Which type of alterations are considered major according to 14 CFR Part 43, Appendix A?

The determination that only those alterations listed in aircraft specifications issued by the FAA are considered major is rooted in the regulatory framework established by 14 CFR Part 43, Appendix A. This appendix provides a clear definition of what constitutes a major alteration. According to the FAA, a major alteration is one that significantly changes the configuration, structural strength, or operating characteristics of the aircraft as originally designed.

The FAA’s specifications delineate specific alterations that are categorized as major because they have the potential to affect the aircraft's safety or airworthiness. Therefore, alterations must be evaluated based on whether they fit within the scope of those FAA specifications to be classified as major.

In contrast, other options presented do not encompass the comprehensive regulatory definition. For instance, stating that all alterations performed on any aircraft are major ignores the specific criteria set forth. Similarly, referencing alterations found in manufacturers' maintenance manuals or modifications using approved components does not address the regulatory definition that focuses on FAA-issued specifications. These alternatives do not capture the essential specificity required to classify alterations correctly as major under the regulation.