# 14 CFR Part 43, Appendix D: What an annual and 100-hour inspection must cover

> Appendix D lists the minimum an annual or 100-hour inspection must cover. The inspector opens and cleans the aircraft, then checks each group, from fuselage, cabin, engine and landing gear to wings, tail, propeller and radios, for the defects the appendix names.

Source: https://www.aerscheduler.com/regulations/43-appendix-d
Official text: https://www.ecfr.gov/current/title-14/part-43/appendix-Appendix%20D%20to%20Part%2043 (eCFR, current as of 2026-10-15; section last amended 2016-12-30)

## In plain English

- Before inspecting, open all necessary inspection plates, access doors, fairings and cowling, and clean the aircraft and engine. [(a)](https://www.aerscheduler.com/regulations/43-appendix-d#a)
- Fuselage and hull: skin and fabric, systems and components. [(b)](https://www.aerscheduler.com/regulations/43-appendix-d#b)
- Cabin and cockpit: loose equipment, seats and belts, windows, instruments, controls, batteries and all systems. [(c)](https://www.aerscheduler.com/regulations/43-appendix-d#c)
- Engine and nacelle: leaks, studs and nuts, compression and metal in screens, mounts, controls, hoses, exhaust, accessories and cowling. [(d)](https://www.aerscheduler.com/regulations/43-appendix-d#d)
- Landing gear: struts, linkages, retraction, hydraulic lines, wiring, wheels, tires, brakes, floats and skis. [(e)](https://www.aerscheduler.com/regulations/43-appendix-d#e)
- Wings, center section and the complete empennage. [(f)](https://www.aerscheduler.com/regulations/43-appendix-d#f)
- Propeller: blades, bolts, anti-ice and controls. [(h)](https://www.aerscheduler.com/regulations/43-appendix-d#h)
- Radios: installation, wiring, bonding and shielding, antennas. Then anything installed that is not listed. [(i)](https://www.aerscheduler.com/regulations/43-appendix-d#i)

## Common questions

**Is the annual more thorough than the 100-hour?**

The scope in Appendix D is the same for both. The difference is who may sign: an annual needs a mechanic with Inspection Authorization, while a 100-hour can be signed by a mechanic with airframe and powerplant ratings.

**Does the manufacturer's checklist replace Appendix D?**

Appendix D is the minimum. Manufacturers' inspection checklists usually go further, and mechanics generally follow the manufacturer's list as long as it covers everything in Appendix D.

## Official text of 14 CFR Part 43, Appendix D

Scope and Detail of Items (as Applicable to the Particular Aircraft) To Be Included in Annual and 100-Hour Inspections.

(a) Each person performing an annual or 100-hour inspection shall, before that inspection, remove or open all necessary inspection plates, access doors, fairing, and cowling. He shall thoroughly clean the aircraft and aircraft engine.

(b) Each person performing an annual or 100-hour inspection shall inspect (where applicable) the following components of the fuselage and hull group:

  (1) Fabric and skin: for deterioration, distortion, other evidence of failure, and defective or insecure attachment of fittings.

  (2) Systems and components: for improper installation, apparent defects, and unsatisfactory operation.

  (3) Envelope, gas bags, ballast tanks, and related parts: for poor condition.

(c) Each person performing an annual or 100-hour inspection shall inspect (where applicable) the following components of the cabin and cockpit group:

  (1) Generally: for uncleanliness and loose equipment that might foul the controls.

  (2) Seats and safety belts: for poor condition and apparent defects.

  (3) Windows and windshields: for deterioration and breakage.

  (4) Instruments: for poor condition, mounting, marking, and (where practicable) improper operation.

  (5) Flight and engine controls: for improper installation and improper operation.

  (6) Batteries: for improper installation and improper charge.

  (7) All systems: for improper installation, poor general condition, apparent and obvious defects, and insecurity of attachment.

(d) Each person performing an annual or 100-hour inspection shall inspect (where applicable) components of the engine and nacelle group as follows:

  (1) Engine section: for visual evidence of excessive oil, fuel, or hydraulic leaks, and sources of such leaks.

  (2) Studs and nuts: for improper torquing and obvious defects.

  (3) Internal engine: for cylinder compression and for metal particles or foreign matter on screens and sump drain plugs. If there is weak cylinder compression, for improper internal condition and improper internal tolerances.

  (4) Engine mount: for cracks, looseness of mounting, and looseness of engine to mount.

  (5) Flexible vibration dampeners: for poor condition and deterioration.

  (6) Engine controls: for defects, improper travel, and improper safetying.

  (7) Lines, hoses, and clamps: for leaks, improper condition and looseness.

  (8) Exhaust stacks: for cracks, defects, and improper attachment.

  (9) Accessories: for apparent defects in security of mounting.

  (10) All systems: for improper installation, poor general condition, defects, and insecure attachment.

  (11) Cowling: for cracks, and defects.

(e) Each person performing an annual or 100-hour inspection shall inspect (where applicable) the following components of the landing gear group:

  (1) All units: for poor condition and insecurity of attachment.

  (2) Shock absorbing devices: for improper oleo fluid level.

  (3) Linkages, trusses, and members: for undue or excessive wear fatigue, and distortion.

  (4) Retracting and locking mechanism: for improper operation.

  (5) Hydraulic lines: for leakage.

  (6) Electrical system: for chafing and improper operation of switches.

  (7) Wheels: for cracks, defects, and condition of bearings.

  (8) Tires: for wear and cuts.

  (9) Brakes: for improper adjustment.

  (10) Floats and skis: for insecure attachment and obvious or apparent defects.

(f) Each person performing an annual or 100-hour inspection shall inspect (where applicable) all components of the wing and center section assembly for poor general condition, fabric or skin deterioration, distortion, evidence of failure, and insecurity of attachment.

(g) Each person performing an annual or 100-hour inspection shall inspect (where applicable) all components and systems that make up the complete empennage assembly for poor general condition, fabric or skin deterioration, distortion, evidence of failure, insecure attachment, improper component installation, and improper component operation.

(h) Each person performing an annual or 100-hour inspection shall inspect (where applicable) the following components of the propeller group:

  (1) Propeller assembly: for cracks, nicks, binds, and oil leakage.

  (2) Bolts: for improper torquing and lack of safetying.

  (3) Anti-icing devices: for improper operations and obvious defects.

  (4) Control mechanisms: for improper operation, insecure mounting, and restricted travel.

(i) Each person performing an annual or 100-hour inspection shall inspect (where applicable) the following components of the radio group:

  (1) Radio and electronic equipment: for improper installation and insecure mounting.

  (2) Wiring and conduits: for improper routing, insecure mounting, and obvious defects.

  (3) Bonding and shielding: for improper installation and poor condition.

  (4) Antenna including trailing antenna: for poor condition, insecure mounting, and improper operation.

(j) Each person performing an annual or 100-hour inspection shall inspect (where applicable) each installed miscellaneous item that is not otherwise covered by this listing for improper installation and improper operation.

## Related

- [14 CFR 91.409: Annual and 100-hour inspections](https://www.aerscheduler.com/regulations/91-409.md)
- [14 CFR 43.11: What an inspection logbook entry must say](https://www.aerscheduler.com/regulations/43-11.md)
- [14 CFR 43.7: Who may approve a return to service](https://www.aerscheduler.com/regulations/43-7.md)

AerScheduler tracks the annual, 100-hour, transponder, pitot-static, ELT and VOR checks by hours and calendar months, and takes an aircraft off the schedule when its annual lapses. [https://www.aerscheduler.com/features/inspections](https://www.aerscheduler.com/features/inspections)

_The plain-English summary is AerScheduler's reading of the rule, not legal advice. The official text above is the eCFR's, published by the Office of the Federal Register; the eCFR is the current text._