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

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

Answer: (D)

Having a means to lower the gear if the primary extension method fails is essential for a safe landing. The gear must move from its retracted position to the down and locked position even when the main hydraulic or electric system isn’t working. Aircraft designs provide an alternate extension method—such as a manual hand crank, an alternate hydraulic/air system, or gravity feed—to ensure the gear can still be deployed. This is why lowering is the correct concept: it describes the action needed to deploy the gear for landing when the primary method is unavailable. Raising the gear wouldn’t allow landing gear to deploy; locking is about securing the gear after deployment, and retarding isn’t relevant to extending the gear.