How are gear-linked position sensors used to indicate down-and-locked status?

• A. They provide signals to the cockpit indicating gear is down and properly locked via switches or sensors
• B. They measure airspeed
• C. They control flaps
• D. They adjust cabin pressurization

Answer: (A)

Gear position sensors are tied directly to the landing gear mechanism to verify not just that the gear is extended, but that the locking latches have engaged. As the gear moves to the down position, these sensors detect the angle or position of each leg and the status of the locking mechanism, sending signals to the cockpit indicators that confirm “down and locked.” This gives the crew a clear, reliable indication that the gear is safely extended and secured, so the aircraft won’t attempt retraction while it’s not safe. Redundancy is common, with multiple sensors or switches ensuring the status is still shown even if one path fails.

Other functions listed—measuring airspeed, controlling flaps, or adjusting cabin pressurization—are handled by separate systems and do not provide the down-and-locked gear indication, so they don’t rely on these gear-position sensors.