Modification status gap
Service-bulletin (SB) status mismatch
A service-bulletin status mismatch is a difference between what the status list says about a bulletin and what the aircraft's recorded configuration actually shows was embodied. It is a problem for lessors, airlines, and MROs before a return, a re-lease, or a configuration review. The check reconciles each bulletin's recorded status against its effectivity, the embodiment evidence, the revision incorporated, and any AD that drives it. You receive the bulletins whose status does not match the records, the embodiment evidence each needs, and the path to reconcile them.
When this review is needed
- A return condition lists bulletins that must be embodied and the status list disagrees with the configuration records.
- A re-lease requires a known modification baseline and the bulletin status cannot be reconciled to the embodiment evidence.
- A bulletin is recorded as embodied at a revision earlier than the one the records actually show was incorporated.
- A bulletin that a directive makes mandatory shows as not embodied while the related directive shows as closed.
The problem
Service-bulletin status is held in a modification list that records whether a bulletin is embodied, but the list and the configuration it claims to describe drift apart over an asset's life. A bulletin can read as incorporated when no embodiment work card exists, or as not applicable on a configuration its effectivity covers. Revisions complicate it further, since a bulletin embodied at an early revision can be carried in the list as fully complied with even though a later revision changed the work.
What gets reviewed
- Each service bulletin against its recorded status and the actual configuration
- Bulletin effectivity against the aircraft by part number, serial number, or modification state
- Embodiment evidence, including work cards and release entries, for each bulletin shown as incorporated
- The revision recorded as embodied against the revision the work evidence actually supports
- Bulletins linked to an AD or a mandatory modification and the status of the related directive
- Interaction between bulletins where one supersedes or depends on another
Scope this review
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What gets validated
- Each bulletin shown as embodied has embodiment evidence present in the records
- Bulletin effectivity matches the actual configuration rather than an assumed fleet baseline
- The recorded revision matches the revision the embodiment work evidence supports
- A bulletin made mandatory by a directive reconciles with that directive's status
- A superseded bulletin is recorded against the bulletin that replaced it
- The modification list reconciles with the source configuration and work records
Evidence normally required
- Service-bulletin and modification status list
- Configuration and modification records for the airframe, engines, and components
- Embodiment work cards and release entries for incorporated bulletins
- Bulletin effectivity and revision documentation
- AD status for directives that make a bulletin mandatory
Common discrepancies
- A bulletin recorded as embodied with no embodiment work card behind it
- A bulletin marked not applicable on a configuration its effectivity covers
- An embodiment recorded at an earlier revision than the one the work evidence shows
- A mandatory bulletin shown as not embodied while its driving directive shows as closed
- A superseded bulletin still carried as the active modification in the status list
What is at stake
A modification baseline that the records cannot support undermines a re-lease, since the next operator inherits a configuration that does not match the paperwork. Where a bulletin is made mandatory by a directive, a status mismatch can also hide an open compliance item, and the gap has to be reconciled before the configuration and the directive status can both be relied on.
Move from findings to resolution
Sequence the fixes and the documentation that closes each finding.
How the work runs
Map the modification list
Capture each service bulletin and its recorded status, effectivity, and revision from the modification list.
Confirm effectivity
Test each bulletin's applicability against the actual configuration rather than an assumed fleet baseline.
Match status to evidence
Reconcile each embodied status against its work card, release entry, and the revision the evidence supports.
Reconcile and register
Cross-check mandatory bulletins against their directives, resolve supersession, and register every mismatch with its evidence need.
What the buyer receives
- A register of bulletins whose recorded status does not match the records, with the mismatch stated
- The embodiment evidence each mismatched bulletin requires to be reconciled
- A reconciled modification baseline that ties the status list back to source configuration records
Who uses the output
- Records and continuing-airworthiness teams correcting the modification baseline
- Asset teams confirming the configuration before a re-lease or sale
- Engineering resolving how superseded or interacting bulletins are recorded
How the work fits into the transaction or program
The review reconciles the modification list against the configuration the records actually support, so the bulletin status reflects the asset rather than an assumed baseline. It connects to the AD closure review, since a bulletin made mandatory by a directive must reconcile with that directive, and it feeds the configuration baseline a transaction depends on.
Aircraft-specific considerations
Bulletin volume and supersession differ by aircraft family and age. An older type carries many revisions and superseded bulletins, so the reconciliation tracks the revision and supersession history for the specific type rather than treating the modification list as a flat record of compliance.
Jurisdiction-specific considerations
A bulletin voluntary in one system can be mandated by a directive in another. Where an aircraft crosses authorities, the bulletin status is read against the modifications the receiving registry requires, since a bulletin not mandatory for the prior operator may be a compliance item for the next.
Regulatory limits
The review confirms whether service-bulletin status is consistent with the embodiment evidence and effectivity. It does not embody a bulletin, approve a modification, make an airworthiness determination, or certify the configuration on the authority's behalf.
What this review does not cover
- Physical embodiment or inspection of any modification
- Approval of a modification or configuration change
- Any airworthiness determination or regulatory approval
Specific to this review
- A bulletin embodied at an early revision is frequently carried as fully complied with even when a later revision changed the work, so the recorded revision is checked against the work evidence.
- Effectivity, not the status list, decides whether a bulletin applies, so a not-applicable entry is verified against configuration rather than accepted.
- Where a directive makes a bulletin mandatory, the two records must agree, and a mismatch between them can hide an open compliance item.
- Supersession is tracked explicitly, because a status list that still shows a superseded bulletin as active misstates the modification baseline.
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). The legal basis for issuing and enforcing Airworthiness Directives on U.S.-registered products.
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. FAA guidance on making and keeping maintenance records and acceptable recordkeeping practices.
European Union / EASA. Continuing airworthiness, maintenance records, CAMO responsibilities, and the airworthiness review process in the EASA system.
Frequently asked questions
How is a service-bulletin status mismatch different from an unsupported AD closure?
An AD closure review tests whether a mandatory directive is backed by accomplishment evidence. A bulletin status review tests whether the recorded modification state matches the embodiment evidence and effectivity. Where a directive makes a bulletin mandatory, the two reviews meet and must agree.
Relevant glossary terms
Related pages
Where this fits
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