The Hindenburg zeppelin, a lighter-than-air flying ship, was lifted by hydrogen contained in latex cells that were further contained in long cotton bags. This highly flammable gas fueled the fire that destroyed the Hindenburg.
Originally, the Hindenburg was designed to use helium, a much rarer gas than hydrogen, because of safety concerns. However, the main source for helium was the United States, which refused to export it. The engineers of the Hindenburg were forced to redesign the ship to use much lighter and more common – but also highly flammable – hydrogen gas to give their zeppelin the appropriate lift. This proved to be a fatal decision on March 6, 1937, when the Hindenburg caught fire during landing in New Jersey, killing 36 people.