Propeller De-Ice Built-In-Test duration?

• A. 10 seconds
• B. 20 seconds
• C. 30 seconds
• D. 60 seconds

Answer: (B)

The test is designed to verify the propeller de-ice electrical heating system and its control circuitry by running a built-in self-check. It applies power to the heating elements, monitors electrical parameters (like voltage, current, and resistance) and the health of sensors and switches, and then reports whether the system passes or faults. The duration must be long enough for all blades and circuits to be checked and for readings to stabilize, but not so long that it unnecessarily delays flight.

Twenty seconds provides that balance: it gives enough time for the test to complete a thorough verification across all components and still allow a timely indication of readiness. A shorter test could miss a marginal fault, while longer tests would unnecessarily slow the startup and could be sensitive to transient conditions.