What Is a Part 145 Repair Station? A Plain Guide for Aircraft Owners

You search for an aircraft maintenance shop. Many describe themselves as a "Part 145 repair station." What does that mean? And does it matter for you?

What Part 145 is

Part 145 is a section of the US Federal Aviation Regulations. It is Title 14 of the Code of Federal Regulations, Part 145. It sets the rules for repair stations. A repair station is a business that the FAA has approved to maintain, repair or alter aircraft and aircraft parts for other people.

The approval is a certificate. Each shop has its own certificate number and its own limits.

What a certificate shows

A Part 145 certificate shows that the FAA has checked the shop. The shop must have suitable facilities, tools, trained staff and a quality system. It must also keep records and follow a written manual.

It does not mean the shop is the best choice. It means it meets a legal standard.

Ratings: what the shop is allowed to work on

The certificate lists ratings. A rating tells you which type of work the shop may do. Common ratings include:

• Airframe. The structure of the aircraft.
• Powerplant. Engines.
• Propeller. Propellers.
• Radio. Communication and navigation equipment.
• Instrument. Cockpit instruments.
• Accessory. Parts such as pumps and starters.

Some shops have a limited rating. That means they can work only on a certain make, model or part. A shop may be excellent on one type and not approved on another. Always match the rating to your aircraft.

Part 145 shop vs an individual mechanic

In the US, a certificated mechanic can do a lot of maintenance on their own. You do not always need a repair station. A repair station is often the better choice for major work, for engine and propeller overhauls, and for avionics. It is also the usual choice for commercial operators.

Outside the US

Europe has a similar system. It is called Part-145 and is run by EASA. The approved company is called a maintenance organisation. The US and Europe have an agreement that lets approved shops work on each other's aircraft, within limits. If your aircraft is registered in another country, ask the shop what approvals it holds for that country.

What to check before you hire

1. Ask for the certificate number and the list of ratings.
2. Check that the ratings match your aircraft type.
3. Ask about experience with your type, not only the rating.
4. Ask about parts. Where do they buy them, and do they come with traceable paperwork?
5. Ask for a written estimate and how they handle extra findings.
6. Ask for typical turnaround time and what a delay would cost.

Our guide on how to choose an MRO goes deeper on picking a shop. If you are buying an aircraft, see the pre-purchase inspection guide. And if a shop needs a part fast, read about aircraft parts suppliers and AOG brokers.

Sources: FAA, 14 CFR Part 145 (ecfr.gov, faa.gov); EASA Part-145 (easa.europa.eu).

Looking for a repair station? Browse providers in our Maintenance directory.