AircraftOwner Online

While securing a field approval is not usually on an aircraft owner’s favorite-thing-to-do list, there are some changes in the works that should simplify the process, especially when it’s time to outfit your aircraft with equipment needed to leverage the exciting benefits of NextGen technology.

What Is a Field Approval?

A field approval is one way FAA approves the technical data for either a major alteration or major repair to a type-certificated product. The field-approval process provides a method to have acceptable data approved by the FAA to return-toservice a product after a major alteration or repair. The FAA Form 337 (or the electronic e 337) is used to document the details and approvals of a major alteration or repair. Once approved, the Form 337 becomes part of that particular altered or repaired product’s type design. An FAA aviation safety inspector (ASI) approves the acceptable data in block 8 by signing block 3 of the Form 337. This approval verifies the changes made to that particular product’s type design meet your aircraft’s certification requirements.

During the review process, an ASI may decide a field approval is not required. This may be because the ASI determined the repair or alteration to be minor or because FAA already approved previous data specific to this type of repair or alteration. Yet, a field approval can be denied, usually for not having all the necessary data to support the procedure or because, in the case of the alteration, the alteration exceeds the scope of a field approval and requires an amended type certificate (TC) or supplemental type certificate (STC). [See 14 CFR section 21.113]

With so many possible variations and combinations of aircraft and equipment, it’s not surprising how determining the need for a field approval can challenge even the savviest aviation maintenance technician (AMT). Contributing to the confusion has been a lack of details and standardization in some of the guidance materials. This is often compounded by the fact that policy changes have lengthy turnaround times, which in turn, makes keeping guidance up-to-date a constant challenge.

FAA has made some changes in the guidance that facilitate more efficient field approvals. “What we’ve developed,” says FAA Avionics Maintenance Branch Manager Tim Shaver, “is a checklist-type approach for evaluating an installation that stresses core items like electric load analysis and electromagnetic compatibility. By getting away from the specifics of each type of new technology and standardizing the common threads in these new systems, AMTs will be able to address the common factors on how to evaluate, as opposed to what to evaluate.”

Individual field-approval requests will continue to be evaluated on a case-by-case basis to ensure proper and consistent application of the approval criteria. This consistent approach is important. “Our goal is to help eliminate confusion often caused by having to analyze and compare installation requirements on a component-specific basis,” says Shaver.

Changes to the field-approval guidance are scheduled to be published in the Federal Register in about a year, along with a companion Advisory Circular (AC) update. And, to prepare the ASI workforce for this new change, a training course is scheduled to be available in summer 2010. The three-day avionics course is designed to allow ASIs to apply this information out in the field today before the scheduled implementation.

How Can I Increase My Field-Approval Chances?

Upcoming guidance will help streamline the process for field approvals, but here are some steps you can take now to help secure your chances of a successful approval request. “The most important step is to establish clear lines of communication with the FAA,” says Shaver. “Let the ASI assigned to your request know what you plan to do and provide as much specific information as possible.”

FAA recommends using a standard data package (SDP) that includes the following:

• Field-approval checklist (see Appendix 1 of AC 43-210)

• Data describing the alteration (drawings, photos, manuals, etc.)

• FAA Form 337 (paper or electronic)

Using this approach is not the only way to present data to the FAA, but it can be the fastest. You should also review FAA Order 8310.6 – Airworthiness Compliance Check Sheet Handbook. The order provides easy-to-review lists to help ensure that you address relevant certification rules and their means of compliance.

Working Together

FAA Program Manager Steve Thompson, who works with the Small Airplane Directorate, sees the field-approval process as a collaborative effort. “If you believe an engineer’s (see article on page 26, “When Engineers Get Involved in Field Approvals”) or ASI’s decision on your project is inconsistent with FAA regulations and policies, talk with the engineer or inspector about your concerns.” Thompson also suggests elevating your concerns up the chain of command if you are unable to resolve your concerns. “We know the approval processes may be frustrating at times,” says Thompson. “But we are committed to helping make the process as simple as possible.”

Tom Hoffmann is associate editor of FAA Safety Briefing. He is a commercial pilot and holds an A&P certificate