354 FORMS OF ENERGY 1913 — At the beginning of World War I, France and Germany each possessed about 600 miHtary planes, and England 150. Top speed of airplanes was 126 miles per hour. Progress in aviation came to a standstill. Pusher-type airplanes with the propeller behind the pilot gave way to tractor planes with the propeller in front of the plane when it was found possible to synchronize the firing of a machine gun with the propeller. 1919 — Top speed of airplanes was 127 miles per hour. Lieutenant Commander Albert C. Read and his crew flew across the Atlantic Ocean in a flying boat of the American Navy. John Alcock and Arthur Brown made a nonstop flight of 1980 miles from Newfoundland to Ireland in 16 hours at a speed of 120 miles per hour. Ross Smith flew 14,000 miles from London to Australia in a series of hops. 1926 — Roman Franco flew from Spain to Buenos Aires; Richard Byrd and Floyd Bennett flew over the North Pole. 1927 — Francisco de Pinedo, an Italian, completed a well-planned trip that took him to Africa, South America, North America, and Europe, which demonstrated what scientific preparation and navigation can do. Charles A. Lindbergh flew from New York to Paris, a distance of 3325 miles, in 33}/^ hours. He depended upon dead reckoning for navigation. Perhaps no one in history ever received so many honors in such a brief space of time. Lieutenants Lester J, Maitland and Albert Hegenberger of the United States Army flew from the American mainland to Hawaii, guided by a radio beam. 1928 — Captain Kingsford-Smith and his crew flew the Southern Cross across the Pacific from San Francisco to Brisbane, Australia. Amelia Earhart, with W. Stultz and L. Gordon, was the first woman to cross the Atlantic Ocean in an airplane. 1929 — Rear Admiral Byrd flew over the South Pole. 1930 — Two Frenchmen, Dieudonne Costes and Maurice Bellonte made a nonstop trip from Paris to New York. 1931 — General Italo Balbo flew ten flying boats from Africa to Brazil. Post and Gatty flew around the world in 8 days and 15 hours. Boardman Polando flew from New York to Istanbul nonstop in 49 hours. 1932 — Amelia Earhart made a solo trip from Newfoundland to Ireland. 1933 — Wiley Post completed a solo flight around the world in 7 days, 18 hours, and 49}/^ minutes. 1937 — Three Russian airmen, Chkalov, Baidukov, and Beliakov, flew nonstop 5288 miles from Moscow, Russia, to Vancouver, British Columbia. Three other Russian airmen soon flew 6262 miles from Moscow to San Jacinto, California. 1938 — Howard Hughes and his crew flew around the world a distance of 14,672 miles in 3 days, 19 hours, 14 minutes, and 10 seconds. A German Heinkel fighting plane averaged 394 miles per hour. A Japanese plane flew 7240 miles nonstop with a crew of three. An Italian plane flew to an altitude of 56,046 feet. A 42-passenger airliner was launched.
AIRPLANE A TRIUMPH OF MODERN SCIENCE 355 1939 — Pan-American clippers inaugurated regular passenger service across the Atlantic Ocean and completed 100 trips on December 20, 1939. The first autogiro air-mail line was established between Camden airport and the Philadelphia post-office roof. Airlines carried 2,045,021 passengers 815,000,000 miles without a fatal accident. A German Messerschmitt attained an average speed of 469 miles per hour. 1940 — Stratosphere flights in airtight cabins were introduced by airlines. Land passenger planes of 25 tons and 4 engines were developed — their capacity is 42 passengers. Air service from the United States to New Zealand and Australia was inaugurated. Airplane engines of 2000 horsepower went into production. A patent was granted for retractable wing pontoons. Neoprene-rubber gasoline tanks became available. Airplanes enabled offensive warfare far to outstrip defensive warfare, in which little progress was made during the period 1918-1940. Airplanes were made which climb a mile per minute — Curtis Model 21-B. Fig. 148. A P-38 Lockheed interceptor plane which can leave the ground and climb a mile aloft in one minute. Recent tests indicated an airspeed of 458 miles an hour. (Courtesy of the U. S. Army Air Corps.) Many other noteworthy events in the history of aviation are omitted because of lack of space. This brief history of great flights is but the outward evidence of the tremendous advances made by the designers