After the cutover
AD compliance data reconciliation for airlines after a system cutover
When an airline migrates, digitizes, or re-indexes its technical records, this reconciliation confirms that AD compliance status in the new environment still matches the source evidence. A records specialist compares the post-cutover AD list to the frozen pre-migration position tail by tail, then samples the accomplishment documents now linked to each directive. The work belongs in the weeks after cutover, before the first authority audit or fleet handover leans on the new data. Deliverables include a reconciliation report, a divergence log with root causes, and corrections ready for the records team to apply.
When this review is needed
- A maintenance-information system cutover just completed and AD status arrived by data load rather than re-entry.
- Paper records were scanned in bulk and indexers rebuilt the links between AD lines and their accomplishment documents.
- Two record sets were merged after a fleet transfer or reorganization and the combined AD list has never been verified.
- An authority audit or CAMO review is scheduled and the airline must show its migrated AD data can be trusted.
The problem
Migration projects prove that record counts match; they rarely prove that meanings survived. Legacy status codes get translated to the nearest available value, repetitive-AD forecasting parameters are re-entered with a different time basis, and scanned evidence lands in the archive without a firm link to the directive it supports. Fleet-level totals look right while individual tails drift away from the truth.
What gets reviewed
- Tail-by-tail comparison of the migrated AD status list against the frozen pre-cutover position
- Sampled verification that documents indexed in the new system actually support the AD lines they are attached to
- Forecasting parameters for repetitive ADs checked for time basis, interval, and tolerance fidelity after re-entry
- Applicability and effectivity filters in the new system tested against the legacy population so no directive was dropped
- Status-code translation reviewed wherever the legacy system used values the new one lacks
- Orphaned evidence identified: accomplishment scans that lost their AD linkage during indexing
Scope this review
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What gets validated
- Each directive present before cutover appears after cutover, or its removal traces to a documented applicability decision
- Sampled complied-with lines open to a legible accomplishment record for the correct tail and directive revision
- Next-due values recompute identically in the new system from the same last-done point and utilization basis
- No status value changed across the migration without a change record explaining why
- Attachment links resolve to the intended document rather than to a neighboring scan from the same batch
Evidence normally required
- The pre-migration AD status export, frozen at the cutover data date
- The post-migration AD status list for the same fleet and date
- The document index or scan manifest from the digitization effort
- Migration mapping rules, including status-code and time-basis translations
- Access to the new system or a full evidence extract for sampling
Common discrepancies
- Legacy partial-compliance codes translated to a plain complied-with value, hiding open work on specific tails
- Repetitive ADs whose next-due moved by weeks because the new system rounds utilization differently
- Directives silently excluded because an effectivity filter was configured for the wrong series or line numbers
- Accomplishment scans attached to the wrong AD after batch indexing keyed on document titles alone
What is at stake
Operating on unverified migrated data means the errors surface at the worst moments: a repetitive AD flagged overdue by an auditor, a compliance claim that cannot be evidenced during an inspection follow-up, or a lease return where the lessor's reviewer finds the new system contradicting the old one. Fixing lines under audit pressure costs far more than fixing them during reconciliation.
Move from findings to resolution
Move from findings to a documented resolution path.
How the work runs
Freeze both positions
Fix the pre-cutover export and the post-cutover list to the same data date so every difference found is real.
Compare line by line
Reconcile the two AD populations per tail, flagging additions, omissions, and value changes.
Sample the evidence
Open the documents behind a structured sample of lines to test that indexing linked the right records.
Classify and correct
Assign a root cause to each divergence and hand the records team an actionable correction package.
What the buyer receives
- A tail-by-tail reconciliation report showing where migrated status agrees with, and departs from, the source position
- A divergence log with a classified root cause for each affected line
- A correction package the records team can apply and later evidence to an auditor
- A short written account of the reconciliation method, prepared for audit presentation
Who uses the output
- CAMO and continuing-airworthiness managers who must stand behind the new system's AD data
- Records staff applying corrections and re-linking orphaned evidence
- Quality and compliance teams preparing for the first post-cutover authority audit
How the work fits into the transaction or program
Reconciliation is the closing act of a migration. The data load and indexing effort get records into the new system; this work proves the new system tells the same story the source documents do. Its output feeds the correction backlog and gives the airline a documented basis for trusting AD data at the next audit, lease event, or fleet transaction.
Jurisdiction-specific considerations
Record-keeping duties survive a migration unchanged: 14 CFR 91.417 and the operator's Part-M obligations attach to the content of the records however they are stored. Where a fleet spans FAA and EASA oversight, the reconciliation also confirms that authority-specific AD populations were neither merged nor cross-mapped during the data load.
Regulatory limits
The reconciliation addresses data fidelity between systems and sources, nothing beyond that. No airworthiness determination is made, the new records system is not certified or validated for regulatory purposes, and the operator's own obligation to keep accurate continuing-airworthiness records remains untouched.
What this review does not cover
- Repairing the migration tooling or re-running the data load itself
- Reviewing maintenance-program or reliability data unrelated to AD status
- Serving as the operator's formal system-validation sign-off
Specific to this review
- Count-based migration acceptance can pass while line-level meaning fails; equal record totals say nothing about whether a single status value survived translation.
- Time-basis conversion is the quietest failure mode: a next-due date that shifts by a small margin stays invisible until a directive goes overdue in service.
- Batch scanning produces plausible wrong links, since consecutive documents from one work order look nearly identical to an indexer working under throughput pressure.
- Auditors at the first post-cutover review routinely ask how the operator knows the migrated data is accurate; a documented reconciliation is the answer that closes the question.
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 vendor already validated the migration. Why reconcile again?
Vendor validation usually proves the load completed: record counts, field mappings, and referential integrity. It seldom proves that a legacy status code kept its meaning or that a scanned document landed on the right directive. Those are content questions, and answering them requires reading source evidence against the new data, which is what this reconciliation does.
Do you check every AD line or a sample?
The list-to-list comparison covers every line on every tail because it is mechanical. Evidence verification works from a structured sample weighted toward repetitive directives, translated status codes, and lines the comparison already flagged, since those carry most of the migration risk.
Relevant glossary terms
Related pages
Where this fits
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