When may an ELT be tested?

• A. During the first 5 minutes after the hour
• B. During the last 5 minutes after the hour
• C. Any time after engine start
• D. Only during ground maintenance

Answer: (A)

ELT testing is timed to avoid confusion with real distress signals and to minimize interference with search-and-rescue monitoring. The approved window for a test is the first five minutes after the hour, and the test should be brief, typically only a few seconds, following the manufacturer's instructions. Doing it within this early-hour window helps ensure ground and satellite monitoring will recognize it as a test rather than a true emergency. Testing at other times can be mistaken for an actual alert or could interfere with monitoring systems, and testing during engine start or outside the designated window isn’t appropriate.