When is the emergency locator transmitter automatically activated?

The emergency locator transmitter (ELT) is designed to automatically activate in specific scenarios that suggest an aircraft may be in distress or has experienced an accident. The correct answer is linked to the activation of the ELT under conditions that indicate significant structural or operational failure.

Excessive longitudinal forces refer to extreme changes in acceleration that might occur during a crash or a severe incident. When such forces are detected, it triggers the ELT system to activate, allowing it to transmit distress signals for search and rescue efforts. This feature helps ensure that rescuers can quickly locate the aircraft in case of an emergency.

The other scenarios presented do not reliably indicate a situation that necessitates the activation of the ELT. For instance, engine failure may not always lead to a crash or emergency, takeoff does not inherently signify distress, and a drop in cabin pressure is a serious issue but does not directly cause the ELT to activate automatically. Thus, the automatic activation of the ELT during excessive longitudinal forces is specifically tailored to enhance safety and improve the chances of survival after an accident.