STAGE 1: DISTRESS BEACONS
In the event of an emergency, a distress beacon signal is activated either manually or automatically depending on beacon type. There are several beacon variations - a few of the main types are listed below. For GA and gliding, the key beacons are ELTs and PLBs. EPIRBs are associated with marine use. Cospas-Sarsat beacons operate in the 406MHz frequency range, and many include an additional 121.5MHz homer for the last few miles of the rescue.
An EPIRB (Emergency Position-Indicating Radio Beacon) can be installed on a boat, integrated into a life-jacket or used by individual crew or passengers. They can be automatically (using a hydrostatic release mechanism) or manually activated.
By Paul Isaacs