A pre-purchase inspection is only as good as its scope—and the people interpreting the findings.

Yellowstone begins the pre-purchase evaluation with the aircraft’s records, known model concerns and the proposed terms of purchase. Our maintenance team identifies conditions that need substantiation and areas that warrant closer examination, then develops targeted work with the selected facility. This gives the buyer an inspection directed at the aircraft’s particular uncertainties and the evidence needed to decide whether to accept it.

A standard inspection package can provide a useful starting point, but its coverage must be considered against the model, serial number, history and intended operation. A capable facility can perform every requested task correctly while leaving an important question unanswered. Buyer protection depends on the relationship between the scope, the evidence produced and the terms under which the buyer may act on it.

Connect the scope to the agreement

A pre-purchase inspection, or pre-purchase evaluation, is a technical assessment for a prospective buyer before acceptance and closing. It has no single, universally prescribed regulatory scope. The aircraft’s history, maintenance data, authorized access and purchase agreement shape the examination. Its purpose extends beyond establishing whether the aircraft can legally fly on that day to understanding condition, conformity, records, maintenance position, reliability and compliance with the negotiated delivery standard.

The NBAA Aircraft Transactions Guide connects the agreement and evaluation within a multidisciplinary transaction. The EBAA Sales and Acquisition Guide likewise recommends defining the inspection process in the agreement with qualified technical oversight. Access, testing, scope expansion, cost allocation and acceptance deadlines should be addressed while the intended diligence can still shape the terms. Aviation counsel drafts and interprets the agreement; the technical team supplies the aircraft knowledge and inspection strategy needed to inform that work.

Examine the aircraft before commissioning deeper work

Yellowstone brings its own maintenance expertise into the acquisition early. Our team examines available records, operating history, configuration, recurring discrepancies and upcoming requirements, with attention to concerns associated with the model and its installed systems. When access and transaction terms permit, the team also examines the aircraft directly before the deeper inspection. Accessible condition, visible areas and cabin and system functionality can help determine whether to proceed and where specialist investigation is justified.

Records provide direction for that examination. Airframe, engine, auxiliary-power-unit and component status must be considered alongside life-limited parts, serialized-component traceability, airworthiness-directive and service-bulletin status, inspection signoffs and task cards. Damage, structural repairs, engineering approvals, modifications and recurring defects may identify areas requiring closer review. Program enrollment, account status, transfer requirements and missing substantiation can also change the buyer’s exposure. The objective is to use the documentary history to test representations and concentrate physical work where uncertainty matters.

The resulting scope may call for deeper access, functional checks, engine or auxiliary-power-unit evaluation, nondestructive testing, structural examination, leak investigation or avionics verification at a qualified maintenance, repair and overhaul facility. Preliminary examination by Yellowstone informs those tasks; it does not replace specialized maintenance work. Properly authorized maintenance professionals retain responsibility for airworthiness determinations and any required release to service. Yellowstone directs the buyer’s diligence and interprets its implications for the acquisition.

Match the facility to the evidence

Model knowledge should influence both the scope and the facility selected to perform it. Duncan Aviation explains that it uses make-and-model-specific evaluation guides informed by common findings and heavy-maintenance experience. Aircraft age, utilization, geography, prior corrosion or damage, modifications and recent inspections may justify different tasks even within the same model. The facility needs the relevant personnel, tooling, specialist access, capacity and ability to document the work clearly.

An OEM facility may offer valuable engineering access, fleet knowledge and parts support; an independent MRO may have particular expertise in a legacy model, modification or inspection. The choice should follow the work required and the need for independent technical judgment. As findings emerge, the scope may need additional access, testing, manufacturer input or specialist review. Authority for those changes, their cost and any effect on the schedule should already be established, while substantiated recent maintenance may help avoid unnecessary duplication.

Establish what each finding means

Yellowstone evaluates material findings against the relevant maintenance manual, inspection criteria, operating limitations and manufacturer guidance, then compares the evidence with the negotiated delivery standard. Descriptions such as normal wear, cosmetic deterioration or customary practice require that same examination. We use photographs, measurements, test results and supporting records where appropriate to substantiate the technical position. The buyer and counsel can then assess the finding on an identified requirement and documented condition, which provides a firmer basis for negotiating its treatment.

That analysis should explain whether continued operation requires corrective action, further inspection or another restriction, what work would resolve the issue and what exposure would remain afterward. A technically serviceable item may still create reliability, downtime, supportability or resale concerns for a buyer. A system that operates during a demonstration may have a recurring history that warrants investigation, while records sufficient for one purpose may leave questions for an intended registration or program transfer. Airworthiness and contractual acceptance therefore require separate consideration by the professionals responsible for each.

Allocate repair costs from the facts and terms

The purchase agreement governs how inspection expenses, findings and corrective work are allocated. Industry custom may inform negotiations, but saying that a seller does not normally pay for a particular item does not resolve whether the condition exceeds a maintenance limit or conflicts with the agreed delivery standard. A technical requirement establishes what must be addressed; it does not, by itself, determine which party owes the cost. Counsel applies the agreement to the substantiated facts while the representative develops the commercial position.

Duncan Aviation’s guidance on component discrepancies similarly considers the agreement, regulatory guidance and manufacturer guidance in determining discrepancies and responsibility. Depending on the terms and circumstances, a resolution may involve seller-funded work, a price adjustment, a holdback, acceptance of an understood condition or termination. Yellowstone uses governing maintenance data and the delivery standard to support the buyer’s position, including when an item initially assigned to the buyer merits a different allocation. The recommendation should account for the adequacy of the remedy and any remaining downtime or future obligation.

Consider upcoming maintenance as part of diligence

When scheduled maintenance is approaching, Yellowstone examines whether the event’s access and tasks can serve part of the buyer’s diligence. We compare the planned work with the technical questions still to be answered and identify any additional evaluation needed. Where the scope and transaction terms align, we may recommend combining the event with agreed buyer-directed tasks to obtain relevant condition evidence and avoid duplicating access or disassembly. The recommendation depends on the actual coverage; scheduled maintenance does not by itself complete the acquisition evaluation.

The parties need to agree which maintenance tasks will occur, what additional evaluation is required and who pays for each. They must also define how discoveries will be handled, the condition required at delivery and the effect of expanded work on acceptance and closing. The buyer’s technical team should identify any areas the event will leave unexamined. This approach is useful only when the access, evidence and contractual rights support the intended diligence, with no assumption that combining work guarantees a better result.

Conclude with a recommendation

At the end of the evaluation, Yellowstone explains which findings are material, whether proposed repairs resolve them and what exposure would remain after closing. We connect those conclusions to value, reliability, downtime and the intended operation, then recommend what to repair, negotiate, monitor or accept. We also reassess whether the aircraft remains a sound purchase. This gives the buyer a decision grounded in the completed technical work, with the remaining obligations and uncertainties made explicit.

The maintenance facility, technical team, aviation counsel, insurer, lender and escrow provider each contribute within their roles. Our operator-led aircraft acquisition representation connects those inputs through closing and delivery. The technical recommendation should show how the examination answered the questions identified before induction, what changed during the work and why the evidence supports the proposed decision.