CFM56 life-limited parts
CFM56 engine life-limited part traceability records review
This review confirms that the life-limited parts inside a CFM56 engine trace back to birth records and carry an unbroken cycle history. It is run by or for a lessor, airline, or asset manager evaluating or transferring a specific engine serial number. It checks each LLP against disk sheets, module build records, shop-visit releases, and the accumulated cycles on the current status sheet. You receive a per-part traceability map, an exception list for any break in the trace, and a closure plan tied to the engine under review.
When this review is needed
- An engine is being priced and its LLP remaining life drives most of the valuation.
- A shop visit built new modules and the disk sheets have to be reconciled to the current status sheet.
- An engine is coming off lease and the return conditions specify a back-to-birth trace on the disks.
- A serial number has passed through several operators and no one has confirmed the LLP history recently.
The problem
The cycle count that sets an engine's value lives on a status sheet, but the value only holds if every LLP behind that number traces to a release document and a birth record. On a CFM56 that has been through multiple shop visits, disks move between modules, and one missing disk sheet or a cycle figure that does not reconcile across a module build can undercut the whole position. Buyers pay for trace, not for the summary line.
What gets reviewed
- Each life-limited part matched to its birth record and current cycle count
- Disk sheets reconciled to the module build history for this serial number
- Cycle accumulation checked across every shop visit in the engine's life
- Release evidence confirmed for parts installed at the most recent build
- LLP status sheet cross-checked against the underlying part-by-part trace
- Any disk swapped between engines followed through its removal and installation records
Scope this review
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Send a representative, redacted record set and we will scope the review.
What gets validated
- Every LLP on the status sheet traces to a birth record, not to the summary alone
- Cycle totals reconcile across each module build and shop visit in the history
- A disk moved between engines carries removal and installation records at both ends
- Release documents match the part number and serial number recorded on the status sheet
- Remaining cycles stated on the status sheet agree with the accumulated cycles in the trace
Evidence normally required
- The current LLP status sheet for the engine serial number
- Disk sheets and birth records for each life-limited part
- Module build records and shop-visit releases across the engine's life
- Removal and installation history for any disk transferred between engines
- Cycle utilization records supporting the accumulated counts
Common discrepancies
- An LLP whose trace breaks at an early shop visit with no surviving disk sheet
- Cycle figures on the status sheet that do not reconcile to the module build records
- A disk installed at the last build with release evidence that names a different serial number
- A part swapped between engines with an installation record but no matching removal entry
What is at stake
An LLP with a broken trace is discounted to scrap value or held out of the sale until the missing document is recovered. If a disk sheet cannot be found and the cycles cannot be substantiated, the part is treated conservatively, and the owner carries the cost of a life that the records will not support.
Move from findings to resolution
Move from findings to a documented resolution path.
How the work runs
Rebuild the status sheet from source
List every LLP and pull its birth record, disk sheet, and installed-cycle figure from the underlying documents.
Reconcile across shop visits
Follow each part's cycles through every module build so the accumulated count agrees end to end.
Trace the transfers
Match removal and installation records for any disk that moved between engines or modules.
Flag and sequence gaps
List each break in trace and order the recovery by how retrievable the missing document is.
What the buyer receives
- A per-part LLP traceability map for the engine serial number
- An exception list flagging each break in trace with its location in the history
- A closure plan naming the document needed to substantiate each open part
Who uses the output
- Asset managers pricing the engine against LLP life the records actually support
- Records teams assembling the trace package a buyer will require at sale
- Fleet planners deciding which disks justify document recovery before a shop visit
How the work fits into the transaction or program
The trace review sits ahead of a sale, a lease return, or a shop induction, so the LLP position is settled before money or a redelivery condition rests on it. Its exception list feeds the recovery of missing disk sheets while the shops that built the modules can still be reached.
Aircraft-specific considerations
CFM56 disks migrate between engines and modules over a long service life, so the trace is followed part by part through each shop visit rather than read off the current status sheet. The large installed base means the same disk may carry a history across several operators, and the birth record often sits with a shop the current owner has never dealt with.
Jurisdiction-specific considerations
An engine moving between an FAA and an EASA register has to show LLP trace acceptable to the receiving authority, so the review notes where a release document satisfies one system but would need a dual-release counterpart for the other.
Regulatory limits
The review substantiates the recorded LLP trace against source documents. It does not set remaining life on an authority's behalf, certify a part, or determine that the engine is airworthy.
What this review does not cover
- Physical inspection or dimensional check of any disk
- Re-lifing a part or recalculating a published cycle limit
- Any airworthiness determination on the engine or its life-limited parts
Specific to this review
- The disk sheet, not the status sheet, is the document a buyer's diligence team will demand, because the summary can be right while the trace behind it is broken.
- A disk that has moved between engines is where the CFM56 trace most often breaks, since the removal and installation entries live in two different shop packages.
- Recovering an early disk sheet gets harder each year as the original build shop's retention lapses, so the exception list is sequenced by recoverability.
Sources
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.
Federal Aviation Administration. Completion and use of FAA Form 8130-3, Authorized Release Certificate, for new and used parts.
European Union / EASA. Continuing airworthiness, maintenance records, CAMO responsibilities, and the airworthiness review process in the EASA system.
Frequently asked questions
Isn't the LLP status sheet enough to prove remaining life?
The status sheet summarizes the position, but a buyer prices the trace behind it. This review confirms each part's cycles reconcile to its disk sheet and birth record, so the remaining life on the summary is one an auditor would accept.
Relevant glossary terms
Related pages
Where this fits
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