Who must give permission prior to disconnecting the GPU?

The correct answer is that the Captain must give permission prior to disconnecting the Ground Power Unit (GPU). This is essential for maintaining safety protocols and ensuring that all operations are coordinated effectively on the ramp.

The Captain has overall authority and responsibility for the aircraft and its operations, including the management of electrical systems and ground services. They ensure that it is safe to disconnect the GPU, which supplies power to the aircraft while it is on the ground. The Captain communicates with the ground crew and the flight crew to confirm that all systems are ready and that there are no ongoing operations that could be disrupted by disconnecting power.

This procedure minimizes the risk of any electrical issues and ensures that the aircraft is ready for its next phase of operation, whether that be further ground preparations or takeoff. Coordination with the Captain helps maintain operational safety and situational awareness on the ramp, reflecting the standard practices within aviation operations.