Emergency locator transmitters

In search and rescue (SAR) operations, battery-powered distress or emergency radio beacons – known as Emergency Locator Transmitters (ELTs) – are vital aids to the detection and location of aircraft in distress.

On activation, the ELT emits automatic distress signals, which are picked up by the Cospas-Sarsat international search and rescue satellite system. The unique digital signal transmitted by the 406MHz ELT enables almost immediate identification of the specific beacon broadcasting the distress signal, and its location using GPS. A search team can then use the ELT distress signal to home in on the exact location of the aircraft in distress.

A demanding battery application

When a distress signal must be sent, an ELT battery needs to deliver instant energy and maintain it for at least 48 hours. This requires batteries that can:

• endure up to 10 years on standby
• resist extreme temperatures
• resist adverse climate conditions such as extreme humidity

• withstand high levels of vibration.

   

Saft lithium batteries minimise passivation

SAR teams rely on the ELT. Failure of the battery to activate the satellite signal is not an option. That’s why many of the world’s leading ELT manufacturers specify Saft primary lithium batteries (LS, LST,LSG, LSH, LO/G, LM/M). Even after prolonged storage, the Saft cell design keeps passivation effects to a minimum. This ensures that the battery will deliver the power pulses the moment they are needed.