Effectivity error
Incorrect effectivity in aircraft modification and AD records
Incorrect effectivity means an airworthiness directive, service bulletin, or modification was recorded as applicable or not applicable on the wrong basis, so the compliance status does not match the aircraft's actual configuration. It is a problem for lessors, airlines, and MROs whenever the status list is rebuilt or reconciled. The check reads each item's effectivity against the airframe serial, part numbers, and embodied modifications. You receive a list of items applied or excluded in error and the corrected applicability.
When this review is needed
- A compliance status list is being rebuilt and each item's applicability must be tied to the actual configuration.
- An item is marked not applicable and the basis for the exclusion cannot be traced to a serial range or part number.
- A modification changed effectivity for downstream ADs and the dependent items were never re-evaluated.
The problem
Effectivity is set by serial range, part number, or prior modification, and it shifts as the aircraft is changed. An item carried forward from a fleet template, or an exclusion entered without checking the embodied configuration, can read as a clean status while masking a directive that actually applies. The status list then states compliance the configuration does not support.
What gets reviewed
- Each AD, SB, and modification by its stated effectivity basis
- The airframe serial, part numbers, and embodied modifications it is read against
- Items marked not applicable and the basis claimed for the exclusion
- Dependent items whose effectivity a prior modification altered
- Fleet-template entries carried onto the specific aircraft
Scope this review
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What gets validated
- Each item's applicability matches the airframe serial and embodied configuration
- Every not-applicable status traces to a serial range, part number, or modification basis
- Items whose effectivity depends on a prior modification reflect the embodied state
- Fleet-template applicability is reconciled to the specific aircraft, not assumed
- Open and closed status is consistent with the corrected applicability
Evidence normally required
Common discrepancies
- An AD marked not applicable with no traceable serial or part-number basis
- A service bulletin applied to a configuration it does not actually cover
- A dependent directive never re-evaluated after a modification changed its effectivity
- A fleet-template status copied onto an aircraft whose configuration differs
What is at stake
An item wrongly marked not applicable can hide an open requirement, while an item applied that does not belong inflates the work and confuses the status. Correcting effectivity often re-opens dependent items a prior modification changed, and at a transition an unverified effectivity basis blocks acceptance of the compliance status.
Move from findings to resolution
Sequence the fixes and the documentation that closes each finding.
How the work runs
Fix the configuration
Establish the airframe serial, part numbers, and embodied modifications the effectivity will be read against.
Test each applicability call
Compare every applied and not-applicable status to the configuration and the item's stated effectivity basis.
Trace the dependencies
Identify directives whose effectivity a prior modification changed and re-evaluate them against the embodied state.
Correct and register
Record the corrected applicability with its basis and list the dependent items the correction re-opens.
What the buyer receives
- A register of items applied or excluded on incorrect effectivity
- The corrected applicability with its serial or modification basis shown
- A list of dependent items re-opened by the correction
Who uses the output
- Continuing-airworthiness staff rebuilding the corrected compliance status
- Quality assurance confirming exclusions rest on a traceable basis
- Asset managers relying on a defensible compliance position at transition
How the work fits into the transaction or program
The review treats effectivity as its own failure mode within an AD and SB status check, so an item that is documented but applied to the wrong configuration is caught separately from one whose accomplishment evidence is missing. It feeds the corrected status list and the discrepancy register.
Aircraft-specific considerations
Effectivity granularity differs by type. On airframes with long production runs and many block changes, a directive can apply by line number or by a specific part fitted at build, so the check reads the build configuration of the individual tail rather than the model designation alone.
Jurisdiction-specific considerations
Equivalent directives can carry different effectivity in different authorities. Where the aircraft is moving registries, applicability is read against the receiving authority's directive set rather than assuming the prior authority's status transfers unchanged.
Regulatory limits
The review confirms whether applicability is set on a traceable basis consistent with the configuration. It does not determine compliance on the authority's behalf, grant an exclusion, or make an airworthiness determination.
What this review does not cover
- Determining compliance or granting an exclusion on the authority's behalf
- Accomplishing the directive or modification the effectivity governs
- Issuing any airworthiness determination on the corrected status
Specific to this review
- Effectivity is not static, because an embodied modification can pull an aircraft into or out of the applicability of later directives.
- A not-applicable status is treated as a claim requiring a serial or part-number basis, not as a neutral default.
- Fleet-template status lists are a frequent source of effectivity error, since template applicability is assumed rather than verified against the individual airframe.
Sources
U.S. Government (eCFR). The legal basis for issuing and enforcing Airworthiness Directives on U.S.-registered products.
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
Why treat a not-applicable status as something to verify?
A not-applicable entry is a positive claim that the item does not apply to this configuration. Without a traceable serial range, part number, or modification basis behind it, the exclusion can mask an open requirement, so it is checked rather than accepted as a default.
Relevant glossary terms
Related pages
Where this fits
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