ZEPPELIN

rigid airship of a type originally manufactured by Luftschiffsbau-Zeppelin and consisting of a cigar-shaped, trussed, and covered frame supported by internal gas cells. The first Zeppelin airship was designed by Ferdinand, Graf von Zeppelin, a retired German army officer, and made its initial flight from a floating hangar on Lake Constance, near Friedrichshafen, Ger., on July 2, 1900. Beneath the 420-foot (128-metre) craft a keellike structure connected two external cars, each of which contained a 16-horsepower engine geared to two propellers. A sliding weight secured to the keel afforded vertical control by raising or lowering the nose, while rudders were provided for horizontal control. The craft attained speeds approaching 20 miles per hour (32 km/h). During World War I the Germans achieved moderate success in long-range bombing operations with the zeppelin-type rigid airship, which could attain higher altitudes than the airplanes then available. On two occasions during 1917, German Zeppelins made flights of almost 100 hours' duration. Such performances led many people to believe that large airships would play a prominent part in aviation development. A number of Zeppelins were distributed to the Allied countries as a part of postwar reparations by Germany. Of many subsequent zeppelins, the two most famous were the Graf Zeppelin, completed in September 1928, and the giant Hindenburg, first flown in 1936. The Graf Zeppelin inaugurated transatlantic flight service, and by the time of its decommissioning in 1937 had made 590 flights, including 144 ocean crossings, and had flown more than 1,000,000 miles (1,600,000 km). In 1929 the craft covered about 21,500 miles (34,600 km) in a world flight that was completed in an elapsed time of approximately 21 days. The Hindenburg, 804 feet (245 metres) long, was powered by four 1,100-horsepower diesel engines, giving it a maximum speed of 84 miles per hour (135 km/h). In 1936 this airship carried a total of 1,002 passengers on 10 scheduled round trips between Germany and the United States. On May 6, 1937, while landing at Lakehurst, N.J., the hydrogen-inflated craft burst into flames and was completely destroyed, with a loss of 36 lives. The Zeppelin airship works were destroyed by Allied bombing during World War II, and building of the huge rigid airships was never resumed.