On May 6, 1937, the Hindenburg, a German rigid airship known as a zeppelin, suddenly erupted in flames as it neared its dock in New Jersey after completing a crossing of the Atlantic. The craft burned rapidly, collapsing in moments, leaving 36 people dead.
The Hindenburg stayed aloft thanks to hydrogen, a gas that burns readily. Helium would have provided a much safer alternative (these airships were indeed designed to operate with helium), but the United States, which controlled helium supplies, restricted exports to Nazi Germany under the 1927 Helium Control Act.
