As certification of the Leonardo AW609 civil tiltrotor appears to be nearing the finish line, the FAA today requested public comment on proposed certification criteria for the aircraft. The comment period closes July 10.
It appears the FAA intends to certify the AW609 as a special class aircraft under FAR 21.17 (b) and before issuing formal powered-lift airworthiness standards, the latter widely anticipated in 2024 and that will largely impact eVTOL aircraft. Ahead of that, the FAA is announcing applicable regulations and other airworthiness criteria developed specifically for the AW609 that include applicable parts of certification standards for both helicopters and fixed-wing aircraft under FAR Parts 23, 25, 27, 29, 31, 33, and 35.
According to the FAA, “The proposed certification basis incorporates by reference existing transport category airplane and rotorcraft standards, one normal category airplane standard, Category A rotorcraft standards, optional Category B rotorcraft standards, and criteria for operation under instrument flight rules. This certification basis is not established for flight-into-known-icing conditions.”
Additionally, the FAA will apply modifications of existing certification standards to the AW609 under the newly-designated “tiltrotor criteria.” This will combine elements of Parts 23, 25, and 29 “as the maximum weight of the Model AW609 exceeds the weight for normal-category rotorcraft and most Part 23 airplanes, but its passenger seating is less than that of a transport-category airplane or rotorcraft.” The FAA also developed tiltrotor criteria because "no existing standard captures the powered-lift's transitional flight modes.”
The AW609 first flew in 2003 and Leonardo formally applied for type certification in 2012. Since that time, it has received multiple extensions to complete the normal three-year type certification process.