What is the function of the Emergency Locator Transmitter (ELT)?

The Emergency Locator Transmitter (ELT) is specifically designed to transmit a distress signal in the event of an aircraft accident or emergency situation. This signal helps search and rescue operations locate the aircraft and assist in the recovery of its occupants. Typically activated automatically during a crash, the ELT broadcasts on specific frequencies to ensure that it can be detected by search and rescue personnel and aircraft, significantly increasing the chances of a swift response.

The other choices, while relevant to aviation, do not pertain to the function of the ELT. Guiding planes during bad weather, monitoring in-flight engine performance, and recording cockpit voice and data are handled by other instruments and systems within the aircraft, but none fulfill the critical role of signaling for help in an emergency situation like the ELT does.