Final answer:
Non-substantial damage according to the NTSB involves minor issues such as small dents, scratches, or cosmetic damage that do not impact an aircraft's structural integrity, performance, or safety.
Step-by-step explanation:
According to the National Transportation Safety Board (NTSB), substantial damage is typically defined as damage that adversely affects the structural strength, performance, or flight characteristics of the aircraft.
As such, not considered to be substantial damage would be any damage that does not have a significant impact on the aircraft's structural integrity or its ability to fly. Examples of non-substantial damage might include small dents or scratches that have no effect on an aircraft's performance or safety, minor cosmetic damage, or any other damage that can be typically classified as wear and tear or easily repaired without requiring major reconstruction or repair.