CFM56 modification status
CFM56 engine modification status records review
This review confirms that the modifications recorded on a CFM56 engine are embodied with the correct effectivity and backed by approval data. It is run by or for a lessor, airline, or asset manager evaluating or transferring a specific engine serial number. It checks Service Bulletin embodiment, STC files, configuration lists, and the approval basis behind each change. You receive a modification status view tied to source, an exception list for unsupported or mis-recorded changes, and a closure plan for the engine under review.
When this review is needed
- An engine's SB and STC status has to be confirmed embodied before a buyer prices the configuration.
- A mandatory Service Bulletin is claimed as accomplished and the embodiment evidence has to be located.
- An STC is recorded on the engine but its approval file has never been checked.
- Configuration has drifted across operators and no one has reconciled the modification status recently.
The problem
A CFM56 accumulates Service Bulletins and STCs across operators, and the modification status only holds if each change is embodied at the right effectivity and carries its approval data. A SB marked accomplished with no embodiment record, an STC with no approval file, or a modification recorded against effectivity that does not apply to this serial number leaves the status report asserting a configuration the evidence will not support.
What gets reviewed
- Service Bulletin embodiment checked against the recorded status
- STC files reconciled to their approval basis
- Configuration lists matched to the modifications actually embodied
- Effectivity on each modification confirmed against this serial number
- Approval data present for every recorded change
- Mandatory modifications reconciled to the AD position where they intersect
Scope this review
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What gets validated
- Each accomplished Service Bulletin carries embodiment evidence, not just a status line
- Every STC on the engine has a traceable approval file
- Modification effectivity applies to this serial number
- Configuration lists reconcile to the embodied modifications
- A modification that satisfies an AD is reflected consistently in the AD position
Evidence normally required
- The modification and STC status report for the engine serial number
- Service Bulletin embodiment records
- STC files and their approval data
- Configuration and effectivity lists for the engine
- The AD status where mandatory modifications intersect
Common discrepancies
- A Service Bulletin marked accomplished with no embodiment record behind it
- An STC recorded on the engine with no approval file on hand
- A modification recorded against effectivity that does not apply to this serial number
- A configuration list that does not reflect a modification embodied at a shop visit
What is at stake
A modification claimed without embodiment evidence can force the work to be redone or the status corrected before the engine transfers. An STC with no traceable approval may have to be removed or re-substantiated, and a change recorded against the wrong effectivity leaves the configuration in question at exactly the point a buyer is pricing it.
Move from findings to resolution
Move from findings to a documented resolution path.
How the work runs
Pull the claimed status
Assemble the SB and STC status the records assert for the engine serial number.
Confirm embodiment
Match each accomplished modification to its embodiment record and check the effectivity applies.
Trace the approvals
Verify each STC and modification carries approval data appropriate to the installation.
List the exceptions
Flag unsupported, mis-recorded, or misapplied changes and set the evidence needed.
What the buyer receives
- A modification status view tied to embodiment and approval evidence
- An exception list for unsupported, mis-recorded, or misapplied changes
- A closure plan naming the evidence needed for each open modification
Who uses the output
- Engineering deciding how to treat a modification with no traceable approval
- Asset managers pricing the engine against the configuration the records support
- Records teams assembling the modification evidence a buyer will require
How the work fits into the transaction or program
The modification review runs before a sale or a register change so unsupported changes are found while the shops that embodied them can still supply the evidence. Its exception list feeds the substantiation and status correction the transfer depends on, and it settles the configuration the rest of the file rests on.
Aircraft-specific considerations
CFM56 modification history builds up across many operators and a large installed base, so the same engine can carry SBs and STCs embodied under different authorities and revisions. The review is scoped to the specific serial number's effectivity, since a modification real on one engine may be recorded against a configuration that does not apply to the one under review.
Jurisdiction-specific considerations
An STC approved by the FAA is not automatically valid on an EASA register, so an engine crossing systems has its modifications checked against the approvals the receiving authority recognizes, and the review flags any change that would need validation or re-approval.
Regulatory limits
The review confirms that recorded modifications are embodied and supported by approval data. It does not approve a modification, grant or validate an STC, or determine that the engine is in an airworthy configuration.
What this review does not cover
- Developing, approving, or validating modification or STC data
- Embodying or removing any modification
- Any airworthiness determination on the installed configuration
Specific to this review
- Effectivity is where CFM56 modification records most often break: a change can be genuine but recorded against a serial number it does not apply to.
- An STC without a traceable approval file may have to be removed or re-substantiated, which is far costlier than confirming the basis before a transfer.
- A mandatory Service Bulletin that also closes an AD has to be consistent in both the modification and the AD records, and the two often disagree after a shop visit.
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). Type certificates, STCs (Subpart E), TSO authorizations (Subpart O), PMA (Subpart K), and export airworthiness approvals (Subpart L).
Federal Aviation Administration. STC application process, certification basis, and continued airworthiness obligations of an STC holder.
European Union / EASA. EASA design and production certification, STCs, ETSO authorizations, and EASA Form 1 release.
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.
Frequently asked questions
Why check embodiment if the status report already lists the modification as done?
The status line is the claim; the embodiment record is the proof. A buyer's diligence pulls the evidence behind mandatory modifications, so the review confirms each one is embodied at the right effectivity and approved before the claim is tested.
Relevant glossary terms
Related pages
Where this fits
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