Repair substantiation
Repair and alteration records review for the engine-module records file
A repair approval source review isolates every repair in an engine-module history that lacks the approved data or disposition behind it. It reads the repair map and shop findings against the engine manual limits, identifying which repairs were standard manual work and which required approval that must travel with the part. Engine records leads run it before a records transfer or when closing out a shop-visit review. The file gets back an annotated repair inventory, with each entry graded as manual-based, approval-supported, or unsubstantiated.
When this review is needed
- A transfer counterparty has asked for the substantiation behind specific mapped repairs.
- Shop findings describe repairs the release paperwork never itemized.
- A repaired part arrived at the last build and its approval package did not arrive with it.
- The repair map has been carried across owners without anyone testing what stands beneath it.
The problem
Engine repairs split into two populations with very different evidence needs: work inside the engine manual, which the manual reference itself substantiates, and work beyond it, which needs approved data from a designated engineer, the type-certificate holder, or an authority-approved repair design. Shop paperwork rarely labels which population a repair belongs to, and when repaired parts migrate between engines at builds, the approval package tends to stay behind.
What gets reviewed
- The repair map and shop findings compiled into one inventory of repair events per module
- Each repair classified against engine manual limits as manual-based or approval-required
- Approved data located for every approval-required repair: repair design, designated-engineer package, or type-certificate holder concession
- Repairs on migrated parts traced to the approval packages that should have traveled with them
- Findings-report repairs reconciled against what the release documents and build sheets acknowledge
- Recurring-inspection or reduced-interval consequences of repairs checked into the tracking record
Scope this review
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What gets validated
- Every manual-based repair cites the manual section and revision that authorizes it
- Every approval-required repair has its approved data present or definitively located
- Repairs described in shop findings appear in the formal repair record rather than only in the narrative
- Approval documents match the part serial, dimensions, and condition they claim to cover
- Post-repair obligations, where the approved data imposes them, appear in the tracking statement
Evidence normally required
- The repair map and any predecessor versions carried with the engine
- Shop-visit findings reports and work scopes for documented visits
- Approved-data packages, concessions, and repair-design approvals held in the file
- Module build sheets and installation history for parts that arrived repaired
- The engine manual revision status applicable at each repair date
Common discrepancies
- A findings-report repair absent from the repair map and every release document
- An approval-required repair supported only by the shop's invoice line
- Approved data on file for a different serial of the same part number
- A repair authorized against a manual revision that later revisions tightened, with no re-evaluation recorded
What is at stake
A repair without visible substantiation invites the reviewer to assume the worse category, work beyond limits done without approval, and one such assumption can spread doubt across every repair the same shop touched. Cures are slow: the approval holder may charge for re-issuance, the shop may have closed, and a repair that cannot be substantiated at all becomes a part-replacement conversation at the owner's cost.
How the work runs
Build the inventory
Merge the repair map, findings reports, and release records into one per-module repair listing.
Classify each repair
Sort entries against the applicable manual revision into manual-based and approval-required work.
Locate the substantiation
Match approval-required entries to their data packages and mark what is absent or mismatched.
Grade and plan recovery
Deliver the graded inventory and the recovery plan aimed at the holders who can still supply data.
What the buyer receives
- An annotated repair inventory grading every entry: manual-based, approval-supported, or unsubstantiated
- A substantiation-recovery plan naming the approval holder or shop for each open entry
- A reconciliation memo aligning the repair map, findings reports, and release documents
Who uses the output
- Engine records leads answering counterparty questions on specific repairs
- Technical reviewers on the receiving side deciding which repairs to challenge
- Shop-visit managers closing the documentation loop while the shop still answers
How the work fits into the transaction or program
Repair substantiation closes the loop the other engine-module checks open: findings reports surface repairs, release documents acknowledge them, and this review asks what authorizes them. Its inventory joins the AD evidence map and LLP verdicts inside the engine trace support file, and its recovery plan usually shares addressees with theirs.
Start with a single asset
Confirm release certificates and component traceability are complete.
Jurisdiction-specific considerations
Under 14 CFR 43, maintenance including repair must be performed using data acceptable or approved as the work requires, with 91.417 preserving the record of it. EASA reaches repairs through repair-design approval under the design rules and continuing-airworthiness records under Regulation 1321/2014. An engine repaired under one regime and reviewed under the other needs each repair judged under the regime that governed its release.
Regulatory limits
The review classifies and locates evidence. It does not approve repairs, does not generate substantiating data, and does not decide whether a part with an unsubstantiated repair may remain in service; that determination stays with certificating personnel and the approval holders.
What this review does not cover
- Engineering evaluation or re-approval of any repair scheme
- Physical examination of repaired hardware
- Commercial negotiation with shops or approval holders over re-issuance
Specific to this review
- The manual-limits boundary decides everything about evidence: the same blend, a few thousandths deeper, moves a repair from a manual citation to an approval package that must exist and travel.
- Findings reports are where undocumented repairs surface, because shops narrate what they saw and did more candidly there than any release form requires.
- Approval packages are serial-specific far more often than teams assume; data approved for one disk does not substantiate its part-number twin.
- Repaired parts migrating at builds are the classic substantiation orphan: the part moves on a release certificate while the approval data stays filed under the previous engine.
- Manual revisions can tighten limits retroactively in effect, since a reviewer reading today's manual will question yesterday's repair unless the applicable revision is preserved in the record.
Sources
U.S. Government (eCFR). Maintenance recordkeeping content and approval-for-return-to-service requirements, including 43.9, 43.11, and Appendix B.
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
Most of these repairs were done years ago by shops we no longer use. Is recovery realistic?
Frequently, yes, because approval holders and shops archive repair-design data longer than they archive correspondence, and a precise request naming part serial, date, and work order gets answered where a vague one dies. The review's value is turning each open entry into exactly that precise request while the transfer clock still has slack.
Relevant glossary terms
Related pages
Where this fits
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