March 4, 1936 marks the first flight of a true leviathan of the air. Hindenburg and its sister ship Graf Zeppelin were the largest aircraft ever to take to the skies. Unfortunately, Hindenburg is better known for its spectacular demise just over a year later.
Top: Hindenburg photographed in March, 1936. The name had not yet been applied to the zeppelin's skin Above: Hindenburg at Lakehurst, New Jersey, 1937
The Hindenburg, German dirigible LZ-129 (Luftschiff Zeppelin #129, registration D-LZ129) was a rigid airship, and the lead ship of the Hindenburg class. Designed and built by the Zeppelin Company (Luftschiffbau Zeppelin GmbH), and named after the late Field Marshal Paul von Hindenburg, the President of Germany from 1925-1934, Hindenburg was constructed of a duralumin frame and fitted with 16 cotton gas bags. The outer skin of the dirigible was made of cotton and covered with a reflective coating that was meant to protect the gas bags from ultraviolet and infrared radiation. Hindenburg was powered by four Daimler-Benz DB 602 diesel engines which produced 1200 hp each, giving it a top speed of 85 mph (135 km/h). Its first crossing of the Atlantic was completed in a record time of 64 hours, 40 minutes on May 6, 1936. Eastward transatlantic flights averaged around 55 hours.
Top: Hindenburg under construction in 1931; Above: Size of Hindenburg compared to some of the world's largest aircraft
Originally intended to be filled with helium, Hindenburg was instead filled with flammable hydrogen. At that time, helium was rare and came at an exorbitant cost. Even though the designers knew they would have trouble obtaining helium from the US, where it was a byproduct of natural gas mining, they went ahead with their plans to use it. When the US refused to lift the export ban on helium, the designers made the decision to switch to hydrogen. They were confident this wouldn't be a problem, as they had many years of safe, hydrogen-filled dirigible operations under their belt.
Hindenburg over Lakehurst, New Jersey in May, 1936. A Douglas RD-4 Spica of the US Coast Guard flies alongside, and the US Navy airship USS Los Angeles is moored in the background.
Hindenburg's final flight took place on May 6-7, 1937, a transatlantic crossing from Frankfurt to Lakehurst, New Jersey. It's arrival was initially delayed by a line of thunderstorms, but Hindenburg was finally cleared to land at about 7:00 pm. At 7:21 pm, shortly after dropping mooring lines to the ground crew, Hindenburg suddenly burst into flames and crashed. Within thirty seconds, Hindenburg had been reduced to a smoldering wreck of twisted, charred metal. Thirteen of the thirty-six passengers died, twenty-two of the crew of sixty-one perished, and one man on the ground was killed. The total cost was thirty-six lives.
The cause of the crash has been the topic of much conjecture, and no exact cause has ever been determined. Some suspect sabotage, other suggest atmospheric conditions. One of the more plausible theories is that hydrogen gas leaking from one of the cells was ignited by static electricity. In the British Pathé report below, the narrator points out how much water ballast Hindenburg is dumping. This may indicate a significant leak of hydrogen causing the airship to descend more rapidly than normal. After the crash, the duralumin hulk was returned to Germany and recycled for use in the construction of Luftwaffe aircraft. Graf Zeppelin was scrapped in 1940, its duralumin frame also going to support the war effort.