Describe a system on your current aircraft.

• A. Pneumatically actuated landing gear with manual valves
• B. Electronically activated hydraulically actuated landing gear
• C. Electrically driven gear with mechanical latching
• D. Mechanically actuated gear using gravity drop

Answer: (B)

Actuation systems for landing gear are designed to move heavy gear reliably and predictably, so hydraulics are often used for the actual motion because they can deliver high force in a compact package with smooth, controllable movement and built-in redundancy. In modern aircraft, electrical signals from the cockpit or flight controls trigger valves and pumps that drive hydraulic actuators to extend or retract the gear. This setup—electrical control of hydraulic actuation—provides precise commanded movement, fast and safe operation, and multiple fail-safes, which is why it best matches typical aircraft practice.

The other concepts fall short for large airplanes: pure pneumatic systems with manual valves don’t offer the same force or control; an all-electric gear with mechanical latching implies powering the gear directly with electric motors, which is less common for heavy aircraft due to power demands and reliability concerns; and gravity-drop mechanisms rely on gravity alone, which is impractical and unsafe across different attitudes and speeds.