Work in Progress: AC 43.13-2A

Because of the importance of approved data in repairs and alterations, Bill O’Brien is heading a committee to write a new AC on the subject. He lists who is involved and the deadlines, so if you have something to contribute you can.


Performing major repairs and major alterations are the bread and butter of any general aviation (GA) maintenance business. Every year thousands of major repairs and major alterations are performed on older GA aircraft and this kind of re-mod work keeps a lot of GA repair shops solidly in the black. The downside of this arrangement is you must have FAA approved data to perform this kind of work and approved data is not something you can pull out of your back pocket when you need it.

Time-Consuming Process

So for major repairs and alterations you have to get a FAA field approval for the “acceptable” data you do have. But as every mechanic knows just getting an FAA field approval eats up a very large part of the mechanic’s and FSDO inspector’s time each year. How large? On the average, FAA FSDO nationwide, process between 22,000 and 25,000 field approvals a year. If you figure a very conservative total time of six man-hours for each field approval (industry and FAA) we are looking at a minimum of 132,000 man-hours a year you and I have to spend to get the job done.

The vast majority or about 65 percent of these field approvals are avionics upgrade installations. Despite the fact the FAA does not charge for the approval, and each FSDO office tries to keep the paper moving, I still get complaints from mechanics that say getting a field approval at the local FSDO is a lot like getting an elephant pregnant. It’s done at a high level, accompanied with much screaming and yelling, and it takes 19 months to get any results. Five or six years ago, I would reluctantly agree with them, but things are changing to speed up the field approval process.

What’s Been Done So Far

The first major change to the data approval process was the major revision to Advisory Circular, AC 43. 13-1B Acceptable Techniques and Practices, Aircraft Inspection and Repair in 1998. On the signature page of the AC there is a statement, signed by the Flight Standards Service Director, to allow the mechanics to make the determination if any one of the 56 “acceptable” repairs to non-pressurized areas he or she is going to perform is “appropriate,” “applicable,” and “not contrary to the aircraft’s manufacturer instructions” then that “acceptable” repair listed in the AC, is considered “approved.” This was a major step to reduce the overall number of field approvals for major repairs.

The second major change to the field approval process was the publishing of AC 43-210 on Feb. 17, 2004. This AC standardized procedures for requesting field approval data for major repairs and major alterations. This was the very first AC in 55 years that actually described what a field approval was, and how to request one from your local FSDO. Up until then, how to get a field approval was privileged insider information, and success or failure hinged on knowing who the “easy” inspector was in the FSDO.

New This Year

On July 28, of this year, something really big happened that affected field approvals for major repairs. On that date, the FAA published FAA Notice 8300.119. Now for the non-bureaucratic folks out there, a Notice is FAA headquarters instructions that are given to the field inspector about a change of policy or some other semi-interesting stuff. Since a Notice usually has a one-year time limit it does not have the job impact that an FAA Order does. So the Notice slipped under most FAA inspectors’ radar screens, including my own. When I finally read the Notice; it blew my socks off!

The Notice was a joint association between the Aircraft Maintenance Division, AFS-300 and the Aircraft Certification Division, AIR-100 and it allowed a mechanic for the first time in history to use the “acceptable” airplane manufacturer’s repair data in his maintenance manuals as “approved” data for major repairs on Block 8 of the Form 337. The mechanic still has to use the same decision tree process as in AC 43.13-1B to ensure the repair data is “appropriate,” “applicable,” and “not contrary to the manufacturer instructions” before approving the airplane manufacturer manual data for the repair.

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