Modification and STC status
Bombardier CRJ family modification-status records review
This review confirms that the modifications a CRJ's records claim as embodied are supported by approval data and recorded against the effectivity that actually applies to the tail. It fits a team evaluating, transferring, or maintaining one serial number, and it works from that tail's modification status report rather than a family list. The work reconciles Service Bulletin embodiment and STC files to their approvals, checks configuration lists against the type design, and confirms each change was applicable to this aircraft. You receive an exception list of unsupported or mis-recorded modifications, a source map to each approval, and a closure plan for that airframe.
When this review is needed
- A CRJ's modification history has built up across operators and no one has reconciled it to approval data recently.
- An STC is claimed as embodied and its approval file has never been checked against the installation.
- A buyer needs the configuration confirmed before pricing the tail.
- A Service Bulletin is recorded as accomplished but its effectivity for this serial number is in doubt.
The problem
A CRJ that has passed through several operators carries a modification status report that is a summary of decades of changes, and summaries lose their basis over time. A Service Bulletin can be recorded as embodied against an effectivity that never covered this serial number, or an STC can be claimed with an approval file that was never transferred with the tail. The status reads settled while the approval data behind individual lines has quietly gone missing.
What gets reviewed
- Service Bulletin embodiment reconciled to the effectivity applicable to this serial number
- STC files matched to the approval that authorized each installation
- Configuration lists checked against the type design and approved modifications
- Approval and substantiation data confirmed retrievable for each embodied change
- Modifications recorded against a wrong or absent effectivity flagged as exceptions
- Interaction between overlapping modifications reviewed where one change affects another
Scope this review
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What gets validated
- Each embodied Service Bulletin applies to this serial number by its stated effectivity
- Every claimed STC carries an approval file appropriate to the installation and jurisdiction
- The configuration list reconciles to the type design and the approved modification set
- Substantiation data behind each change is retrievable, not merely referenced
- Overlapping modifications are compatible rather than mutually invalidating
Evidence normally required
- The modification and STC status report for the serial number
- Service Bulletin embodiment records with effectivity
- STC files and their approval documents
- Configuration and effectivity references for the aircraft
- Substantiation data for the embodied changes
Common discrepancies
- A Service Bulletin recorded as embodied against effectivity that excludes this serial number
- An STC claimed on the status report with no approval file in the transferred records
- A configuration list line that does not reconcile to the type design
- An embodied change whose substantiation data is referenced but not retrievable
What is at stake
A modification carried on the status report without traceable approval data can force removal or re-substantiation, which is expensive and can ground the tail. An STC claimed but unsupported undermines the configuration that AD applicability and equipment status are built on, and at a transaction it becomes a discount or a retrade once the buyer's team cannot find the basis.
Move from findings to resolution
Move from findings to a documented resolution path.
How the work runs
Pull the claimed set
Assemble the Service Bulletin and STC modifications the records assert for the serial number.
Test effectivity and basis
Confirm each change applies to this tail and carries retrievable approval data.
Reconcile to type design
Map the configuration list against the type design and approved modifications.
Flag the exceptions
List unsupported or mis-recorded changes and order them by pricing and configuration impact.
What the buyer receives
- An exception list of unsupported or mis-recorded modifications
- A source map from each modification to its approval and substantiation data
- A closure plan ordered by which modifications block pricing or configuration
Who uses the output
- Records teams fixing the modification baseline the rest of the file rests on
- Engineering deciding how to treat a modification with no traceable approval
- Asset and acquisition teams pricing the configuration the records actually support
How the work fits into the transaction or program
Modification status sets the configuration baseline that AD applicability and equipment status depend on, so this review often runs before those and hands its confirmed configuration to the equipment-list and weight-and-balance reviews. Its exception list feeds the remediation a data room or an induction needs before anything is built on the configuration.
Aircraft-specific considerations
CRJ variants within the family differ in effectivity, so a Service Bulletin correct for one CRJ model can be mis-applied to another, which is a frequent recording error on tails that changed operators. Cabin and avionics STCs accumulate on regional aircraft as operators refit interiors, and those are the modifications whose approval files are most often left behind at a handover.
Jurisdiction-specific considerations
An STC approved under the FAA is not automatically valid under EASA, so a CRJ moving between systems is checked for whether each modification's approval is recognized by the receiving authority, and changes that would need a validation or a fresh approval are flagged rather than assumed to carry across.
Regulatory limits
The review confirms the recorded modifications are supported and correctly recorded and lists what is not. It does not approve a modification, grant or validate an STC, or determine that the aircraft is in an airworthy configuration.
What this review does not cover
- Developing or approving new modification or STC data
- Validating an STC for a receiving authority
- Any airworthiness determination on the installed configuration
Specific to this review
- Effectivity is where CRJ modification records break most: a variant difference means a bulletin can be real yet recorded against a serial number it never covered.
- STC approval files are the records most often left behind at an operator change, which turns a claimed modification into an unsupported one.
- Overlapping modifications can invalidate each other, so a configuration is only settled once the interactions are checked, not the individual lines alone.
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
A modification shows on the status report. Isn't that enough to rely on it?
The status report is a claim, and a claim is only as good as the approval data behind it. A modification recorded without a retrievable approval may have to be removed or re-substantiated, so the review confirms the basis rather than accepting the report at face value.
Relevant glossary terms
Related pages
Where this fits
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