Design exemptions pave way for ‘roadable aircraft’

June 30, 2011

Terrafugia Chief Operating Officer Anna Mracek Dietrich discussed the future of the Transition roadable aircraft at AOPA Aviation Summit in 2010.

The National Highway Traffic Safety Administration (NHTSA) has granted Terrafugia’s petition for temporary exemption from four federal motor vehicle safety standards (FMVSS) requirements for the company’s Transition roadable aircraft or “flying car.”

In granting the petition, which AOPA supported last December in formal comments, the NHTSA agreed that Terrafugia has made good faith efforts to comply with the standards, but that compliance would cause the firm “substantial economic hardship.” The agency imposed stricter time limits than those sought by the company for two of the four individual exemption requests.

“Terrafugia is a new company, and the Transition is a unique, dual-purpose vehicle designed for both flying and driving,” the agency said in its June 29 decision. “Many of the impediments to compliance that Terrafugia has encountered are a direct result of the dual nature of the Transition, including the need to meet the strict weight requirements of an LSA (light sport aircraft). Despite these impediments, Terrafugia has devoted significant resources towards compliance, has attempted to mitigate the risks associated with noncompliance, and has developed a plan for full compliance with three of the four listed FMVSSs by the end of the requested three-year period.”

The unique nature of the roadable aircraft supported a public-interest rationale for the exemptions, the decision said. The potential for Terrafugia to become the source of up to 500 manufacturing, engineering, and support jobs by 2015, once the Transition goes into production, also carried weight during the agency’s review.

The NHTSA agreed with the position—emphasized by AOPA in its comments on the exemption request—that the Transition could enhance aviation safety by giving VFR-only pilots who are confronted with deteriorating weather the option to divert to the nearest airport and continue their travel by road. Public interest would be served by reducing VFR-into-IMC accidents, it said.

The NHTSA granted Terrafugia three-year exemptions from requirements for tire selection and rims for motor vehicles (FMVSS No. 110), and glazing materials (FMVSS No. 205). It granted one-year exemptions from requirements for occupant crash protection, specifically advanced air bags (FMVSS No. 208) and electronic stability control systems (FMVSS No. 126). The agency noted that granting shorter exemptions than those requested by the company, in the case of the one-year grants, did not preclude Terrafugia from applying for more time when those exemptions expire. The exemptions become effective June 1, 2012.

However, given the benefits of advanced air bag systems and the passage of time since the requirements were established, the NHTSA said it was re-examining its exemption policy, and had come to a “tentative” conclusion that cost alone may no longer justify exemption from the requirement.

“The costs of compliance with the advanced air bag requirements of FMVSS No. 208 are costs that all entrants to the U.S. automobile marketplace should expect to bear,” it said.

In a June 30 news release, Woburn, Mass.-based Terrafugia said the exemptions “pave the way for Terrafugia to begin deliveries once Terrafugia's rigorous Transition certification testing program is complete.”

The Transition’s dual uses as an aircraft and ground vehicle require application of FAA regulations and standards for LSA, and federal motor vehicle safety standards for automobiles.

Dan Namowitz

Dan Namowitz | Aviation Writer

Dan Namowitz is an aviation writer and flight instructor. He has been a pilot since 1985 and an instructor since 1990.