Deferred maintenance
Boeing 787 family deferred-maintenance records review
This review examines the deferred-maintenance items carried on a specific Boeing 787 and confirms each one is opened, tracked, and cleared with the evidence the records claim. It is run by or for a lessor, airline, or manager who is pricing, transferring, or operating the tail and needs to know what is genuinely open. It walks the deferment log, the MEL and CDL categories cited, the interval driving each item, and the corrective entry that closed it. You receive a supported list of open and disputed deferrals, a map from each item to its source entry, and a plan to close the exceptions.
When this review is needed
- A 787 is coming off lease and the redelivery conditions cap how many deferrals may remain open.
- A buyer wants the real open-item count before the deferment log gets folded into day-one status.
- A deferral has been rolled forward several times and no one can point to why it is still open.
- The tail is changing operators and each MEL item has to be reconciled to the receiving program.
The problem
Deferred items are the part of a 787 file most likely to be optimistic. An entry says an item was cleared, but the corrective work order is missing, or a category B item has quietly outlived its interval through repeated re-deferral. The deferment log, the MEL, and the actual open discrepancies drift apart, and the person operating or acquiring the tail inherits whatever the paperwork actually supports rather than what it claims.
What gets reviewed
- Every open deferral traced to its originating discrepancy and MEL or CDL category
- The interval or calendar limit governing each item and its remaining margin
- Corrective action entries matched to the deferral they claim to clear
- Re-deferred items reviewed for whether the roll-forward was permissible
- Deferrals tied to a modification or system change rather than a simple defect
- The open-item count reconciled against the tail's live discrepancy status
Scope this review
Tell us the asset, the event, and the evidence in scope, and we will outline a focused first engagement.
Send a representative, redacted record set and we will scope the review.
What gets validated
- Each cleared deferral is supported by a corrective work order, not just a log annotation
- Every open item cites an MEL or CDL category the 787 minimum equipment list actually contains
- Re-deferred items stayed within the interval their category permits
- The deferment log agrees with the aircraft's current open discrepancy report
- Deferrals touching a software or configuration item reference the correct part number
Evidence normally required
- The deferred-maintenance log and current open discrepancy report
- The operator's approved MEL and the CDL for the 787 variant
- Corrective work orders and return-to-service entries for cleared items
- The technical log pages showing when each item was raised and re-deferred
- Any redelivery condition that sets a cap on open deferrals
Common discrepancies
- A deferral marked cleared with no corrective work order behind the entry
- A category B or C item re-deferred past the interval its category allows
- An open item citing an MEL reference that does not match the approved list
- A deferment log count that does not agree with the live discrepancy report
What is at stake
A deferral treated as closed when its clearing evidence is missing becomes an open airworthiness item the moment someone checks. Rolled-forward items that exceeded their MEL interval can force grounding or an unplanned dispatch decision, and at redelivery an uncounted open list can breach the lease conditions and stall the handover.
Move from findings to resolution
Move from findings to a documented resolution path.
How the work runs
Pull the open list
Assemble the deferment log and reconcile it against the tail's live open discrepancy report.
Trace each item
Link every deferral to its originating discrepancy, MEL or CDL category, and interval.
Test the clearances
Match cleared items to corrective work orders and check re-deferrals stayed inside their limits.
Report the exceptions
Deliver the supported open list, the source map, and a closure plan for the disputed items.
What the buyer receives
- A supported list of open, cleared, and disputed deferrals for the tail
- A source map linking each item to its discrepancy and corrective entry
- A closure plan sequencing the exceptions that must be resolved before handover
Who uses the output
- Asset managers pricing the open-item exposure carried on the aircraft
- Records teams reconciling the deferment log before a redelivery or induction
- Continuing-airworthiness staff deciding which open items must clear first
How the work fits into the transaction or program
The deferred-item picture feeds the wider records review and the redelivery binder. A clean open-item count lets the receiving operator plan its induction, and the closure plan hands the current owner a defined list to work before the aircraft changes hands.
Aircraft-specific considerations
On the 787 a deferral often reaches into the electrical and systems architecture rather than a simple line replaceable unit, so an open item can carry a software part number or a configuration reference that has to match the loaded standard. Composite structure also changes how a deferred repair is described, because the disposition points to substantiation data rather than a routine sheet-metal entry.
Jurisdiction-specific considerations
An FAA operator and an EASA operator apply their own approved MEL, so an item permissible under one approval may not be carried the same way under the other. The review notes where a deferral will need re-basing against the receiving operator's MEL rather than assuming the outgoing categorization carries across.
Regulatory limits
The review reports what the deferral records support and where they fall short. It does not make an airworthiness determination on any open item, authorize a dispatch, or approve the clearance of a deferral.
What this review does not cover
- Performing or signing off the corrective work behind any deferral
- Issuing an MEL dispatch decision on the aircraft
- Physical inspection of the systems referenced in the deferment log
Specific to this review
- Re-deferral is where the count goes wrong: an item legitimately opened can drift past its interval through routine roll-forwards that no one flags.
- A deferral log annotation is not clearance evidence; the corrective work order is what an auditor or receiving operator will actually ask for.
- 787 deferrals frequently involve a system whose behavior depends on a software load, so the open item cannot be read without the configuration standard fitted.
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.
International Civil Aviation Organization. International standards for aircraft operation, including maintenance program and recordkeeping expectations.
Frequently asked questions
Why does a cleared deferral still show up as an exception?
A log entry that says an item was cleared is not the same as the corrective work order that proves it. Where the clearing evidence is missing, the item is treated as open until the underlying record is produced, because that is how a receiving operator or auditor will read it.
Relevant glossary terms
Related pages
Where this fits
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