LZ 130 Graf Zeppelin - Design and Development

Design and Development

The Graf Zeppelin II was originally designed to be nearly identical to the Hindenburg, and use hydrogen as lifting gas. After the Hindenburg disaster, however, Hugo Eckener vowed never to use hydrogen alone in a passenger airship again. The only source of helium in large enough quantities was in the United States, so Eckener went to Washington, D.C. to lobby for helium for his airships. He visited President Roosevelt himself, who promised to supply helium, but only for peaceful purposes. After the annexation of Austria in March 1938, U.S. Secretary of the Interior Harold Ickes refused to supply helium, and the Graf Zeppelin II was ultimately filled with hydrogen.

The design of LZ-130 incorporated a few improvements over the design of the LZ 129 Hindenburg. Initially, the engine cars were designed to have same pusher configuration as the Hindenburg's, but as construction continued the engine pods were completely redesigned, using diesel engines powering tractor propellers. In later flights, the airship used three-bladed propellers on its rear engines; first installed on the aft-port engine car. Unlike the wooden propellers of the Hindenburg, which had problems with moisture absorption causing imbalance, these three-bladed propellers were made of plastic wood and individual blades were assembled onto a main hub. The engines had a water recovery system which captured the exhaust of the engines, recovering water vapor present in the exhaust gases and condensing it for storage in tanks aboard the airship, to compensate for the fuel's weight lost during flight.

Expecting helium to become available, the passenger decks were also completely redesigned to accommodate 40 passengers, compared to the Hindenburg's 72. The restaurant was moved to the middle of the quarters and the promenade windows were half a panel lower. The cabins would be more spacious and had better lighting compared to those of the Hindenburg; four of these were luxury cabins. The 16 gas cells were lightened and one was made of lightweight silk instead of cotton. The tail fins were slightly smaller and the rigging was redesigned. Other redesigns included the gas vent hoods, gondola and the landing wheel installation. On the nose cone there were just two windows, as with the Hindenburg's original design (in the Hindenburg more windows were later fitted after its test flights). The German investigation on the Hindenburg Disaster pointed to problems with conductivity on the Hindenburg's outer skin. As a result, the doping solution for the outer fabric covering was also changed, bronze and graphite were added to prevent flammability and also improved the outer covering's electrical conductivity. These changes were little-known and politically suppressed in fear of embarrassment for such a design flaw.