FAA Accepts ASTM Standards, Clearing the Last Hurdle for MOSAIC

The Light Aircraft Manufacturers Association arrived at Oshkosh this week with the news homebuilders and light-aircraft makers have waited a decade to hear. The FAA has published in the Federal Register its Notice of Availability accepting the key American Society for Testing and Materials (ASTM) consensus standards that support the new Part 22 light-sport category under the Modernization of Special Airworthiness Certification rule, MOSAIC.

The practical effect is direct. Manufacturers can now declare compliance against accepted standards, and the FAA can issue airworthiness certificates for aircraft designed under the expanded rules. Part 22 takes effect July 24, and the acceptance of these standards is the piece that makes that date operational rather than symbolic.

The FAA acceptance covers four integration standards developed by the ASTM F37 Committee on Light-Sport Aircraft: F3815-26a for airplanes, F3836-26 for gliders, F3840-26 for powered lift, and F3841-26 for gyroplanes. These integration standards function as packages, each referencing a wide set of underlying functional standards that govern specific components such as structures, engines, and propellers. F3840-26 was written to address both powered lift and multicopters, but the FAA acceptance is at present limited to powered lift.

The agency also clarified several technical points in its filing. The F2839 compliance-audit standard remains optional, and the F3833 guide for computer-based control systems is offered for reference only. The FAA will maintain a repository of accepted Means of Compliance on its Light-Sport Category Aircraft page, and the public may comment through the Regulations.gov portal under Docket No. FAA-2026-6965 until August 17.

LAMA President and Board Chairman Scott Severen framed the moment plainly. “New more capable airplanes are on the way,” he said, crediting the ASTM F37 committee and the FAA for the effort. The association traces the origin of the work to its own advocacy beginning in 2014, on the tenth anniversary of the Sport Pilot and Light-Sport Aircraft rule.

More is coming. Power-parachute, weight-shift control, and helicopter integration were not part of this notice and are expected in the next Notice of Availability. Severen said FAA Order 8130.2M, the last document needed to implement the second MOSAIC effective date, is on track to publish soon. One point bears repeating for owners: every light-sport aircraft sold over the past 22 years remains fully valid to fly. MOSAIC enlarges the category; it does not touch the aircraft already in it.