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  • What is ELT or Emergency Locator Transmitter?

Have you ever thought about what happens if an aircraft is lost? And if it has a mishap, how do you go about finding and rescuing it?

Well, don’t worry, because that’s what the ELT or Emergency Locator Transmitter does: a small instrument that is always inside the aircraft. Do you want to know more about it? Keep scrolling then!


What is the ELT in aeroplanes?

The ELT, or Emergency Locator Transmitter, is an essential safety device in aviation. Its main function is to emit a distress signal in the event of a plane crash, which facilitates the location and rescue of the plane’s occupants.

ELTs transmit on the international emergency frequency, which is 121.5 MHz on the VHF band, and 243.0 MHz on the UHF band. The most modern ones also transmit on the 406 MHz frequency.

And because the internal battery is designed to be on the air for more than 48 hours, there is no need to worry about battery life.

And what is it for?

Well, its purpose is already clear, isn’t it? But here’s the definitive fact:

By incorporating an ELT on board an aircraft, the chances of surviving a plane crash increase by more than 50%. That’s a good enough argument, isn’t it?

How does an ELT work?

The ELT is activated when its accelerometers detect a strong impact, typically in excess of 5g, or by manual activation of a switch in the cockpit by the pilot.

Once the ELT is operational, its signals are received by the COSPAS-SAR-SAT satellites, which send the signals to the nearest emergency centres. From there, the teams start coordinating to search for and rescue them.

Is a black box the same as an ELT?

Not at all. They are two very different things.

An ELT transmits data such as the position, registration number or owner of the aircraft, and only in the event of an accident. However, the black box records all the information of the procedures that are taking place in an ongoing flight.

In short, the black box and the ELT are two essential and complementary elements which, in the event of a plane crash, are crucial for its safety.

Are you now convinced of how important an ELT is in an aircraft?

We hope that you have found this topic interesting and, above all, that you have learned how important this small instrument is for flight safety.

And if you want to continue learning interesting things about aviation, aeroplanes and all this wonderful universe, you have to check out our aviation blog.

You can read about how storms are formed and why they are now named as that; learn what chevrons are and why Boeing planes use them; or find out what the Doppler effect is and identify it in your day-to-day life. Are you going to miss it?

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