If the A hydraulic system is lost, how can the landing gear be lowered on the 737?

If the A hydraulic system is lost, how can the landing gear be lowered on the 737?

• A. The landing gear can be lowered by cranking to release the locking mechanism and let it free-fall into the down-and-locked position.
• B. The B system automatically lowers the gear.
• C. Nose wheel steering lowers it.
• D. The Standby system lowers it.

Answer: (A)

When hydraulic power for the landing gear is unavailable, the 737 provides a manual extension path. You use a manual crank to unlock the gear uplocks, allowing the gear to free-fall into the down-and-locked position. This mechanical release and gravity-driven extension is the designed fallback to ensure the gear can deploy even without A-system hydraulic power. The other options don’t provide a reliable, manual extension path: the B system doesn’t automatically lower the gear just because A is lost, nose wheel steering has no role in gear deployment, and the standby system isn’t the intended method for gear extension when A is failed.

When hydraulic power for the landing gear is unavailable, the 737 provides a manual extension path. You use a manual crank to unlock the gear uplocks, allowing the gear to free-fall into the down-and-locked position. This mechanical release and gravity-driven extension is the designed fallback to ensure the gear can deploy even without A-system hydraulic power. The other options don’t provide a reliable, manual extension path: the B system doesn’t automatically lower the gear just because A is lost, nose wheel steering has no role in gear deployment, and the standby system isn’t the intended method for gear extension when A is failed.