Waldo Waterman, pioneer (1909) west coast pilot, based 2-place Arrowbile design on 2 previous efforts: Whatsit, tailless plane of 1932, and Arrowbile, delivered Dept of Commerce 1935 as part of the "Safe Airplane" competition. Aerobile begun 1947 and fabricated from parts of the earlier designs. Completed 1957, test flown May 57. Engine mounted in rear of fuselage. Power can be transmitted to pusher prop or the 2 rear wheels. Prop not removed for ground operation. Tailless fuselage and quickly detachable wings allowed 3-min conversion from flying to road configuration. Ailerons and wing-tip rudders interconnected; turns made by turning wheel (no rudder pedals). 3-wheel (tricycle) landing gear configuration allowed registration as motorcycle in CA. Top speed about 70 mph on ground and 120 mph in air. Said that spins nearly impossible and very difficult to stall. One proposal was to sell car and rent wings at local airports. Span 38 ft; length 20 ft; height 8 ft 11 in; weight 1710 lbs.