What action is required to manually shut down the APU in case of a fire?

• A. Activate the fire control lever
• B. Pull the T-handle of the APU control switch
• C. Press the emergency stop button
• D. Disconnect the fuel line

Answer: (B)

The appropriate action to manually shut down the Auxiliary Power Unit (APU) in case of a fire is to pull the T-handle of the APU control switch. This action is a critical step in emergency procedures and serves to initiate a rapid shutdown of the APU by cutting off the fuel and combustion air supply, thereby reducing the risk of further fire spread or damage.

The design of the T-handle mechanism allows for a quick and clear action that can be easily identified and performed in an emergency situation. It is especially important in the context of aviation safety, where time is of the essence in mitigating fire hazards.

While other actions mentioned may pertain to fire response or APU operations, they do not specifically address the immediate requirement for shutting down the APU in the event of a fire, which is essential for effective emergency management.