Which action directly supports the aircraft to prevent movement during maintenance?

• A. De-energize hydraulics
• B. Follow lockout/tagout procedures
• C. Support aircraft with jacks
• D. Wear PPE

Answer: (C)

During maintenance, immobilizing the aircraft with a solid, mechanical support is essential. Supporting the airframe with jacks provides direct, physical restraint, lifting the weight off the gear and holding the airplane steady so it cannot roll, shift, or settle while work is underway. This is the direct way to prevent movement.

Other safety steps are important for overall safety—de-energizing hydraulics cuts power to systems, lockout/tagout ensures energy isolation, and PPE protects the personnel. None of these alone physically prevents the aircraft from moving, whereas jacks physically support and stabilize the structure. In practice, use proper jack points and secure stands, often with wheel chocks, to maximize immobilization.