Terrafugia, the Massachusetts-based company founded by graduates of the Massachusetts Institute of Technology, has secured FAA approval to increase the maximum weight of the street-legal Transition light sport aircraft, and to also increase its stall speed beyond normal LSA limits. AOPA supported the company’s request for exemption, noting overall safety benefits that come from the tradeoffs.

The FAA received 286 comments on the company’s 2014 exemption request, more than 90 percent of which supported increasing the Transition’s weight and stall speed to accommodate federal highway safety regulations in addition to FAA requirements.

“Exempting Terrafugia’s Transition from the arbitrary LSA weight limit will demonstrate the FAA’s willingness to move towards performance-based limitations,” the association noted in comments filed in January 2015. Terrafugia engineers needed to build a heavier aircraft in order to satisfy federal motor vehicle safety requirements, including protection of occupants in a crash. “Unfortunately, the unique nature of the Terrafugia Transition and limitations on maximum road dimensions eliminate the possibility of increasing the wing area to produce additional lift, thus the need for an increased stall speed. It should be noted that according to the petition, even at this increased stall speed, significant stall margin is available to pilots on landing and takeoff.”

The Transition will stall at 54 knots, and the FAA’s decision (posted June 17) will allow the Transition to be flown by a sport pilot and used for instruction by a sport pilot CFI. The FAA determined Terrafugia’s request was significantly different from those made by other manufacturers seeking an increase of the 1,320-pound LSA weight limit (1,430 pounds for amphibious aircraft), and that the company’s design and goals are consistent with the FAA goal of reducing general aviation injuries and fatalities by improving crash survival. The agency determined, based on comments received and its own research, that the Terrafugia design provides a level of safety superior to the mandated minimum LSA standards.

“The willingness of the FAA to consider safety-driven innovation in novel ways, as evidenced by both this Grant of Exemption and the Part 23 rulemaking that is currently underway, is critical to the advancement of the aviation industry,” Terrafugia CEO Carl Dietrich said in a June 21 press release. “We look forward to continuing to work with the FAA to develop products that increase both the safety and utility of personal aviation.”

The company, founded in 2006, aims to succeed where many have failed, creating an aircraft that is both legal to drive on public roads and commercially successful. Development of the next model, the TF-X, which will have vertical takeoff and landing capability thanks to rotating engine pods, is being tested using a remote-controlled scale model. The company received a Section 333 exemption to operate the model in December.

AOPA and industry leaders continue to press the FAA to complete the Part 23 reform process quickly in the interest of increased safety, cost reduction, and increased innovation, which are all among the much-anticipated benefits.