How do you perform a Propeller De-Ice test prior to flight in icing conditions?

• A. On the ground during icing checks, select ON for at least a minute and check for CAS messages
• B. In flight at 2000 RPM with De-Ice ON
• C. On the ground with the switch OFF for 5 seconds
• D. Only after takeoff

Answer: (A)

The test is done to confirm the propeller de-ice system will work when you need it, before you enter icing conditions. Powering the system on while the aircraft is on the ground gives the components time to energize and indicates that the circuit and indicators are functioning properly.

To perform it, switch the propeller de-ice on and leave it energized for at least a minute while on the ground. During this time, monitor the cockpit CAS (the alerting/ annunciation system) for any messages. You should not see fault messages or warnings; the absence of such CAS messages means the de-ice system is operating as expected and ready for flight. If a fault message appears, follow the manufacturer’s procedure before flight.

This approach is preferred because testing in flight or with the switch off wouldn’t verify proper electrical heating and annunciation, and performing the test only after takeoff would expose you to icing conditions without confirming the system is ready.