Larry Dighera wrote:



Right. And the satellites are able to pinpoint the location of the
ELT signal an order of magnitude better than the 121.5 MHz ELTs. But
if there isn't some improvement in the triggering mechanism, I fail to
understand how there might be less false alarms; they will remain at
99% of the total ELT signals reported I would think.

1) more than a few of the false ELT signals are not from ELTS at all,
but from defective consumer electronics. The frequency migration is
meant to mitigate this somewhat.

2) by being registered, the owner of the device can be contacted or
attempted to be contacted, and this is one of the first steps in the
rescue chain. While search teams are still in the call out and
activation stage, if they get ahold of the owner and he says "no, i just
parked the plane in the hangar, I'm fine!" they can instruct the owner
to go disable/reset his ELT and stop the search process then. Even with
equipment being resold and perhaps not re-registered, this will be a
smaller percentage of devices than having 100% unregistered devices on
121.5.

3) by being stronger, the signals are easier to track. Unfortunately, by
being a burst transmitter, normal carrier wave tracking procedures will
be difficult to implement. The new 406 recievers I've seen sell for 20k.

4) by having location encoded with the signal, "search" becomes "get to
the scene". If off airport this may still require air and ground teams.

Dave