Which of the following is an example of a major repair?

• A. Splicing of skin sheets
• B. The splicing of skin sheets
• C. Replacing fabric on fabric-covered parts
• D. Replacement of engine mounts obtained from manufacturer

Answer: (B)

In aviation maintenance, a major repair is one that, if done improperly, could appreciably affect structural strength, flight characteristics, or overall airworthiness. The splicing of skin sheets fits this category because the aircraft’s skin is part of the primary load path for the airframe. When skin is damaged, simply patching it isn’t enough—you must recreate the original structural continuity. A splice requires careful workmanship, proper overlapping, fastener patterns, thickness, and often additional inspection or nondestructive testing to ensure the skin will carry loads as intended. That kind of repair directly concerns the airframe’s strength and aerodynamic properties, so it’s classified as major.

Replacing fabric on fabric-covered parts, by contrast, is typically considered a covering repair rather than a structural repair; it affects the surface and appearance more than the load-bearing structure. Replacement of engine mounts is a structural repair as well, since mounts support the engine and transmit its loads to the airframe, but the example that most clearly demonstrates a major repair in relation to the airframe’s skin is the splicing of skin sheets.