The Hindenburg explosion, from Wikipedia.org
I saw an episode of “Secrets of the Dead” on PBS last weekend, called “What Happened to the Hindenburg?” It was very interesting. It’s the story of Dr. Addison Bain, a retired NASA scientist, researching the disaster. He knows it’s the cause of people’s fears of hydrogen as a potential fuel. He calls it “the fuel of the future”. The investigation that was conducted in the U.S. at the time blamed free hydrogen, presumably from a leak in one of the hydrogen cells in the ship, and possibly a static electricity discharge on the ship, for the explosion. Bain worked extensively with hydrogen during his tenure with NASA, and understands its properties. Something in the official story didn’t sit right with him. He presents a convincing case that hydrogen was not the initiator of the fire, but rather it was the doping mixture put on the outer skin of this particular airship.
According to Bain’s theory, a combination of chemistry, and the physics of electricity initiated the fire. It started with the skin, and spread to the hydrogen cells, which then caused the hydrogen to ignite. Bain likened the doping material used on the Hindenburg to solid rocket fuel, since it contained iron oxide and powdered aluminum, among other chemicals. Both of these metal compounds are used in the solid rocket boosters of the space shuttle. He coupled this with the weather conditions on the day of the landing. The atmosphere in the area was likely electrically charged, due to nearby thunderstorms, and a thunderstorm which had produced precipitation had just passed. He postulates that the airship frame, and the outer skin had become electrically charged. The outer skin was probably wet. Bain claims that the wetness caused the skin, which was made up of fabric panels and had been painted in the doping material, to be unevenly grounded when the landing lines were dropped in preparation for landing. The frame was designed to be grounded, because the engineers knew that it was possible it might become electrically charged in the atmosphere. Bain claims the engineers did not anticipate these conditions, however. The theory goes that some of the panels did not ground their static charge easily when the frame was grounded, due to some panels being wet, and others not. This created an uneven charge between these charged panels and the rest of the ship, which probably caused one or more of the panels to electrically discharge via. arcing, which would’ve produced a lot of heat, igniting the doping material on the panels. The fire started in the tail and made its way to the front of the ship in less than 1 minute.
As is documented in this article on Wikipedia, there are those who disagree with this theory, saying that the doping material, while combustive, doesn’t burn very long, and they estimate it would’ve taken an hour for the skin to burn from back to front. I haven’t read their work, but my guess is they’re just considering the skin by itself, not the hydrogen gas, which contributed to the fire after it started, according to Bain’s theory. As was documented in the show, an interesting twist emerged in Bain’s research. It turns out one of the Hindenburg’s engineers did a test on two small zeppelin models shortly after the disaster. One was fashioned after an earlier airship model, and one was modeled after the Hindenburg, using identical materials as were used on the full size ships. He made both airships wet, and caused them to become electrically charged, creating the conditions that he suspected existed at the time of the accident. He grounded both of them. The older model, which did not use the volatile doping material on its skin did nothing. The Hindenburg model immediately caught fire. This would seem to confirm Bain’s theory. The reason this test did not become known is that the Zeppelin company chose not to make it public. Bain offered up the idea that perhaps this was done for insurance reasons. It was less damaging to them to let hydrogen take the blame. The thing was, the airship industry died as a result. No one felt safe flying in them after this incident. It may have died anyway, because airplanes were beginning to take civilian passengers at this point. They provided faster transport.
But now the stakes have changed. Hydrogen offers the possibility of an alternative fuel source for electrically-powered and combustion powered machinery. Personally I don’t see hydrogen as a rosy scenario. It will hopefully allow us to be more fuel efficient, but I think people have misconceptions about where hydrogen for fuel comes from. All means of generating hydrogen involve using energy. Currently we can extract hydrogen from water, or crude oil. It’s my understanding that most of it now comes from oil, and currently, getting it from water uses up more energy than it creates. Any carbon-based material is a potential source of hydrogen. Anyone who has taken organic chemistry knows this.
Anyway, it was a fascinating story. I applaud Dr. Bain on his research. The debate on this is not over yet, but I find his research convincing.