Experimental Airworthiness: The certification process

The certification process

Let’s take a look at the background, progress, and current situation surrounding the use of an Experimental Airworthiness Certificate to authorize flight following installations of equipment as a part of the certification process of a Supplemental Type Certificate.

On April 23, 2002, the FAA issued Order 8130.29 to supersede policy memorandum 2000-03 issued March 28, 2000. The title of the new order is "Issuance of a Special Airworthiness Certificate for Show Compliance Flight Testing." Although subtle, one change stands out between the previous policy memo and the new order and leaves the industry in an unfortunate situation. The new order includes the following statement under the procedures section of the order:

FAA Order 8130.29 paragraph 6(e)(3)(a): "(a) The applicant must ensure the aircraft is in compliance with all of the airworthiness regulations for its current standard airworthiness certificate."

Some may look at this statement and think that it is simple to show the aircraft is eligible for its current standard airworthiness certificate. But the fact is, the person who needs to be satisfied is the FAA Safety Inspector or designee in charge of the issuance of an experimental certificate. In most cases, such satisfaction is no different than a complete re-certification or issuance of a standard airworthiness certificate under the requirements of FAA Order 8130.2. With this new order, we now must meet those requirements before the experimental certificate is issued rather than when the standard certificate is to be reinstated. But the issue is deeper than that.

In addition to this significant change, there are a few terms, both in the regulation, and in this new FAA Order that, left without further explanation, lead FAA field engineers and inspectors to request more from STC applicants than is required. Let’s look at the impact and the need to request further action by the FAA on this issue.

There are really two issues:

1. The FAA, with little or no matrix or guideline on what type of change should require a Show Compliance Flight Test, determines the need for a show compliance flight test vs. adequate ground testing.

2. The use of an Experimental Airworthiness Certificate for required Show Compliance test flights is "not appropriate" according to Amendment 21-21.

What requires a Show Compliance Flight Test?

As an industry we are involved in modifications of business and commercial aircraft ranging from minor installations to major design changes that encompass many areas of an aircraft. The modifications that are performed are nearly always tested in the air following the installation even though the modifications do not always require such flights. The purpose of a flight can vary but in most cases significant ground testing has been performed to demonstrate compliance and the purpose of the flight test is only to make minor adjustments or identify minor programming changes.

Even though the intent of the regulation (21.191 (b)) exempts most modifications that are performed due to lack of need to flight test that aircraft, the misinterpretation by the FAA, at the field level, has created a great deal of costly and unnecessary work.

The issue really is that many FAA field engineers believe that because the aircraft has been subject to the Supplemental Type Certificate (STC) process that it is not possible to "show compliance" sufficient to "approve for return to service," (thereby reinstating the current standard airworthiness certificate) until the aircraft has been test flown. It is obvious that in some cases, an operational flight test must be conducted in order to "show compliance". But 14 CFR Part 21 provides some guidance as to what type of change should warrant such a flight.