Emergency Locator Transmitter (ELT)

Personal Locator Beacon (PLB).

Two types of emergency beacon commonly associated with light aircraft and microlight operations are:

• ELT — Emergency Locator Transmitter
• PLB — Personal Locator Beacon

Both are battery-powered emergency radio transmitters designed to assist Search and Rescue (SAR) in locating people or aircraft in distress.

ELT and PLB Frequencies

Approved ELTs and PLBs used for aviation purposes transmit on:

• 406 MHz — used to alert the satellite-based search and rescue system; and
• 121.5 MHz — used primarily as a short-range homing signal to help search aircraft locate the beacon.

406 MHz Signal

The 406 MHz signal transmits a short digital data burst approximately every 50 seconds.

The transmitted information includes:

• a unique beacon identification code; and
• position information, if available from the beacon or associated equipment.

The signal is detected by the COSPAS-SARSAT satellite system and the alert is passed to the appropriate Rescue Coordination Centre.