Diligence evidence
Testing the AD status list against the data-room source package
This review tests whether the AD compliance status offered in a seller's data room is actually supported by the files uploaded around it. Working from the AD status list, it traces each applicable directive to accomplishment evidence in the data-room folders, index exports, and Q&A responses, and flags every AD shown closed or not-applicable without the record that proves it. Acquisition and lessor diligence teams run it during the pre-purchase or pre-lease window, while the seller still answers questions. The finding set is an exception list formatted for the diligence exception schedule.
When this review is needed
- The data room has opened and the AD status list is the anchor document for airworthiness position.
- The seller's Q&A answers cite compliance records that the folder structure does not obviously contain.
- The status list shows terminating action on repetitive ADs and the deal price assumes it.
- Diligence must produce its exception schedule before the review window closes.
The problem
An AD status list is a claim, and data rooms are built to make claims look supported. The evidence behind a closed AD may be a work order in another folder, a line in a check package, or nothing at all, and the reviewer only finds out by tracing each directive individually. Sellers rarely misstate deliberately; the list was exported from a system whose backing documents never made it into the upload.
What gets reviewed
- Applicability screening of the status list against the aircraft, engine, and appliance configuration
- Each AD shown complied-with traced to accomplishment evidence in the data room
- Not-applicable dispositions tested against the stated applicability basis
- Repetitive AD intervals and next-due calculations checked against utilization data in the room
- Terminating actions verified to the modification or inspection records that effect them
- Q&A responses reconciled against what the uploaded files actually show
Scope this review
Tell us the asset, the event, and the evidence in scope, and we will outline a focused first engagement.
Send a representative, redacted record set and we will scope the review.
What gets validated
- Every complied-with entry cites a document that exists in the room and describes the required action
- Method of compliance on the evidence matches a means the AD accepts
- Not-applicable calls rest on configuration or serial-number facts the room can demonstrate
- Repetitive AD next-due dates reconcile with the times and cycles the room reports
- Superseded and revised ADs are tracked to the current revision, without orphaned prior actions
Evidence normally required
- The AD status list as offered in the data room
- Data-room access with the folder index or export
- Configuration data: serials, modification status, and installed equipment
- Utilization statements current enough to check repetitive intervals
- The Q&A log to date
Common discrepancies
- Closed ADs whose only support is the status system's own export, circular by construction
- Terminating modifications claimed without the embodiment record in the room
- Not-applicable calls based on configuration assumptions the uploads contradict
- Engine and APU ADs missing entirely because the room was built around airframe records
What is at stake
An AD accepted as closed without evidence becomes the buyer's problem at the next review, when the seller is gone and the accomplishment record may be unrecoverable. If it involves a repetitive inspection wrongly shown terminated, the operational and cost consequences land immediately after delivery.
Move from findings to resolution
Move from findings to a documented resolution path.
How the work runs
Screen applicability
Establish the applicable directive set from configuration, serials, and registry before reading the list.
Trace each disposition
Follow every complied-with, not-applicable, and terminated entry to evidence in the room.
Check the arithmetic
Reconcile repetitive intervals and next-due points against the room's utilization data.
Format for the schedule
Deliver exceptions with search trails and draft Q&A for the transaction lead.
What the buyer receives
- An AD-by-AD exception list ready for the diligence exception schedule
- A source map linking each supported entry to its data-room evidence
- Targeted Q&A questions for the seller on each unsupported disposition
Who uses the output
How the work fits into the transaction or program
AD verification usually runs first among the data-room record checks because its findings move price and condition terms directly. Its output feeds the exception schedule, drives the sharpest Q&A of the diligence window, and sets expectations for how much of the seller's remaining records can be taken at face value.
Jurisdiction-specific considerations
AD obligations arise under 14 CFR Part 39 for FAA-registered aircraft, and EU 1321/2014 requires the continuing-airworthiness records to demonstrate AD status for EASA-managed assets. Where the aircraft will change registry at closing, the incoming authority's directive set applies going forward, so the review notes state-of-design directives that the current status list may lawfully omit but the buyer will inherit.
Regulatory limits
The review reports what the data room does and does not substantiate. It does not determine airworthiness, direct compliance action, or adjudicate whether a given method of compliance was acceptable when performed; those questions belong to the authorities and the parties' technical advisors.
What this review does not cover
- Physical inspection of the aircraft against claimed AD accomplishments
- Compliance planning for ADs found open
- Negotiation of the exception schedule with the seller
Specific to this review
- A status export can never validate itself; the review treats system exports as claims and only counts documents created at the time of accomplishment as evidence.
- Repetitive AD next-due errors are usually utilization-data errors in disguise, so the times and cycles in the room get checked before the intervals do.
- Data rooms indexed by document type hide engine AD evidence inside shop-visit packages, where only a package-level read will find it.
- Sellers answer Q&A fastest when the question cites the exact folder and file already inspected, so each exception records its search trail.
Sources
U.S. Government (eCFR). The legal basis for issuing and enforcing Airworthiness Directives on U.S.-registered products.
U.S. Government (eCFR). Records an owner or operator must keep, including total time in service, current status of life-limited parts, and AD compliance.
European Union / EASA. Continuing airworthiness, maintenance records, CAMO responsibilities, and the airworthiness review process in the EASA system.
Frequently asked questions
The seller's CAMO says all ADs are complied with. Why trace them individually?
Because the deal buys the evidence, and a CAMO statement summarizes a system the buyer cannot see. Individual tracing regularly finds a handful of dispositions the uploaded files cannot support, and those are exactly the items worth raising while the seller is still obliged to answer.
Relevant glossary terms
Related pages
Where this fits
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