First flown in October 2014, Slovakia’s AeroMobil 3.0 prototype converts from aircraft to car by folding the high-set wing back along the fuselage. A 100-hp Rotax 912 engine powers the front wheels in drive mode and a pusher propeller in fly mode. The AeroMobil is 29.5 ft. long, 7.35 ft. wide as a car, and has a 27.3 ft. span with wings unfolded.
As an aircraft, the AeroMobil’s minimum speed is 37 mph, takeoff 81 mph and maximum at least 124 mph. Air range is 435 mi. As a car, maximum speed is at least 99 mph, and range 545 mi. The wing has variable incidence to reduce takeoff roll to 540 ft., while rough-field suspension allows the aircraft to operate from grass strips.
Germany’s Carplane has twin hulls to improve drivability. Stowing the removable wings between the hulls prevents them from producing lift at higher road speeds, or forces from sidewinds if they were folded along the fuselage. Twin hulls allow use of four full-size, 15-in. car wheels while minimizing parasitic drag in flight. The Carplane is 17.8 ft. long and 7.4 ft. wide as a car, increasing to 24.5. ft. in length and 31.9 ft. in span with wings attached and tail extended.
A 150-hp snowmobile engine, modified for aircraft use by LSA Engines, is mounted between the hulls and drives the road wheels in car mode; the foldable pusher propeller in flight; and both the wheels and prop to increase acceleration on takeoff and shorten ground run to an estimated at 280 ft. Stall speed is 41 mph, cruise speed 125 mph and maximum road speed close to 110 mph. Carplane has built a prototype for ground testing initially.
A three-wheeler with tandem seating, the Netherlands’ Personal Air and Land Vehicle (PAL-V) is a gyrocopter in the air and a cross between motorcycle and car on the road. For flight, the rotor and propeller blades are unfolded, tail telescoped aft and rotor mast raised. The 230-hp engine spins the unpowered rotor up to 80% rpm before switching to the prop. This enables a 540 ft. takeoff ground roll.
On the road, the 13.1-ft.-long PAL-V One steers like a car, but banks like a motorcycle, with dynamic vehicle control adjusting the tilt angle in corners. The driver’s input is distributed between front-wheel steering and vehicle tilting based on speed and road conditions to maintain balance. Minimum flying speed is 31 mph. Maximum is 112 mph, in the air and on the ground; 0-60 mph is less than 8 sec. Range is 750 mi. on the road and up to 315 mi. in the air.
Samson Motor Works concept
Oregon-based Samson Motor Works’ Switchblade is a three-wheeler with side-by-side seating that is classed as a motorcycle on the road and will be sold in the U.S. as an amateur-built experimental aircraft. The wings fold forward under the body, where they are protected from damage by clamshell doors and a center keel. A “V-T tail” with twin rudders unfolds and deploys rearward, increasing length from 16.8 ft. in drive mode, to 20.2 ft. in fly mode. Width is 6 ft., and span 26.9 ft. with wings unfolded.
Samson Motor Works concept
A 180-hp Motus V4 motorcycle engine, already used in aircraft, powers a ducted propeller mounted between the rear drive wheels for protection. Samson has built a ground prototype to test the drivetrain and says the vehicle will be capable of 0-60 mph in under 7 sec. Top speed is expected to exceed 100 mph on the road and 160 mph in flight. Stall speed will be 67 mph. A flying prototype is being built.
The Transition is a four-wheeler with side-by-side seating for two. The wings fold up automatically against the fuselage. A 100-hp Rotax 912 engine powers the rear drive wheels, via a continuously variable transmission and a pusher propeller mounted between the twin tail booms. The Transition can cruise at 100 mph in the air and reach 65 mph on the road. Air range is 410 mi.
The Transition is 19.7 ft. long. Width is 7.5 ft. as a car, and span 26.5 ft. as an aircraft. Terrafugia plans to certify the Transition as a light sport aircraft (LSA) and has petitioned the FAA to raise the LSA limits to allow an 1,800-lb. gross weight and 54-kt. (62 mph) stall speed (versus 1,320 lb. and 45 kt.) because of the extra weight required to meet highway safety standards.
Flying cars have been a gleam in designers’ eyes since the early days of powered flight. None have ever been produced in any numbers, but there has been a renaissance of the concept. With several fly/drive vehicles in development, Aviation Week looks at some of the different ideas and styles.
Graham leads Aviation Week's coverage of technology, focusing on engineering and technology across the aerospace industry, with a special focus on identifying technologies of strategic importance to aviation, aerospace and defense.