LEAP modification status
Modification-status records review for LEAP engine assets
This review confirms that the modification and STC status recorded on a specific LEAP engine matches the approvals and effectivity behind each change. It is run for a lessor, airline, or manager evaluating, transferring, or maintaining the engine, usually where SB embodiment and STC history have built up across operators. It works through the service-bulletin records, STC files, configuration lists, and approval data, tying each claimed change to its basis and its applicability. You receive a supported exception list, a source map per modification, and a closure plan for this engine.
When this review is needed
- A LEAP engine's SB and STC history has accumulated across operators and no one has reconciled it to the approvals.
- A modification is claimed embodied but the approval data or effectivity behind it was never confirmed.
- A buyer needs the modification status supported before pricing the engine's configuration.
- A service bulletin was recorded as embodied and the revision and applicability need checking against this serial number.
The problem
Modification status is where the recorded configuration and the engine's real build can drift apart. A LEAP engine carries service-bulletin embodiments and any STC modifications, and each one has to name the approval it rests on and the effectivity that makes it apply to this serial number. An SB logged as embodied at the wrong revision, or a modification whose approval file never followed the claim, leaves the status report asserting a configuration the records cannot fully support.
What gets reviewed
- Service-bulletin embodiments recorded with the correct revision and effectivity
- STC modifications tied to their approval files and applicability
- The configuration list reconciled to the embodiments and modifications it asserts
- Approval data confirmed present for each claimed change
- Modifications checked against the effectivity for this serial number
- Changes that alter the engine build recorded as modifications rather than routine work
Scope this review
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What gets validated
- Each SB embodiment names a revision and effectivity that apply to the serial number
- Every STC modification carries an approval file appropriate to the change and jurisdiction
- The configuration list reconciles to the embodiments and modifications on record
- Approval data is present and retrievable for each claimed change
- A change that altered the build is recorded as a modification rather than routine maintenance
Evidence normally required
Common discrepancies
What is at stake
A modification without traceable approval data can force removal, re-substantiation, or a stall in acceptance until the basis is rebuilt. An SB recorded against effectivity that does not apply to the serial number puts the whole configuration record in question, and at a transaction the buyer prices the configuration the records actually support rather than the one the report claims.
Move from findings to resolution
Move from findings to a documented resolution path.
How the work runs
Pull the claimed status
Assemble the SB embodiments and STC modifications the status report asserts.
Check basis and effectivity
Confirm each change carries approval data and applies to this serial number.
Reconcile the configuration
Map the configuration list against the embodiments and modifications on record.
List the exceptions
Flag changes that do not trace to approval or effectivity and the evidence needed.
What the buyer receives
Who uses the output
- Asset and acquisition teams pricing the configuration the records actually support
- Records teams assembling the approval evidence behind each embodied change
- Engineering deciding how to treat a modification with no traceable basis
How the work fits into the transaction or program
The modification-status review sets the configuration baseline that AD applicability and the engine's build records all depend on. It runs before that configuration feeds a transaction or a program transfer, so the status report a counterparty reads reflects a build each change can be traced to.
Aircraft-specific considerations
Because the LEAP is a newer engine, its modification history is dominated by service-bulletin embodiments recorded in digital configuration systems, with fewer STC modifications than an older engine carries. The review confirms that each embodiment's approval reference actually rode along with the digital record, since current configuration is a primary value driver on this family and drift there is what a buyer checks first.
Regulatory limits
The review confirms the modification status is internally consistent and supported by approval data and effectivity. It does not approve a modification, grant or endorse an STC, embody a service bulletin, or make an airworthiness determination on the configuration.
What this review does not cover
- Embodying a service bulletin or performing any modification
- Developing, approving, or endorsing STC or modification data
- Any airworthiness determination on the installed configuration
Specific to this review
- On a LEAP engine, service-bulletin revision control is the most common failure point, because a digital record can pin the revision at which an SB was logged rather than the one in force at embodiment.
- Effectivity is where a modification record breaks quietly: an SB can be genuinely embodied but logged against a serial number the effectivity does not cover.
- A build change captured as routine maintenance is harder to unwind than a missing approval, because the record itself mislabels the modification.
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
The status report shows the SB as embodied. Why check the revision and effectivity?
An embodiment logged at the wrong revision, or against effectivity that does not cover the serial number, records a configuration the engine may not actually be in. A buyer reconciles the report to the approval data and effectivity, so a mismatch there puts the whole configuration in question rather than just one line.
Relevant glossary terms
Related pages
Where this fits
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