In cockpit checks, which indicators must verify functionality in both test positions?

• A. FIRE; 4 bulbs; each annunciator
• B. FUEL; 4 levels; both annunciators
• C. OIL; 2 bulbs; both cockpits
• D. FIRE; 4 bulbs; both cockpits

Answer: (D)

In cockpit checks, ensuring the functionality of indicators in both test positions is critical for operational safety. The correct answer emphasizes the importance of verifying the fire warning system, which includes checking all fire indicator bulbs as part of pre-flight and operational checks.

The fire warning system must demonstrate functionality in both cockpits—this ensures that both pilot and copilot can be alerted to any fire hazard present in the aircraft. Properly functioning fire indicators are vital because they provide an early warning of potential fire emergencies, which is essential for maintaining safety during flight operations. Checking each of the four bulbs ensures that the system overhead is fully operational and can alert the crew as needed.

While other options mention different systems or parameters, they do not highlight the critical nature of the fire indicators and their necessity in both cockpit positions for emergencies. This aligns with standard operating procedures, emphasizing the fire warning system as a priority in cockpit checks to ensure thorough safety measures are in place.