For how long does an ELT operate after being activated?

An Emergency Locator Transmitter (ELT) is designed to transmit distress signals to aid search and rescue operations. When activated, an ELT typically operates for a duration of approximately 48 hours. This allows enough time for rescue teams to locate the source of the emergency signal.

The functionality of the ELT during this critical time period is crucial as it ensures that aircraft in distress can be located quickly, potentially saving lives. The 48-hour operational window is consistent with international standards and recommendations for ELT performance, ensuring that the signal remains active for a period sufficient for search and rescue operations to respond effectively, while not extending unnecessarily, which could lead to confusion with other operations.

The other durations mentioned in the options—24 hours, 72 hours, and 1 week—either understate or overstate the typical operational life of an ELT, which has been established at the 48-hour mark to balance between reliability and effectiveness in rescue scenarios.