for the £50,000 Kremer prize for human-powered flight, which had been on offer for 18 years. With Dr. Peter B.S. Lissaman, he created a human-powered aircraft, the Gossamer Condor. The Condor stayed aloft for seven minutes while it completed the required figure eight course, thereby winning the first Kremer prize in August 1977. The award-winning plane was constructed of aluminium tubing, plastic foam, piano wire, bicycle parts, and mylar foil for covering. Kremer then offered another £100,000 for the first human-powered crossing of the English Channel. MacCready took up the challenge and in 1979, he built the Condor's successor, the Gossamer Albatross, and won the second Kremer prize, successfully flying from England to France. He also received the Collier Trophy, which is awarded annually for the greatest achievement in aeronautics or astronautics, for his design and construction of the Albatross. He later created solar-powered aircraft such as the Gossamer Penguin and the Solar Challenger. He was involved in the development of NASA's solar-powered flying wings such as the Helios, which surpassed the SR-71's altitude records and could theoretically fly on Mars (where the atmosphere is thin and has little oxygen). MacCready also collaborated with General Motors on the design of the Sunraycer, a solar-powered car, and then on the EV-1 electric car. In 1985, he was commissioned to build a halfscale working replica of the pterosaur Quetzalcoatlus for the Smithsonian Institution, following a workshop in 1984, which concluded that such a replica was feasible. The completed remote-controlled flying reptile, with a wingspan of 18 feet, was filmed over Death Valley, California in 1986 for the Smithsonian's IMAX film On the Wing. It flew successfully several times before being severely damaged in a crash at an airshow at Andrews AFB in Maryland. The launch of the pterosaur model came off well but the radio transmitter link failed, perhaps because of the interference from some of the many base communications devices. The model nosed over and crashed at the runway side, breaking at the neck from the force of impact. MacCready helped to sponsor the Nissan Dempsey/MacCready Prize which has helped to motivate developments in racing-bicycle technology, applying aerodynamics and new materials to allow for faster human-powered vehicles. He was the founder (in 1971) and Chairman of AeroVironment Inc., a public company (AVAV) that develops unmanned surveillance aircraft and advance power systems. AV recently flew a prototype of the first airplane to