Part 145 record-keeping for component shops: a practical guide

Part 145 record-keeping is the component shop’s responsibility alone. Under EASA 145.A.55, the three-year retention clock starts from the date of the certificate of release to service (CRS) — not from induction, not from the date work was completed. Here is what that means at the bench.

Why record-keeping liability lands harder on component shops

In an airline MRO, record gaps pass through multiple quality layers before they become a problem. In a small component shop, the chain is shorter. The authorized maintenance organization (AMO) issues the CRS, and whatever is in that record feeds directly into the operator’s M.A.305 continuing airworthiness file. If it’s wrong, the error travels with the component.

The liability is also personal. Authorization under EASA 145.A.35 is individual. A certifying staff member who signs the CRS owns the accuracy of the underlying record. If an audit asks for the component maintenance manual (CMM) revision used on a brake overhaul from 18 months ago and the work order doesn’t show it, the person who signed has no defence.

This is a Friday-afternoon problem more than a compliance-theory problem.

EASA vs. FAA: the retention minimums side by side

Both frameworks measure retention from the point of release, not from the start of work. The minimums differ, and for dual-approval shops the EASA standard is the safe floor to build around.

If your shop holds dual approvals, apply the EASA three-year standard across the board. Maintaining different retention periods by regulatory regime creates an audit risk that isn’t worth managing.

The work order: the legal spine of the CRS

The work order is not administrative overhead. It is the document that justifies every CRS signature. On the FAA side, 14 CFR 43.9 sets the minimum content: description of work performed, completion date, name of the person who did the work, and the signature and certificate number of the person approving return to service.

EASA goes further. AMC1 145.A.55(a)(3) (ED Decision 2022/011/R) requires maintenance records to reference the revision status of the data used — not just the manual title, the specific revision. In a wheel and brake shop, the task card or work order must cite the CMM chapter and revision number current on the date work was performed. If the revision cited was already superseded and the shop’s technical-data control process under 145.A.45 didn’t flag the update, you have a finding that can put the entire release in question.

The work order also functions as the linking document for everything else: incoming material certifications, the CRS number, and the certifying staff authorization reference all connect to it. The Part 145 workflow — receiving → preliminary inspection → work order → job tasks → EASA Form 1 / FAA 8130-3 release → shipping — generates a record at each stage, and the work order is the spine that holds them together.

Incoming material certifications: the overlooked third of the record

Every replacement part entering a job — a brake disc, an O-ring kit, a piston seal — arrives with a release certificate. That’s an EASA Form 1, an FAA Form 8130-3, or a certificate of conformity (C of C) depending on the source. These documents are part of the detailed maintenance record for that work order and must be retained for three years under EASA 145.A.55(c).

EASA FAQ #19042 confirms that the AMO does not need to forward these upstream certificates to the operator. But the shop must retain them, matched to the work order number. That distinction matters: these certs stay with you, not your customer, but they cannot live in a general filing bin with no job reference.

The practical risk of an unlinked cert is real. If an airworthiness directive (AD) is issued against a part number after release and you cannot demonstrate which batch or serial number went into which job, the operator may face re-overhaul. That cost traces back to your intake record. Assign incoming certs a work order sub-document reference at goods receipt — not at the point of use, when the paperwork window is already half-closed.

Shelf-life and consumable traceability

Seals, O-rings, greases, hydraulic fluids, and thread-locking compounds all carry shelf-life limits from the OEM through the CMM or the material specification. An expired consumable in the build record is an airworthiness nonconformance — not a paperwork issue. The distinction matters when explaining it to a certifying staff member who skipped the lot number field.

For every consumable used on a job, the work order must capture the lot number, the date of manufacture or cure date (for elastomers), the shelf-life expiry, and the quantity used — at the time of use. If an O-ring was installed six months ago and someone is reconstructing the cure date from memory during an audit, the record is already compromised.

The simplest format for a small shop is a shelf-life card or consumables log attached to the physical work order docket. Two minutes during the job; potentially an hour of reconstruction afterward — if reconstruction is even possible.

Serialised component tracking through overhaul

For life-limited or cycle-tracked components — wheel bearings, carbon brake heat packs, torque-limited fasteners — the work order must capture the part number (P/N), serial number (S/N), total accumulated life at induction, life consumed during this visit, and remaining life at release. All five values, not four.

Under EASA Part-M M.A.305(d), the operator’s continuing airworthiness record must show total time/cycles accumulated and remaining life to the applicable limit. The AMO’s CRS and work order are the primary source for that data. A transcription error in accumulated cycles on the CRS directly corrupts the operator’s M.A.305 file — and this is where component shops most often cause downstream compliance failures, not through bad maintenance but through inaccurate data on a release document.

EASA does not use the term “back-to-birth” in its regulations — the agency’s FAQ confirms this. The applicable requirements are M.A.305(d) and (e). What matters practically is that the chain of EASA Form 1s across successive overhaul events must be unbroken for life-limited parts. Each overhaul’s CRS becomes the next shop’s incoming documentation.

EASA Form 1 and FAA 8130-3: the record that leaves the shop

A component overhauled off-aircraft requires a CRS for the off-aircraft maintenance. If the same AMO then installs the component on the aircraft, a second CRS is required for the installation step — this follows from AMC2 145.A.50(d). Two releases, two documents, even when the same certifying staff member signs both.

For components maintained for the organization’s own use and not leaving the shop, an internal release (serviceable tag) may be acceptable if the maintenance organization exposition (MOE) provides for it. The moment a component goes to a customer, an EASA Form 1 is the standard. There is no grey area there.

The Form 1 number must appear in the work order record, and the work order number must be traceable from the Form 1. These are linked documents, not parallel ones. Treating them as separate generates the kind of finding that takes a full day to untangle during a surveillance audit.

Certifying staff records: the personal liability layer

Per AMC1 145.A.55(d) (ED Decision 2022/011/R), the minimum record per certifying staff or support staff member covers seven fields: name, date of birth, basic training, type training, experience, competency assessment, and scope of authorization. These records underpin the validity of every CRS signed. If a field is missing, every associated release becomes questionable.

In a small shop, the quality manager typically maintains these records and also verifies that each CRS was signed by someone whose authorization scope covers the specific component type on that release. A mis-scoped authorization is as bad as no authorization. The release is invalid either way.

Keep a live authorization matrix cross-referenced to MOE Chapter 6. Auditors check it against actual CRS samples. If the matrix is outdated, every release signed since the last update is a potential finding on a sample-basis review.

Tool calibration records: the silent work order dependency

EASA 145.A.40 requires measurement and test equipment used in maintenance to be calibrated and traceable to a national measurement standard, with calibration records maintained. Most shops comply on the calibration itself. Where they fall short is the link between calibration records and the work orders where those tools were used.

If a torque wrench or pressure gauge is found past its calibration due date, every work order where that tool was used since the last valid calibration may require review — potentially hundreds of records. One industry estimate, sourced from Oxmaint (a CMMS vendor, not a primary regulator), puts calibrated tooling found past its due date in approximately one in four Part-145 routine audits (Oxmaint, March 2026). Treat that as directional; the consequence matters more than the precise frequency.

The calibration record must cross-reference tool IDs and valid-from/to dates in a format that makes affected work orders searchable. Paper binders sorted by calibration date do not provide that capability, and discovering the gap during an audit is not the time to build it.

Digital records: what EASA actually permits

The EASA acceptable means of compliance (AMC) to 145.A.55 explicitly permits electronic records and electronic signatures. Three conditions apply: the signatory cannot repudiate the signature; access controls prevent unauthorized signing; and a full audit trail is generated. FAA AC 120-78A provides parallel guidance for electronic records under Part 145. Paper records remain legally acceptable under both frameworks.

From 22 February 2026, EASA 145.A.200A requires all Part-145 organizations to manage information security risks affecting aviation safety. This obligation, detailed in Commission Implementing Regulation (EU) 2023/203, Annex II (Part-IS.I.OR), covers every digital system storing maintenance records — regardless of shop size. The information security management system (ISMS) requirement applies now, not on your next renewal.

When evaluating shop management features for a Part 145 component shop, audit trail logging, role-based access control, and non-repudiable sign-off are regulatory requirements as of February 2026 — not differentiating extras. Build them into your evaluation before the deadline, not after.

What auditors actually look for: five recurring record failures

These findings appear consistently in component-shop audits. None are exotic. All are preventable with a well-structured work order and a consistent intake process.

• Work orders citing no CMM revision, or a revision that was superseded at the date of work and not caught by the shop’s technical-data control process.
• Incoming material certifications — EASA Form 1 tags, 8130-3s, C of Cs — not linked or filed against the relevant work order.
• Shelf-life consumable lot numbers and expiry dates not recorded at the time of use, making them unverifiable after the fact.
• Certifying staff authorization scope not covering the component type on the CRS that person signed.
• Calibration records not cross-referenced to tool IDs on the work orders where those tools were used.

Most shops that find these in a dry run had the underlying information somewhere. The problem was the filing, not the maintenance.

Practical record-keeping checklist for a component shop

Complete every item before closing the work order — not before signing the CRS, before closing the work order.

• Work order opened with P/N, S/N, and received condition documented.
• CMM chapter and revision cited for each task; revision confirmed current at the date of work.
• Task cards completed and signed by personnel whose authorization scope covers the component type.
• Incoming certifications (EASA Form 1, 8130-3, C of C) filed under work order number at goods receipt.
• Consumables logged at time of use: lot number, cure date or manufacture date, shelf-life expiry, quantity used.
• CRS number recorded in the work order; work order number traceable from the Form 1 or 8130-3.
• Certifying staff authorization reference noted in the work order record.

Retention trigger: the EASA three-year clock starts from the CRS issue date. The FAA two-year clock starts from the date the article was approved for return to service. Neither clock starts from induction or from the date work began.

Closure planning: document now where your records would transfer if the organization stopped operating. EASA 145.A.55(c) requires it, and it’s the first question any buyer or successor will ask.

Built on a real shop floor

AirOne MRO is developed inside a working EASA Part 145 wheel and brake shop. It is shop management software. The first 10 Founding Shops get a full year free in exchange for honest feedback.