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Form 337s and Aircraft Damage History: Reading the FAA File Before You Buy
RECORDS & DAMAGE There is no Carfax for airplanes. But between Form 337s, NTSB records, and the FAA file, the story is usually there — if you know where damage hides and how it is worded.
Every buyer asks the same question: has this airplane ever been damaged? No single database answers it. What exists instead is a paper trail spread across the FAA aircraft records file, the NTSB accident database, and the maintenance logbooks — and the skill is knowing how each one talks about damage, because none of them uses the word casually.
What a Form 337 actually is
FAA Form 337, “Major Repair and Alteration,” is filed whenever a major repair or major alteration is performed on a U.S.-registered aircraft — work significant enough that it might appreciably affect weight, balance, structural strength, performance, or flight characteristics. One copy goes to the FAA and becomes part of the aircraft’s permanent records file. That permanence is what makes 337s valuable to a buyer: owners change, logbooks go missing, but the 337s filed in Oklahoma City stay.
Reading 337s for damage signals
A 337 is not a confession of damage — plenty document happy things like avionics upgrades, STC modifications, or a new interior. The damage signals are in the repair descriptions: work on wing spars, ribs, and skins; firewall or fuselage structure repairs; landing gear and gearbox work clustered around a single date; propeller strikes paired with an engine teardown; and phrases like “repaired in accordance with” a manufacturer’s structural repair manual. A cluster of structural 337s dated within weeks of each other usually marks an event, even when no document uses the word “accident.”
Where else damage history hides
Cross-checking matters because each source catches what the others miss. The NTSB accident database records investigated accidents and incidents — but plenty of hangar rash, gear-ups, and off-field landings were never NTSB events. The maintenance logbooks hold the day-to-day story — but logbooks travel with the aircraft and can be lost, edited, or “lost.” The FAA file is the backstop: 337s, registration history that hints at salvage buyers or rebuilders in the chain, and airworthiness records. When the logbooks say nothing but the file shows a wing-spar 337, that gap is itself the finding.
What the records cannot tell you
Honesty requires saying it: repairs done without paperwork leave no 337. Records analysis tells you what was documented; a thorough pre-buy inspection by a mechanic who knows the type tells you what the airframe itself says. The two together — records due diligence plus physical inspection — are how careful buyers actually close. Skipping either one is betting the purchase price on the seller’s memory.
Where PlaneLists fits: our $249 Title, Airworthiness & Damage Report catalogs every Form 337 in the FAA file, flags damage evidence, cross-checks the NTSB database, and scores the whole record with a VANT™ 300–850 trust rating — every finding cited to the exact page. Start free with an AD exposure check or an Aircraft 360 profile.
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This article is general information about FAA records, not legal advice and not an airworthiness determination. Pair records review with a qualified pre-buy inspection.