Be aware that the information about ELTs contained within the AAIB report linked above is now out of date.
The Cospas-Sarsat satellite system no longer listens on 121.5/243MHz. Unless a beacon transmitting on these frequencies is heard by a ground or air station, no one knows it has been activated. Only 406MHz is now monitored by the Cospas-Sarsat system.
The report is also slightly misleading in that its wording tends to imply that 406MHz beaons do not provide a 121.5MHz homing signal for radio direction finding equipment, when in fact most 406MHz devices retain a 121.5 signal for this very purpose.
Last edited by SyllogismCheck; 28th January 2010 at 22:38.
Reason: typos.