Paul MacCready Paul B . MacCready , Jr . ( September 25 , 1925 - August 28 , 2007 ) was an American aeronautical engineer . He was the founder of AeroVironment and the designer of the human - powered aircraft that won the first Kremer prize . He devoted his life to developing more efficient transportation vehicles that could " Do more with less " . Biography . Born in New Haven , Connecticut to a medical family , MacCready was an inventor from an early age and won a national contest building a model flying machine at the age of 15 . MacCready graduated from Hopkins School in 1943 and then trained as a US Navy pilot before the end of World War II . He received a BS in physics from Yale University in 1947 , an MS in physics from Caltech in 1948 , and a PhD in aeronautics from Caltech in 1952 . In 1951 MacCready founded his first company , Meteorology Research Inc , to do atmospheric research . Some of MacCready ' s work as a graduate student involved cloud seeding . He started gliding after World War II and was a three - time winner ( 1948 , 1949 , 1953 ) of the Richard C . du Pont Memorial Trophy , awarded annually to the U . S . National Open Class Soaring Champion . In 1956 he became the first American pilot to become the World Soaring Champion . He devised the MacCready Theory on the correct speed to fly a glider depending on conditions and based on the glider ' s rate of sink at different air - speeds . Glider pilots still use the " MacCready speed ring " . With Dr . Peter B . S . Lissaman he created a human - powered aircraft , the " Gossamer Condor " , and thereby won the first Kremer prize in 1977 . The award - winning plane was built out of aluminium tubing , plastic foam , piano wire , bicycle parts , and mylar foil for covering . In 1979 , he built its successor , the " Gossamer Albatross " , which won the second Kremer prize for successfully flying from England to France . 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 dinosaur model came off well but the radio transmitter link failed , perhaps due to 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 be powered by hydrogen fuel cells , the Global Observer . MacCready died on August 28 , 2007 from metastatic melanoma .