What ground action verifies proper sealing of gear doors after maintenance?

• A. Visual inspection only.
• B. Use a thermal camera to check seals from outside.
• C. Manual cycling of doors through travel to confirm sealing.
• D. Pressurize wheel wells with air to test seals.

Answer: (C)

Testing gear door sealing on the ground is about ensuring the seals actually contact and seat as the door moves through its full range. Manually cycling the doors with the actual actuators recreates the real sealing condition, letting you observe that the gasket meets the door frame in every position, that there’s no binding or misalignment, and that the latch or over-center mechanism maintains the seal when closed. Static checks like a visual inspection or an external thermal check can miss gaps that only appear when the seal is compressed during motion. Pressurizing the wheel wells isn’t the standard way to verify door sealing and may not reveal how the seal behaves through the door’s travel. So, cycling the doors is the most reliable ground verification of proper sealing.