CFM56 repairs & alterations
CFM56 engine repair approval data records review
This review confirms that every repair and alteration recorded on a CFM56 engine rests on approved data and closes with a valid return-to-service entry. It is run by or for a lessor, airline, or asset manager evaluating or transferring a specific engine serial number. It checks damage reports, repair dispositions, the approved-data basis behind each repair, and the sign-offs that returned the parts to service. You receive a repair map indexed to its approval basis, an exception list for unsupported repairs, and a closure plan for the engine under review.
When this review is needed
- An engine has accumulated repairs across several shop visits and the approved-data basis was never consolidated.
- A buyer requires each recorded repair matched to its data source before pricing the engine.
- A shop applied a repair scheme and the paperwork does not state which approved data authorized it.
- An alteration is claimed on the engine but its return-to-service entry cannot be located.
The problem
A CFM56 collects repairs from many shops over its life, and each one is only defensible if it names the approved data that authorized it and closes with a proper return-to-service entry. A repair disposition that cites no data source, or an alteration whose sign-off is missing, sits quietly in the file until a buyer or auditor asks for the basis and finds it was never recorded.
What gets reviewed
- Each recorded repair matched to the approved data that authorized it
- Damage reports and dispositions checked against the repair applied
- Return-to-service entries confirmed for every repair and alteration
- Alterations reconciled to their approval basis and effect on configuration
- Repairs applied under a shop scheme traced to the acceptable data source
- Repeat repairs on one part followed across the shop-visit history
Scope this review
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What gets validated
- Every recorded repair cites approved or acceptable data appropriate to the part
- The disposition on file matches the damage report and the repair actually applied
- Each repair and alteration closes with a return-to-service entry
- An alteration that changes configuration is reflected in the engine's configuration records
- A repair scheme applied by a shop names the data that authorized it
Evidence normally required
- The repair and alteration records for the engine serial number
- Damage reports and repair dispositions from each shop visit
- Approved-data references or repair schemes cited for the work
- Return-to-service entries for the repaired and altered parts
- Configuration records affected by any alteration
Common discrepancies
- A repair disposition that names no approved-data source
- An alteration recorded with no return-to-service entry behind it
- A shop repair scheme applied without stating the data that authorized it
- A repeat repair on one part that exceeds what the cited data allows
What is at stake
A repair without a traceable approved-data basis can force removal, re-inspection, or re-substantiation before the engine transfers, and that work is far more expensive than confirming the basis up front. An alteration with no return-to-service entry leaves the configuration in question and can stall acceptance until the sign-off is reconstructed.
Move from findings to resolution
Move from findings to a documented resolution path.
How the work runs
Map the repairs
List every recorded repair and alteration on the engine across its shop-visit history.
Trace the basis
Match each repair to the approved or acceptable data cited as its authorization.
Confirm the close
Verify a return-to-service entry exists for each repair and alteration.
List the exceptions
Flag repairs with no traceable basis or missing sign-off and set the substantiation needed.
What the buyer receives
- A repair map indexing each repair to its approval basis
- An exception list for repairs and alterations without traceable data
- A closure plan naming the substantiation needed for each open item
Who uses the output
- Engineering deciding how to treat a repair with no traceable basis
- Asset managers pricing the engine against repairs the records actually support
- Records teams assembling the repair substantiation a buyer will require
How the work fits into the transaction or program
The repair review runs before a sale or a register change so unsupported repairs are found while the shops that performed them can still supply the data. Its exception list feeds the substantiation work that has to clear before the engine transfers.
Aircraft-specific considerations
CFM56 parts are repaired repeatedly across a long life and a large installed base, so one component can carry a stack of dispositions from different shops, each under its own data source. The review is scoped to the specific serial number's repair history, since a repair scheme acceptable on one build may exceed the limits for the part as it stands today.
Jurisdiction-specific considerations
Approved data acceptable to the FAA is not automatically acceptable to EASA, so an engine crossing registers has its repairs checked against the basis the receiving authority recognizes, and the review flags any repair that would need re-substantiation.
Regulatory limits
The review confirms that recorded repairs cite a traceable data basis and close with a return-to-service entry. It does not approve a repair, develop repair data, or determine that a part or the engine is airworthy.
What this review does not cover
- Developing or approving new repair or alteration data
- Re-performing or re-inspecting any repair
- Any airworthiness determination on the engine or its parts
Specific to this review
- A repair is only as defensible as the data it names, so a disposition that cites no source is treated as unsupported until the basis is recovered.
- Repeat repairs on one CFM56 part can exceed what the original data allowed, which the review catches by following the part across shop visits rather than reading one disposition.
- The return-to-service entry, not the repair sheet, is what proves the alteration closed, and it is the record most often missing on older builds.
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
What happens to a repair with no approved data on file?
It is carried as an exception until the shop's data source is recovered or an acceptable basis is identified. Left unresolved, the repair can force removal or re-substantiation at the next transfer, so it is flagged while the shop can still supply the record.
Relevant glossary terms
Related pages
Where this fits
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