All retractable landing gear systems must have some means of ______ the gear if the primary method fails.

• A. Lowering
• B. Raising
• C. Locking
• D. Stowing

Answer: (A)

Redundancy in gear extension is the key idea. Retractable landing gear must have a backup way to bring the gear down if the primary method (usually hydraulic or electrical) fails, so the aircraft can land safely. This backup mechanism is all about lowering the gear from the up position to the down and locked position, ensuring the wheels are deployed for touchdown. Without a means to lower the gear by another method, a safe landing could be impossible in an electrical or hydraulic failure.

Lowering is the best answer because it describes the action of moving the gear into the down position. The other options describe different actions that don’t fulfill the requirement: raising would move toward up, locking is about securing the gear once it’s in place, and stowing is retraction into the wheel wells.