What should be done if a critical defect is discovered during preflight that affects safety?

• A. Do not dispatch; coordinate immediate maintenance, or divert/return as appropriate per SOPs.
• B. Continue mission and plan a check after arrival.
• C. Note the defect and continue if minor.
• D. Request ground transport fix.

Answer: (A)

When a critical safety defect is found during preflight, the aircraft must not be dispatched. The safest and correct action is to halt the mission and arrange immediate maintenance, or divert/return as appropriate per the operator’s standard operating procedures. This keeps the aircraft on the ground until a qualified technician has addressed the defect, or ensures you land safely and handle diversion if you’re already airborne.

This approach is essential because a safety-critical issue cannot be left unfixed while operating the flight. Continuing, planning to check later, or proceeding with a minor-note approach would expose people to unnecessary risk and violate safety and SOP expectations. Even options that suggest fixing after arrival or routing the fix via ground transport don’t directly resolve the safety issue before flight and can lead to unacceptable delays or unaddressed hazards.