By Daniel Kane, Everette Aviation LLC
Introduction
Two documents show up in nearly every well-run aircraft transaction: a pre-buy inspection report and an appraisal. Because both involve an expert examining the aircraft and both influence whether the deal closes and at what price, buyers frequently treat them as interchangeable — or worse, assume that having one means they don’t need the other. Sellers sometimes make the opposite mistake, pointing to a clean pre-buy as proof of value, or to a favorable appraisal as proof of condition.
They are not the same thing. A pre-buy inspection answers a question about the machine: what is its physical and records condition, and what is wrong with it? An appraisal answers a question about the market: what is this aircraft worth, and to whom, under what definition of value? Each answers its question well and the other’s question poorly. Understanding exactly where each one stops is the difference between a well-protected transaction and an expensive surprise.
What a Pre-Buy Inspection Is
A pre-buy inspection (or pre-purchase evaluation) is a technical examination of the aircraft performed by a mechanic or maintenance facility on the buyer’s behalf, before closing. Its scope is negotiated — anything from a records review and a walk-around to a deep inspection with panels opened, borescopes run, and fluid samples analyzed — but its purpose is constant: identify discrepancies, airworthiness issues, and looming maintenance exposure before the buyer owns them.
A thorough pre-buy typically covers:
- Physical condition — corrosion, structural damage or repairs, leaks, wear, and the general state of the airframe, engine(s), and systems;
- Records review — logbook completeness and continuity, AD compliance, evidence of damage history, major repairs and alterations, and whether the paper matches the aircraft;
- Component and inspection status — where the aircraft sits against its inspection cycle, TBOs, and (on helicopters) life-limited component retirements;
- Functional checks — often including a test or acceptance flight, avionics function, and engine performance trends.
The output is a discrepancy list: what is broken, what is worn, what is out of compliance, and what is coming due. In a well-structured deal, that list drives the negotiation — airworthiness items corrected at the seller’s expense, other findings resolved through price adjustment, or the buyer walking away with facts in hand.
What a Pre-Buy Does Not Tell You
Here is what a clean pre-buy report does not establish:
It does not tell you the aircraft is worth the price. A pre-buy has no market component. The inspecting mechanic is not researching comparable sales, market inventory, days on market, or value trends for the model — and is generally neither trained nor engaged to do so. An aircraft can pass a rigorous pre-buy and still be priced 20% above what the market is actually paying for comparable examples. “It inspected clean” and “it’s a fair price” are unrelated statements.
It does not quantify the value impact of what it finds. The pre-buy can tell you the aircraft had a gear-up landing repaired in 2014; it cannot tell you what that damage history does to resale value against no-damage comparables. It can tell you an engine is 300 hours from TBO; it cannot tell you how the market discounts that position versus a mid-time example. Converting condition findings into dollars is valuation work, not inspection work.
It is a snapshot with a negotiated scope. A pre-buy only examines what its scope includes. A records-only review will not find hidden corrosion; a one-day inspection on a complex aircraft is triage, not certainty. Buyers who economized on pre-buy scope have discovered the difference after closing.
It is not an airworthiness certification. Unless it is combined with an actual annual or required inspection, the pre-buy itself does not sign the aircraft off as airworthy — it informs the buyer’s decision, nothing more.
What an Appraisal Is
An appraisal is an independent, supportable opinion of the aircraft’s value, developed by a qualified appraiser under a recognized standard — for accredited appraisers in the United States, the Uniform Standards of Professional Appraisal Practice (USPAP). A credible appraisal:
- States a defined value — fair market value, orderly liquidation value, insurance replacement value, or another definition suited to the intended use, as of a stated effective date;
- Rests on market evidence — comparable sales, current inventory and asking prices, market trend data, and model-specific supply/demand conditions;
- Adjusts for the specific aircraft — total time, engine and component status relative to the half-life baseline, damage history, configuration and mission equipment, avionics, paint and interior, records quality, and program enrollment;
- Is independent — the appraiser has no stake in whether the transaction closes or at what price, which is precisely why lenders, insurers, courts, and the IRS rely on appraisals rather than on the opinions of parties to the deal.
The output is a documented value conclusion that can withstand scrutiny — from a loan committee, an underwriter, opposing counsel, or a tax authority.
What an Appraisal Does Not Tell You
The limits run just as firmly in the other direction:
It does not verify the aircraft’s mechanical condition. Even an appraisal that includes a physical inspection of the aircraft is not a maintenance inspection. The appraiser observes condition, reviews records, and confirms status — but does not open panels, borescope engines, or run diagnostic checks. A desktop appraisal, performed from records and market data without seeing the aircraft, relies on the accuracy of the information provided and says so explicitly in its assumptions.
It assumes the data it is given. If the logbooks presented are incomplete or the component status summary is wrong, the value conclusion inherits the error. This is exactly the gap a pre-buy exists to close — physically verifying that the aircraft matches its paper.
It does not find what is hidden. Corrosion behind a panel, a cracked component, a fraudulent logbook entry — these are discoveries for an inspection, not a valuation. An appraisal of an aircraft with an undiscovered defect is an accurate appraisal of the aircraft as described; it is the description that was wrong.
It is not a buy/don’t-buy recommendation. The appraisal tells you what the aircraft is worth under a defined premise. Whether that price, that mission fit, and that risk profile make sense for a particular buyer is a decision the appraisal informs but does not make.
Why Serious Transactions Use Both
The two documents are complements, not substitutes, and they work best in sequence and in conversation with each other:
- The pre-buy protects you from the aircraft. It ensures the machine you are buying is the machine described — airworthy, records-complete, and free of undisclosed defects — and it arms you to negotiate the discrepancies it finds.
- The appraisal protects you from the price. It establishes what the aircraft, as it actually is, is worth in the current market — independent of the seller’s ask, the broker’s enthusiasm, or your own eagerness to close.
- Each strengthens the other. Pre-buy findings feed the appraisal: verified component times, confirmed damage history, and discrepancy lists let the appraiser value the aircraft as found rather than as advertised. And the appraisal converts pre-buy findings into negotiating dollars: knowing what the market discount for a given damage history or maintenance position actually is turns a discrepancy list into a defensible price adjustment.
Lenders institutionalize this pairing for a reason: a financed purchase commonly requires both a satisfactory inspection and an independent appraisal supporting the loan-to-value, because either one alone leaves the collateral question half-answered.
There is one more distinction worth naming: who each professional works for. The pre-buy facility works for the buyer. The broker works for their principal. The appraiser — properly engaged — works for no outcome at all. In a transaction where nearly everyone at the table has an economic interest in closing, the appraisal is often the only document in the file whose author is indifferent to whether the deal happens. That independence is not a technicality; it is the product.
Conclusion
A pre-buy inspection tells you what the aircraft is. An appraisal tells you what the aircraft is worth. Neither answers the other’s question, and a transaction protected by only one of them is exposed on exactly the flank that document was never designed to cover. Buy the thorough pre-buy. Commission the independent appraisal. The combined cost is a rounding error against the price of the aircraft — and a smaller rounding error still against the cost of discovering, after closing, what one of them would have told you.
If you are buying, selling, or financing an aircraft and want an independent, USPAP-compliant opinion of what it is actually worth — before the deal closes rather than after — Everette Aviation can help.
Everette Aviation LLC provides certified, USPAP-compliant aircraft and helicopter appraisals nationwide. Daniel Kane is an ASA Accredited Senior Appraiser and FAA-certificated A&P mechanic with Inspection Authorization. Contact us at everetteaviation.com to discuss your appraisal needs.