Hydrogen blimps
Blimps are floating airships that get their lift from lighter-than-air gases. Helium is a good option, since it isn’t flammable, but early blimps often used hydrogen. The error of this choice was underlined in fiery, spectacular fashion with the Hindenburg disaster of May 6, 1937. The incident left 36 people dead and earned hydrogen blimps a spot on the list of world’s worst inventions.
