Airframe Inspection: Regulations, Records, and Nondestructive Testing
The inspection framework
Know the difference between an annual inspection (due within 12 calendar months and signed off by an A&P holding Inspection Authorization), a 100-hour inspection (required when carrying persons for hire or giving flight instruction for hire, performed by any certificated A&P), a progressive inspection, and special or conditional inspections. A pilot holding a private certificate may perform the preventive maintenance items listed in Part 43 Appendix A on an aircraft the pilot owns and operates, but may not perform an annual. Maintenance entries follow 14 CFR 43.9 and inspection entries follow 43.11; 91.417 defines what records must be kept and for how long.
Documentation traps
Airworthiness Directives are mandatory and apply by aircraft make, model, serial number, and date; service bulletins are not mandatory unless an AD or an approved program makes them so. Major repairs and major alterations require FAA Form 337. Form 8130-3 is an airworthiness approval tag, not an inspection sign-off. Know who returns an aircraft to service: an IA after an annual inspection, an A&P after a 100-hour inspection or other maintenance.
Nondestructive inspection
Match the method to the material: magnetic particle works only on ferrous parts; dye penetrant needs a clean, nonporous surface; eddy current finds surface and near-surface flaws in conductive metals and needs no couplant; ultrasonic needs a couplant and detects internal flaws; radiography reveals internal structure. Tap testing and visual inspection locate composite delamination.
Worked example
An annual inspection is signed off on November 12, 2024. The next one is due by November 30, 2025, because the inspection must be completed within the same calendar month of the following year, not simply 12 months later.