On the evening of May 6, 1937, Hindenburg, a German zeppelin and the largest airship ever built, caught fire and crashed to the ground in Lakehurst, New Jersey. The disaster claimed the lives of 36 people and dealt a devastating blow to the fledgling aviation industry. In the years since, the Hindenburg disaster has remained shrouded in mystery.
Investigators have long speculated about the cause of the fire, though a definitive answer has eluded them. But what are some of the possible explanations for why it happened?
Almost exactly a year before its famous demise, the Hindenburg made its first flight from Germany to the US. Indeed, the German dirigible’s fateful final journey was noteworthy for being the inaugural flight of its sophomore season. As such, it was the subject of considerable media attention, meaning plenty of news cameras were trained on the Hindenburg when it burst into flames and crashed to the ground. Spectacular images of the incident swiftly appeared on the front pages on newspapers around the world.
Perhaps encouraged by excitable media coverage of the disaster, it didn’t take long for sabotage theories to emerge. In the search for likely saboteurs, several key Hindenburg crew members picked out a prime candidate, a German passenger called Joseph Späh who had survived the crash thanks to his training as a vaudeville acrobat.
Having smashed a window with his film camera, Späh lowered himself out the window as the ground approached and hung onto the window ledge, letting go when the ship was 20 feet from the ground and applying his acrobatic instincts to execute a safety roll upon landing.
Späh aroused retrospective suspicion due to repeated trips into the ship’s interior to feed his dog. Crew members also recalled him making anti-Nazi jokes during the flight. Ultimately, an FBI investigation found no evidence of Späh having any connection to a sabotage plot.
Another sabotage hypothesis focused on a rigger, Erich Spehl, who died in the fire. A theory advanced by A. A. Hoehling in his 1962 book Who Destroyed the Hindenburg? centres on Spehl as the likely saboteur for a number of reasons, including reports that his girlfriend was a communist with anti-Nazi connections.
The fact that the fire originated in an area of the ship that was off limits to most crew members except for riggers like Spehl and rumours of a 1938 Gestapo investigation into Spehl’s involvement also figured in Hoehling’s hypothesis. More recent analysis of Hoehling’s theory has generally found evidence of Spehl’s involvement to be weak.
An accident waiting to happen?
Although sabotage can never be entirely ruled out, most experts now believe that the Hindenburg air disaster was most likely caused by a sequence of issues that were perfectly capable of bringing down an airship without skulduggery. The inherent risks of airship travel are obvious, as the airship historian Dan Grossmann has noted: “They are big, unwieldy and difficult to manage. They are very affected by the wind, and because they need to be light, they are also quite fragile. On top of that, most airships were inflated with hydrogen, which is a very dangerous and highly flammable substance.”
The Hindenburg disaster was such a public spectacle that it shattered confidence in airship travel in an instant, but in truth, with the emergence of safer, faster and more efficient airplanes, it was already on the way out.
According to both investigations at the time and more recent analysis, the most likely cause of the Hindenburg’s fiery demise was an electrostatic discharge (a spark) igniting leaked hydrogen.
A number of factors are thought to have conspired to trigger the blaze. Of course, the theory hinges on the presence of a hydrogen leak, which has never been proven, but investigators point to the difficulty the crew had in bringing the airship in trim prior to the landing as evidence of a potential hydrogen leak at the Hindenburg’s stern.
Rainy weather is thought to have played a part in the generation of an electrostatic spark, as did damp landing rope, which would have effectively ‘earthed’ the airship’s frame, but not its skin (the Hinderburg’s skin and frame were separated). This sudden potential difference between the ship’s skin and frame could have set off an electric spark, igniting the leaking hydrogen gas and rapidly engulfing the airship in flames.