While the comment deadline is not until Aug. 20, the FAA’s proposed rewrite of repair station certification and classification requirements already is drawing concerns of “significant and potentially damaging” changes.

The agency on May 21 released a notice of proposed rulemaking (NPRM) that would reduce the number of repair station classifications from eight to five, eliminate limited ratings, clear up language about certification requirements and clarify definitions for repair station work for airlines.

It is the result of a more than two-decade effort to revamp repair station rules, an initiative that has been only partly successful. The FAA began looking at the issue in 1989, and in 2001 released final rules updating the Part 145 regulation that governs foreign and domestic companies that perform maintenance on U.S.-registered aircraft and engines.

In 2006, the agency followed with an NPRM to tackle repair station ratings and classes, along with imposing a quality system, but this generated so much opposition the NPRM was withdrawn.

That same opposition is now expected for this latest NPRM, and the Aircraft Electronics Association (AEA)–which represents many small electronics repair shops–already has issued warnings that the proposal “makes wholesale changes to the avionics industry with damaging and costly repercussions,” while the Aeronautical Repair Station Association (ARSA) is scrutinizing the proposal to make sure that it does not “create as many problems as it is trying to ‘fix.’”

A chief initial concern for both organizations surrounds language on housing requirements for certification.

As written, AEA groups worry that the FAA’s NPRM has the potential to jeopardize the growing practice of mobile repair work and satellite bases. “The proposal eliminates many of the currently utilized opportunities for mobile maintenance operations,” AEA says.

ARSA notes that language and other specifics that will require careful review. “There are proposals for permanent housing, satellite repair stations and working for air carriers that will take study to understand their pros and cons,” says the association’s Executive Director Sarah MacLeod.

In addition, MacLeod notes the FAA’s proposed rating system and capability lists “must be reviewed thoroughly to ensure the agency avoids past pitfalls and has truly established an easily understandable method for knowing the type of work performed by each repair station.”

The FAA, however, says the ratings system—which dates to the 1930s and 1940s—needs changes because it “is not dynamic” and does not address current technology or industry practices. The standards are not clear and have been inconsistently applied, it says, adding: “These failings have resulted in repair stations having a variety of ratings to perform the same work. This system is confusing to repair station operators and their customers.”

To resolve this, the FAA suggests the number of ratings be narrowed to include airframe, powerplant, propeller, component and specialized service. Limited ratings would be scrapped.

One notable difference from the 2006 NPRM is a capability-list requirement. The earlier document had called for a repair station to get FAA approval before it could change or add to a proposed required capability list, which proved to be one of the more controversial items in the ratings proposal. The new NPRM, however, does not call for a mandatory capability list, but would revise capability-list recording requirements for repair stations that use one.

“This is a potential marked change for repair stations with class ratings that do not currently have a capability list of the items they maintain,” the agency says.

Critics of the 2006 proposal also opposed measures to deny an application for a repair station certificate if the applicant previously had a certificate revoked or materially contributed to a certificate revocation action, but this has been retained by the agency, which argues that such requirements are necessary. “Denial is not automatic,” the agency notes, adding that applicants could appeal a rejection.

The FAA further clarifies certification requirements involving equipment, personnel, technical data and housing and facilities that must be in place for certification inspection or rating approval. The proposal states that “if a repair station does not permanently possess these items, it must be able to demonstrate to the FAA that it has made arrangements with another person to provide such items whenever they are needed to perform the work.”

The proposal further aims to clear up confusion surrounding regulations requiring repair stations working for an air carrier to follow the carrier’s “program and applicable sections of its maintenance manual.”

Repair stations have complained that the term “applicable sections” is subjective and vague.

This proposal, FAA says, would clarify that “the repair station must perform that work in accordance with the maintenance instructions provided by the air carrier or air operator.”

One other change between the proposal and the 2006 NPRM is the agency’s decision to leave out new quality system requirements. The FAA says it is working on a safety management system (SMS) proposal that should cover quality standards. The SMS proposal also could require changes to any quality standards the agency might propose, the FAA says, adding that this would not “be an efficient use of repair station resources based on the unknown differences that may arise.”

The FAA is providing for a two-year phase-in period for the new proposal, and estimates that the $14.5 million cost imposed on more than 5,000 repair station over the next 10 years is relatively small.