Modification & STC status
Pilatus PC-12 modification and STC status records review
This review confirms that the modifications, STCs, and service bulletins the records claim for a Pilatus PC-12 are recorded against the right serial-number effectivity and backed by approval data. It suits a buyer, lessor, or owner-manager who needs the configuration story to hold before a sale, an insurance review, or a program handover. The work checks the modification status report, STC files, and SB embodiment against the type design for the single-engine turboprop. You receive an exception list of unsupported or mis-effective changes, a source map tying each entry to its evidence, and a closure plan for the specific tail.
When this review is needed
- A PC-12 has passed through several owner-managers and its modification history was never reconciled to approval data.
- A buyer needs the STC and SB position confirmed before pricing a specific serial number.
- Mission equipment was fitted and the records do not show which STC or field approval covers it.
- The aircraft is moving onto a new program and the entry configuration must be settled first.
The problem
On an owner-managed PC-12 the modification record tends to grow by accretion: an avionics upgrade here, an interior change there, each signed off by a different shop and rarely reconciled against the type design. A modification can be physically embodied while its STC file or field-approval basis sits in a folder nobody kept, and effectivity is easy to record against a serial number the change never touched. The mismatch stays quiet until a buyer's technical team or an insurer asks for the paperwork.
What gets reviewed
- Embodied modifications and STCs checked against the recorded effectivity for this serial number
- Approval basis and substantiation data for each claimed change
- Service bulletin embodiment recorded at the correct revision and applicability
- Mission and avionics equipment changes tied to the STC or field approval that covers them
- Recorded configuration mapped to the type design and approved modification list
- Superseded or duplicated modification entries reconciled so the file reads consistently
Scope this review
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What gets validated
- Each recorded modification carries approval data appropriate to the installation and the jurisdiction of registry
- Effectivity on every embodied STC matches the airframe serial number and its build history
- Service bulletin entries cite the revision actually accomplished, not a later or earlier issue
- Mission-equipment installations reference a specific STC or field approval rather than a generic sign-off
- The recorded configuration reconciles to the type design without an unexplained change
Evidence normally required
- The modification status report and STC status list with effectivity
- STC certificates, field approvals, and their substantiation data
- Service bulletin embodiment records for the airframe and installed equipment
- The type-design and configuration reference for the PC-12 variant
- Work packages behind avionics and mission-equipment installations
Common discrepancies
- A modification recorded against effectivity that does not apply to this serial number
- Mission equipment embodied with no STC or field-approval reference on file
- An SB logged as complete at a revision the accomplishment record does not support
- Duplicate modification entries from two shops that describe the same change differently
What is at stake
A modification claimed without a traceable approval basis can force removal, re-substantiation, or a field-approval application on the new owner's clock. An SB recorded at the wrong revision leaves later applicability questions resting on a false premise, and a mission change with no STC reference can stall an insurance or lending decision until the basis is rebuilt.
Move from findings to resolution
Move from findings to a documented resolution path.
How the work runs
Assemble the claimed configuration
Pull the modification, STC, and SB status the records assert for this serial number.
Test effectivity and basis
Confirm each change applies to the tail and carries approval data valid for the registry.
Reconcile to the type design
Map the recorded configuration against the PC-12 build standard and approved modification list.
List and sequence exceptions
Flag unsupported or mis-effective changes and set the closure action for each.
What the buyer receives
- An exception list of unsupported, mis-effective, or unrecorded modifications
- A source map linking each modification and STC entry to its approval evidence
- A closure plan naming the document or action needed to settle each open change
Who uses the output
How the work fits into the transaction or program
The modification-status review sets the configuration baseline that AD applicability, weight-and-balance amendments, and equipment-list entries all lean on. Running it before a transaction or a program move means the recorded configuration is settled before anything else on the PC-12 is built on top of it.
Aircraft-specific considerations
PC-12 airframes are frequently owner-managed and fitted with mission-specific interiors, cargo doors, and avionics packages, so the modification file carries more field approvals and one-off STCs than a fleet-standard aircraft would. Because each owner tends to add equipment for a different role, the review scopes effectivity to the individual serial number and its build standard rather than a family template.
Jurisdiction-specific considerations
A PC-12 that will move between an FAA and an EASA register needs its STCs checked for validation or acceptance in the receiving system, because an approval basis recognized on one register is not automatically recognized on the other, and the review notes where a change will need a fresh acceptance path.
Regulatory limits
The review confirms that the recorded modification story is internally consistent and supported by approval data. It does not approve a modification, grant or validate an STC, or make an airworthiness determination on the installed configuration.
What this review does not cover
- A physical configuration survey of the aircraft
- Developing or approving new modification or field-approval data
- Any airworthiness determination on the embodied changes
Specific to this review
- Effectivity is the usual break point: a PC-12 modification can be genuine yet logged against a serial number the change never reached.
- Owner-managed PC-12s accumulate field approvals for mission equipment that a fleet operator would embody by fleet-wide STC, so the approval trail is more scattered.
- A modification with no traceable basis is far cheaper to resolve while the prior owner and installing shop are still reachable.
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
Does this tell us whether the aircraft is physically in the recorded configuration?
The review works from the records and the approval basis, confirming the modification story is consistent and supported. A physical configuration survey is a separate exercise and is often run alongside it when the airframe itself needs to be checked against the file.
Relevant glossary terms
Related pages
Where this fits
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