Airship

The German inventor, Count Ferdinand von Zeppelin took the guesswork out of airship aerodynamics by building a rigid structure of lightweight aluminum girders and rings that would hold the vessel's streamlined shape under varying atmospheric conditions. Unlike Du mont's single-unit envelope, Zeppelin incorporated a number of drum-shaped gasbags within compartments of the structure to maintain stabilization should one of the bags become punctured or deflate. The dirigible was then encapsulated by a fabric skin pulled tightly across its framework. Buoyancy was controlled by releasing water ballast to ascend or by slowly releasing the hydrogen gas through a venting system as the ship descended.

Zeppelin was among the first airship designers to realize, in practice, the functionality of greater size in The internal structure of an airship. Illustration by Hans & Cassidy. Courtesy of Gale Group.


lighter-than-air vessels. As he increased the surface area of the envelope, the volume increased by a greater proportion. Thus, a larger volume afforded better lift to raise the aluminum hull and maximized the dirigible's cargo carrying capacity. Airships like the Graf Zeppelin, the Hindenburg, and their American counterparts, the Macon and the Akron, reached lengths of up to 800 ft (244 m) with volume capacities nearing seven million cubic feet. Hydrogen was, in part, responsible for such engineering feats because it is the lightest gas known to man and it is inexpensive. Its major drawback, one that would virtually close the chapter on non-rigid airship aviation, was its flammability. While passenger quarters, cargo, and fuel could be secured to or stored within the dirigible's metal structure, its engines were housed independently and suspended to reduce the possibility of friction-caused ignition of the gas.

Little did English writer Horace Walpole know how closely he had prophesied the future of airships when, upon the launch of the Montgolfier balloon, he wrote, "I hope these new mechanic meteors will prove only playthings for the learned or the idle, and not be converted into engines of destruction..." While zeppelins, as they had become known, were initially put into commercial service, successfully completing nearly 1,600 flights in a four-year period, they were engaged in the service of Germany during World War I as giant bombers, raiding London itself in May of 1915. After the war, the rigid dirigible was employed as both a trans-Atlantic luxury liner and airborne aircraft carrier, but eventually fell out of favor after the Hindenburg disaster in Lakehurst, New Jersey, on May 6, 1937.