James May drives and flies the Aerocar, a roadable aircraft, designed and built in the 1950s.

Aerocars can drive up to 60 miles per hour and have a top airspeed of 110 miles per hour. The Aerocar is a two-place aircraft with side-by-side seating, four wheels, high, unobtrusive wings, and a single Lycoming 0-320 engine mounted over the rear wheels. Conversion from air to road could be achieved by one person in five minutes. The detached aircraft components can be towed behind the car in folding wheels fitted to the wing roots. Civil certification was gained in 1956, but only six examples were built, with one still flying as of 2012. It initially sold for $25,000. The six Aerocars so far built accumulated over 200,000 road miles and 5,000 flight hours.    Specifications: Length: 21 ft 6 in (6.55 m) Wingspan: 34 ft 0 in (10.36 m) Powerplant: Lycoming O-320 air-cooled flat-four, 143 hp Maximum speed: 117 mph (188 km/h) Cruise speed: 97 mph (156 km/h) Takeoff speed: 55 mph (80 km/h) Range: 300 mi (483 km) Service ceiling: 12,000 ft   From: James May's "Big Idea" on BBC2 (Sep 28, 2008)