Which is an appliance major repair?

• A. Replacement of a wing skin panel
• B. Overhaul of a hydraulic pressure pump
• C. Repainting the fuselage
• D. Installation of a new landing gear

Answer: (B)

Focus on what counts as an appliance and what a major repair entails. In aircraft maintenance, an appliance is a non-structural device that performs a function, such as a pump, valve, motor, or generator. A major repair on an appliance means disassembling the unit, inspecting it, replacing worn or defective parts, reassembling to the original specifications, and testing to confirm proper operation.

Overhauling a hydraulic pressure pump fits this definition perfectly. It involves tearing down the pump, checking for wear, replacing seals and worn components, reassembling, and verifying the pump works correctly within the hydraulic system. This is a substantive, regulated repair to a non-structural device that restores it to like-new condition.

In contrast, replacing a wing skin panel addresses airframe structure, which falls under airframe repairs rather than appliance work. Repainting is cosmetic and not a repair to an appliance. Installing a new landing gear changes hardware and potentially certification for a system and structure, but it’s classified as an installation or major modification rather than an appliance repair.