircraft is only marginally easier than guesswork. I have flown SAR
missions for missing aircraft west of Sydney, Australia and in one case
after a week of sorties the search was called off. The aircraft was found
1 month later by bush walkers almost 80nm from the last radar return in
heavily wooded and mountainous terrain. Both pilots survived the impact
but died (probably within 2-3 days after impact) of burns and other
injuries sustained in the accident. The ELT was also destroyed in the
post-impact fire, which obviously wouldn't be likely in a glider.

If their job isn't any harder than it would be searching for an
ELT-equipped glider, people with transponders could be exempted from
also installing an ELT; people with neither might decide the money is
better spent on installing a transponder.

Modern digital ELT's have some major advantages over transponders:
1. they only activate when needed (usually)
2. they have an internal power source
3. they have global coverage (Australia has bugger-all radar coverage)
4. many have built-in GPS to transmit exact location to SAR authorities
5. digital ELT's can also be programmed to transmit registration/owner
details to SAR authorities too.
6. when an ELT/EPIRB transmission is received, it is considered "real" until
*verified* a false +ve. A radar blip that disappears wont initiate an
emergency response until much later (compared to ELT transmission).

In short, if I'm a downed pilot requiring assistance, I'd much rather be
relying on an ELT/EPIRB than some boffin starring at a radar console

Cheers,

James
--
Kerr's Three Rules for a Successful College:
Have plenty of football for the alumni, sex for the students,
and parking for the faculty.