NTSB Cautions on Small Airplane Proposal

While the U.S. FAA’s proposed rewrite of small aircraft certification rules has gained wide support from industry, the NTSB is more cautious about the sweeping changes. The FAA in March released a notice of proposed rulemaking (NPRM) that would overhaul Part 23 certification standards, making them more performance-based and less prescriptive. It would enable use of international aviation community consensus standards, rather than be solely FAA-driven.

In comments on the NPRM, the NTSB said, “Although we appreciate that the NPRM attempts to address certain issues related to our safety recommendations and accident investigations, we are concerned with and have questions about how the new certification process will work. We urge the FAA to maintain the necessary level of safety as it continues to develop new pathways to airplane certification.”

The safety board noted that consensus standards have been used with light-sport aircraft, but investigations of in-flight structural breakups involving Zodiac CH-601XL light-sport aircraft revealed “problems, delays and omissions within the consensus standards,” according to the NTSB comments. Existing Part 23 regulations likely would not have allowed the certification of this aircraft design, the NTSB said, but ASTM consensus standards “did not provide adequate protection from catastrophic aerodynamic flutter.”.

While consensus standards provide a collaborative framework for standards development, the safety board added, “We are concerned that design standards important for safety considerations may be overlooked. We encourage the FAA to refine its methodology of how important design considerations are reviewed.”