What FAA form is required for major wood repairs?

The FAA Form 337 is specifically designated for reporting major repairs and major alterations to aircraft, including those involving wood components. This form serves as a critical documentation tool to ensure compliance with aviation regulations and safety standards. When a major repair is performed on a wood structure, it is essential to file this form to notify the FAA of the changes made to the aircraft's structure or systems. This helps maintain an accurate record of the aircraft's maintenance history, which is important for safety regulations and future inspections.

The other forms listed have different purposes; for example, FAA Form 405 is used for experimental aircraft approval, Form 8100 pertains to the issuance of type certificates, and Form 100 is not a standard FAA form recognized for reporting repairs or alterations. Therefore, Form 337 is the correct choice for documenting major wood repairs in the aviation sector.