Part-145 Supplier Evaluation and the Approved Supplier List

Give each supplier decision a defined scope

An entry on an approved supplier list is useful only when the reader can tell what was evaluated: the supplier, site, parts or service, evidence and any limits. In this guide, the list records the maintenance organisation's own supplier acceptance decisions. It does not confer an authority approval on a supplier.

Supplier evaluation sits inside the incoming-acceptance procedure. It helps establish how the supplier protects the items and records it provides. Each delivery still needs the checks described in the receiving inspection guide.

Avioverse has two relevant checklists in its Audits library:

Both links open the Checklists tab in Audits. Choose Avioverse library and search for the checklist by its title. These are audit checklists; they are separate from the receiving and stores forms used for individual inspections.

Choose evidence and a proportionate review method

Start with the activity you intend to purchase. Identify the supplier and facility, the parts or materials, relevant certificates and their scope, and the period or sample to review. A general certificate is less useful than evidence tied to the work being evaluated.

GM3 145.A.42(b)(i)(a) identifies quality-system elements for initial and recurrent supplier evaluation. Point (b) allows suitable certification to officially recognised standards, covering those elements, to support acceptance. Its qualification is explicit:

Point (c) allows the evaluation method to depend on the type of component, the supplier's role and circumstances such as an aircraft being grounded. A questionnaire, desktop review of procedures or an on-site audit may be appropriate. Select the method that gives enough evidence for the decision and record what remains unverified. Do not treat an unanswered question as Not applicable merely because collecting the evidence is difficult.

For renewal, include what happened after the last evaluation: receiving discrepancies, rejected deliveries, relevant occurrence records and the supplier's responses. For an initial evaluation, say when that history is unavailable. The checklist asks whether the history was reviewed; a reported occurrence is not, by itself, proof that the review or quality system failed.

Why the supplier checklist asks what it asks

The 45 items turn the evaluation into evidence checks. Some follow the quality-system topics in GM3 145.A.42(b)(i)(a); others are practical criteria identified as good practice in the checklist. They are not 45 separate legal duties imposed on every supplier.

Identity, quality documentation and competence. Identity and certificate-scope checks establish who and what the decision covers. The practical review of controlled documentation helps locate the procedures being assessed. GM3 points (a)(1)–(2) address current regulations, specifications and standards, and personnel training and competence. Sample the working information and records used by the people handling the supplied items.

Purchasing, source traceability and inspection. GM3 points (a)(5)–(7) connect the source of received items, the documentation required on purchase and incoming inspection. Point (a)(13) addresses batch splitting and its documents. A useful sample follows an item from source through receipt and any split to dispatch. The checklist also examines outgoing inspection and holding items pending acceptance as practical controls; the incoming-inspection guidance alone does not prescribe every outgoing check.

Shelf life, electrostatic protection and storage. GM3 points (a)(3)–(4) and (a)(9)–(10) cover shelf life, handling electrostatic sensitive devices, storage, packing and shipping. The purpose is to preserve condition through the supplier's custody. The checklist examines expiry identification, environmental evidence and protection in transit. Apply the instructions relevant to the items rather than inventing one temperature or humidity limit. For a Part-145 organisation, 145.A.25(d) is the direct storage duty; for other suppliers, distinguish the agreed evaluation criterion from a rule applying to their own activity.

Measuring equipment. GM3 point (a)(8) covers storage, use and calibration of measuring equipment where required. The checklist tests responsibility, due dates, recall and the handling of overdue or out-of-tolerance equipment. Its traceability review supports 145.A.40(b) where Part-145 applies. That rule says an officially recognised standard; do not recast it as a universal requirement for one particular national traceability route.

Problem parts, notification and recall. GM3 points (a)(11)–(12) and (a)(14)–(16) cover suspected unapproved components, unsalvageable components, notification of shipped non-conforming items, recall and monitoring the quality system. The checklist asks whether the supplier can identify affected recipients and act on a problem. Its quarantine and disposition checks also use 145.A.42(c)(i) where applicable. The cited supplier guidance does not set a universal reporting deadline for suspected unapproved parts.

Sub-suppliers and follow-through. The checklist examines subcontracted functions, requirements passed to outside parties and evaluation records. These practical checks ask whether controls survive the handover. They do not assume that every sub-supplier is a Part-145 organisation or that every evaluation needs a visit. Access arrangements and a signed declaration help make the evidence reviewable, but a signature cannot settle a contradiction in the records. The final decision and next-review entries make the outcome usable by purchasing and stores.

Evaluate the laboratory against the tools you will send

The Calibration laboratory evaluation checklist starts with the proposed service: tool types, measurement ranges, methods, required accuracy and the facility or mobile service involved. It then compares that need with the evidence of capability and sample results.

This duty belongs to the Part-145 organisation using the equipment. The evaluation asks whether the laboratory's evidence can support it. Apply the duty directly to the laboratory only where it is relevant to activity within that laboratory's own Part-145 approval.

Why the laboratory checklist asks what it asks

Scope and claimed accreditation locate the evidence: issuer, entity, facility, validity, limitations and expiry if stated. The checklist can record accreditation, a relevant Part-145 approval and procedures, other evidence, or none. Those are different kinds of evidence. Check the actual scope against the proposed tools, ranges and methods; do not infer unlimited capability from a certificate heading or invent an expiry where none is stated.

Technical capability asks whether the laboratory can do this work at the intended location. For example, ExampleMRO might need a torque wrench calibrated over a particular range. Evidence for dimensional measuring tools alone would leave that requirement unanswered. The same review can help ExampleAir's CAMO and operations planners understand whether a proposed service can support the maintenance schedule; those planning roles do not decide the tool's technical suitability.

Sample-certificate identity and completeness connect a result to a provider, customer, location, individual tool, method and date. Certificate references, pages and attachments let the reviewer distinguish the complete record from an excerpt or replaced issue. These are practical evidence checks, not a certificate layout prescribed by 145.A.40(b).

Results and traceability show whether the evidence is usable for the intended work. Review results with units, deviation, tolerance, measurement uncertainty and relevant environmental conditions. Trace the standards used through the calibration record and supporting evidence. A general statement of traceability or an accreditation certificate alone does not establish that chain. The rule supplies the calibration, record and traceability duties; the checklist's detailed certificate fields help the reviewer assess them.

Access, declaration and decision record how the evidence was obtained and what the evaluator concluded. Unlike the supplier checklist's access-agreement and signed-declaration checks, the laboratory checklist allows access to be recorded as not requested and a declaration as unavailable, with the adequacy of other evidence assessed. Neither a visit nor a declaration is automatic proof of suitability. Record missing evidence, findings, permitted scope and conditions before concluding the review.

Keep the decision usable between evaluations

A practical supplier register can hold the supplier and site, accepted scope, evaluation reference, decision and restrictions, evidence expiry where stated, next evaluation date and earlier review triggers. Keep the actual evaluation date, next review and finding deadlines distinct. GM3 refers to recurrent evaluation without prescribing a universal interval; choose and record the basis for your next review.

Feed receipt problems back into that decision. If ExampleMRO repeatedly receives mixed batches with incomplete documents, the receiving records give the evaluator a concrete sample for the next review, or a reason to review sooner. For a laboratory, an adverse calibration result or a change of scope can similarly prompt an earlier review.

In Avioverse, Audits provides reusable checklists, audit runs, findings and PDF reports. A register can retain row history, file attachments and reminders before a due date. Record the supplier decision and any register update explicitly: completing an audit does not itself update a supplier record or close outstanding findings.

The tool-control guide covers calibration intervals and the tool register. Continue to parts storage for preservation after delivery.

Where to read it yourself

The regulatory and guidance basis is AMC1 and GM3 145.A.42(b)(i), with 145.A.25(d), 145.A.42(c)(i) and 145.A.40(b), in the EASA Easy Access Rules for Continuing Airworthiness, 2025-09-02 revision. The two Avioverse checklists distinguish these sources from their practical evaluation criteria.