In an emergency descent, what is the first action the crew should take?

• A. Turn on cabin signs
• B. Initiate emergency descent
• C. Use crew oxygen masks
• D. Disengage autopilot

Answer: (C)

In a rapid depressurization, the immediate priority is to prevent hypoxia for the crew. Donning and breathing from the crew oxygen masks provides instant oxygen, keeping the pilots conscious and able to think clearly while they organize a safe descent. Once oxygen is secured, the crew can proceed with the descent and other required actions. Turning on cabin signs is a cabin-crew task, not the flight crew’s first move. Disengaging autopilot isn’t the initial step because the aircraft can be descended safely with the current flight control setup, and autopilot can be managed as needed after oxygen is established. Prioritizing oxygen ensures the crew can perform the subsequent actions effectively.