How do you notify the pilot of an APU fire?

The proper method to notify the pilot of an Auxiliary Power Unit (APU) fire is through performing the correct hand signal. This is essential because, in situations where there is an emergency, clear and immediate communication is crucial. Hand signals can be seen from a distance and do not rely on electronic communication equipment, which could be compromised in a fire scenario.

Additionally, hand signals are standardized within naval operations, ensuring that they are understood universally by ground crew and pilots alike. This method mitigates the risk of miscommunication that can occur with verbal messages over radio or direct calls, especially in a noisy or chaotic environment. Using a loudspeaker may not be practical in certain conditions, and sending a radio message could cause delays when time is critical.