On May 6, 1937 the Hindenburg, a German airship carrying 97 people, caught fire and went down in flames. It’s source for buoyancy, the upward force for flight, was hydrogen gas. Hydrogen is the lightest element, (lighter than helium), but since hydrogen is more reactive than helium, it made for a very dangerous outcome.
Hydrogen likes to combine with oxygen to make water. When it does, it releases a tremendous amount of energy. Here is what happened.