Glossary

Emergency Location Transmitter (ELT)

An ELT (emergency location transmitter) is installed by commercial and private aircraft manufacturers during the production phase. They’re used as a locating aid in the event of an emergency landing. However, some ELTs may be installed on an aircraft later on, if deemed necessary.

Emergency location transmitters are an essential component of the international satellite system for search and rescue. Once activated by impact or high gravity forces, they transmit a distress signal. These signals can be detected by non-geostationary satellites then located by GPS or Doppler triangulation.

An ELT and the FAA

According to the Federal Aviation Administration (FAA) Regulations, all U.S. registered aircrafts must have an emergency locator transmitter installed. Throughout the world, similar aviation authorities have also established similar regulations.

There are four main types of acceptable ELTs installed by commercial and private aircraft manufacturers. This includes:

  • Survival ELT – this ELT is removable in case downed aircraft survivors need to move to a safer location.
  • Automatic deployable ELT – this ELT is attached to the aircraft and automatically activated on impact. It also features a manual activation switch.
  • Automatic portable ELT – this attached ELT automatically activates in the event of an emergency, but is removable from the aircraft as well.
  • Automatic Fixed ELT – this permanently attached ELT activates automatically in the event of a crash.