25 Mason Street,
Somerville, MA 02144
Dear Mr. Dietrich:
This is in response to your letter of August 29, 2006, in which you asked if the Transition roadable aircraft would be classified as a motor vehicle. As explained below, our answer is yes.
By way of background, the National Highway Traffic Safety Administration (NHTSA) has the authority under the National Traffic and Motor Vehicle Safety Act (Safety Act, 49 U.S.C. 30101 et seq.) to regulate motor vehicle safety. The Safety Act at 30102(a)(6) defines "motor vehicle" as:
A vehicle driven or drawn by mechanical power manufactured primarily for use on public streets, roads and highways, but does not include a vehicle operated only on a rail line.
In your letter, you state that the Transition is an airplane that is capable of folding its wings and driving down the road to the pilots home or destination. In addition, the illustrations you provide with your letter show the Transition driving on a public highway with other traffic. As it is both capable of and intended for use on the public streets, roads and highways (public roads), the Transition would be considered a motor vehicle and subject to the applicable safety regulations.
You indicate in your letter that you believe the Transition should not be considered a motor vehicle because motor vehicles are manufactured primarily for use on public streets, while on the typical trip of 350 miles a Transition would spend only 18% of its time on land, spending the rest of the time in the air. Thus, you claim that the Transition is manufactured primarily for flight and not primarily for use on public roads.
We take a broader interpretation of the word primarily. Whether a vehicle is a motor vehicle under the Vehicle Safety Act depends on its intended or likely use on the public roads, and not on whether use on public roads constitutes a majority of its operating time. The word primarily refers to use on public roadways as a primary purpose of the
vehicle, as opposed to on-road use that is merely incidental. It is clear from the design of the Transition and from your letter that the on-road use of the vehicle is one of the primary functions for which the vehicle was manufactured. As this vehicle will spend a substantial amount of time on public roads, and was manufactured to do so, NHTSA will consider the Transition a motor vehicle.
This vehicle is intended for use in two modes of transportation, i.e. highway and aviation. The statute excludes on those vehicles that are used exclusively on a rail line. When on the ground, the vehicle is driven by mechanical power and, unlike other vehicles capable of flight that are intended to be driven only on runways and taxiways, the primary purpose of this vehicles being driven is for use on public roads.
This interpretation is consistent with others issued by this office in the past. A February 16, 1982, letter to Mr. Roger Olander stated that a three-wheel flying car was a motor vehicle under the Safety Act. Our January 24, 2006, letter to Mr. Paul Larkin stated that an amphibious vehicle was considered a motor vehicle. Copies of these letters are enclosed.
If you have any additional questions, please contact Ari Scott of my staff at (202) 366-2992.
Anthony M. Cooke