What a repair station is and what keeps its approval valid

01 Who approves a repair station, and what keeps that approval alive

A repair station certificate is the FAA's written answer to one question: may this shop legally return an aircraft, engine, propeller or article to service? The certificate names the ratings the shop holds, and the ratings decide what work it can sign off. A shop in Wichita and a shop in Miami can hold the same certificate number format and do completely different jobs, because the ratings are the real boundary. The Federal Aviation Administration's pages describe how the agency's certification work is organised, and the same logic of design review, testing and documented compliance runs through the shops as well as the factories.

Below is what the certificate contains, how the ratings split the work, and the conditions a shop has to keep meeting or the approval stops being valid.

02 The certificate is a list of ratings, not a licence to fix anything

When you read a repair station's approval, the honest way to read it is rating by rating. Each rating covers a category of work: airframes, powerplants, propellers, radios, instruments, accessories, and the specialised ratings that attach to particular processes rather than to a whole structure. A shop holding an airframe rating can work on structures and skin; it does not automatically get to open a turbine engine. That separation is deliberate, because the skills and the tooling are different, and the FAA certificate is built to match the skills that were actually inspected.

This matters when you are choosing where to send an aircraft. A shop with a long list of ratings is not automatically better than a shop with a short list; it is a shop that has been inspected against a wider set of capabilities. What you want to know is whether the specific job you need is inside a rating the shop holds. If it is not, the shop cannot issue the return-to-service record for that article, no matter how experienced its technicians are.

03 How does an approval stay in force once it is issued?

A repair station certificate is not a one-time award. It is kept alive by a continuing set of obligations: the shop must keep the facilities, equipment, personnel and inspection procedures that were part of its approval, and it must keep the records that show the work was done to the approved standard. The FAA's certification model, as the agency describes it, starts with a review of the design and the methods used to show compliance, then ground and flight tests, then an evaluation of the maintenance the product needs and whether it is suitable for service. Shops sit on the other end of that same chain: they are the point where continuing airworthiness is actually performed.

An approval is therefore a relationship, not a document in a drawer. The certificate identifies the holder and the ratings; the ongoing validity depends on the holder continuing to meet the requirements under which those ratings were granted. When the shop changes hands, moves to a new building, or changes the scope of what it does, the approval has to be looked at again, because the conditions that justified it have changed.

04 Where delegation comes into the picture

The FAA does not inspect every article itself. Federal law lets the agency delegate certain activities to a qualified individual or organisation, and those Organization Designation Authorizations, or ODAs, extend the reach of the certification process. The agency is explicit about the limit: it has never allowed companies to police themselves or self-certify their aircraft. The delegated unit works under FAA oversight, and the FAA states plainly that it stays directly involved in testing and certifying new and novel features and technologies through the Flight Standardization Board.

For a repair station the practical question is who signs. ODA unit members can be authorised to issue airworthiness certificates, and before issuing a standard or special airworthiness certificate, or a special flight permit, they must inspect the aircraft and document the inspection as set out in FAA Order 8130.2. Before issuing an experimental certificate or a special flight permit, the unit must get written FAA approval. Once a certificate is issued, the unit sends the certification package to the FAA. That paper trail is what makes a signature trustworthy later.

05 The September 2022 change you should know about

Delegation has been part of the safety system since the 1920s, and the agency argues it is what kept the country's aviation system from being stifled. But delegation only works if the people doing the delegated work can do it without pressure from their employer. In September 2022 the FAA strengthened its oversight of manufacturers authorised as ODA holders by protecting the industry employees who perform FAA functions from interference by employers.

The final policy requires ODA holders to monitor, report and investigate all allegations of interference, and to report the results to the FAA. It also sets a clear path for those employees to speak freely with FAA certification officials at any time, and they must be trained on the new policy. If you work in a shop under a delegated arrangement, that training and that reporting path are part of the conditions, not a courtesy.

06 What a documented inspection actually requires

The FAA's account of certification begins with a review of proposed designs and the methods that will be used to demonstrate compliance with the agency's regulations. The same shape appears at the shop: before you return an article to service you inspect it, and you record what you found. The agency describes ground tests and flight tests to demonstrate safe operation as part of the certification project, and an evaluation of the maintenance and operational suitability of the product. The maintenance side of that sequence is where the repair station does its work, and the records it keeps are the evidence that the article still conforms.

For a mechanic or a shop owner, the practical consequence is that inspection without documentation is not a completed approval. Anyone can look at a part; the certificate system depends on a recorded result that a later inspector, an operator or an FAA official can check. The repair-station ratings tell you what the shop is allowed to inspect; the records tell you what it actually did. Read the FAA's aircraft certification pages for more on how the FAA structures that whole chain.

An FAA aviation safety inspector assessing a repair station works against the ratings and the procedures that were approved, not against a general impression of competence. That is why the certificate lists capabilities rather than describing the shop as good or bad. The list is the standard.

07 When a certificate is amended or surrendered

Because the approval is tied to specific ratings and specific conditions, it does not simply persist forever unchanged. A shop that adds capability has to have the added capability evaluated before it appears on the certificate. A shop that stops doing a class of work may need the rating removed, because holding a rating implies the facilities and personnel for it are still in place. The agency's certification work is described as a review of the design and the methods of demonstrating compliance, which is a reminder that a certificate is a statement about a particular arrangement at a particular time.

Transfer of ownership is the case that catches people out. The approval belongs to the holder and to the conditions under which it was granted, so a change of control is exactly the moment to check whether the ratings still describe the operation. Buyers of repair businesses should treat the ratings list, the facilities and the records as one package, because the FAA does not treat them separately.

08 What the FAA does not publish about individual shops

The agency's certification pages describe the process, the delegation framework and the standards, and they give the Boeing 737 MAX as a worked example: the design had major changes from the 737 Next Generation, so the FAA issued an Amended Type Certificate, with certification taking roughly five years from Boeing's January 2012 application to completion in March 2017. Amended type certificates typically take three to five years, and a completely new type can take five to nine. A shop owner reading that should notice the pattern: the calendar follows the complexity of what has to be demonstrated, not the urgency of the customer.

The FAA's aircraft certification pages do not list repair station holders, their ratings or their addresses. When you need a specific shop's current approval, the place to look is the FAA's own records, not a summary page. The agency also published, in February 2024, the report of the Expert Review Panel that Congress required under Section 103 of the 2020 Aircraft Certification, Safety, and Accountability Act. The panel of 24 experts, drawn from NASA, the FAA, labor unions, independent engineering experts, air carriers, manufacturers with delegated authority, legal experts and academic institutions, began work in February 2023 and issued 53 recommendations for Boeing and the FAA. The FAA says it worked with Boeing on implementing those recommendations alongside the company's safety and quality plan prompted by the Alaska Airlines mid-exit door plug accident, and that specialists will keep monitoring progress through certification programs and system oversight.

Delegation is also described as similar to organisational programs used in Europe and other countries, which the agency says helps the United States maintain a level playing field with foreign competitors. For a repair station, that means the standard you work to is not a purely domestic invention; it is part of an international expectation about how aircraft are kept airworthy. If you are weighing whether a shop's approval covers a job, start with the ratings and the records, then check the FAA's own certification pages for how those ratings are granted and renewed.

About the FAA aircraft certification pages: faa.gov publishes how the FAA's Aircraft Certification Service oversees design, production, airworthiness certification and continued airworthiness for nearly all US civil aviation products, including large and small airplanes, rotorcraft, engines, propellers and foreign import products. The pages cover the certification process, Organization Designation Authorizations, the September 2022 interference policy and the Boeing 737 MAX certification timeline. The section does not publish individual repair station ratings or addresses.

09 Where to continue

The pages below take what a repair station is and what keeps its approval valid a step further inside operations and upkeep, beginning with What a Part 135 operator is and how it is structured, then move on to the next trade. Each one names the agency that holds the rule it describes.