The Aircraft Pre-Buy Inspection Checklist
A pre-buy inspection is the buyer's single best insurance against an expensive surprise. It is not the same as an annual inspection: an annual asks "is this aircraft airworthy today?" while a pre-buy asks "as the buyer, what am I actually getting, and what will it cost me?" Use the checklist below to scope the inspection and to understand the squawks that come back.
Before the inspection
- Hire your own mechanic. Use an independent A&P/IA who knows the type — not the seller's shop. Their loyalty should be to you.
- Agree on scope in writing. Decide up front whether it includes a compression test, borescope, oil analysis, and a test flight, and who pays for what.
- Review the logbooks first. Paperwork problems are often bigger than mechanical ones. See how to review aircraft logbooks before buying.
1. Logbooks & paperwork
- Airframe, engine, and propeller logs present and continuous
- Airworthiness Directive (AD) compliance record, including recurring ADs
- FAA Form 337s for any major repairs or alterations
- STCs and field approvals for every modification
- Weight & balance current and matching installed equipment
- Registration, airworthiness certificate, and current annual sign-off
2. Airframe & structure
- Corrosion in the belly, wing spar, control surfaces, and battery box area
- Skin condition, wrinkles, or mismatched rivets that hint at past damage
- Control surface travel, cable tension, and free play
- Windows and windshield crazing; door and latch fit
3. Engine
- Differential compression test on each cylinder
- Borescope of cylinders for valve, wall, and piston condition
- Oil analysis and a look at the oil filter for metal
- Hours since major overhaul (SMOH) versus the manufacturer's TBO
- Engine mounts, baffling, hoses, and exhaust for cracks and leaks
- Evidence of a prop strike and, if so, the required teardown inspection
4. Propeller
- AD and service-bulletin status for the specific prop model
- Nicks, corrosion, and leading-edge condition
- Grease or oil leaks from the hub (constant-speed props)
- Time since propeller overhaul
5. Landing gear
- Tire wear, brake pads, discs, and hydraulic lines
- Strut extension and fluid leaks
- Retraction system operation and rigging (retractable gear)
- Gear-up or hard-landing history in the logs
6. Avionics & electrical
- ADS-B Out installed and compliant for the airspace you'll fly
- Transponder and pitot-static system certifications current
- Radios, navigation, and autopilot function checks
- Database currency and installed-equipment list matches reality
- Battery condition and signs of chafed or corroded wiring
7. Interior, cabin & safety
- Seat rails and seat locks (a known failure point on some models)
- Seat belts, shoulder harnesses, and placards
- Cabin heater and exhaust shroud — cracks here are a carbon-monoxide risk
- Emergency Locator Transmitter (ELT) battery and function
8. The test flight
- Static and full-power engine performance against book numbers
- Oil temperature and pressure, CHT, and EGT in normal ranges
- Autopilot, trim, and avionics under real conditions
- Any unusual vibration, noise, or handling
Deal-breakers vs. negotiables
Get a written squawk list at the end. Some findings are true deal-breakers — hidden corrosion, undisclosed damage, an out-of-limits engine, or missing logbooks. Most others (worn tires, a weak battery, a due transponder cert) are simply bargaining chips: decide who fixes what, or adjust the price. The goal isn't a perfect airplane; it's knowing exactly what you're buying.
Keep the record after you buy
Once the sale closes, the squawk list and every logbook become your aircraft's permanent history — and the foundation for your own next pre-buy when you sell. Digitizing them makes the whole set searchable and easy to share. That's what Aero Logbooks is built for.
Digitize your logbooks with Aero Logbooks →
This checklist is general information, not maintenance or legal advice. A pre-buy inspection must be performed by a certificated mechanic; consult one for your specific aircraft.