Eighty years ago today, on October 10, 1933, a United Airlines Boeing 247 en route from Cleveland to Chicago, mysteriously exploded over Jackson Township, Indiana. The burning wreckage of the plane fell from the sky into a farmer’s field and nearby woods. All seven passengers and crew aboard the plane died. Witnesses on the ground reported seeing the aircraft explode and burst into flames before it came down.

This was the first fatal crash in the history of United Airlines. Air travel was so new that the flight didn’t even have a flight number; the registration number of the plane was NC13304. As officials investigated, it turned out that the crash of NC13304 was another grim first in aviation history: the first passenger plane to be destroyed in a terrorist attack. Forensic analysis of the wreckage showed that the Boeing 247 was destroyed by a nitroglycerin bomb planted somewhere aboard, probably in the lavatory.

But who did it? And why? The word “terrorism” was unknown in 1933, and before the crash of NC13304, a passenger plane had never before been downed by any form of intentional sabotage, much less a bomb. The paradigm, so familiar to us now, was unknown to investigators in the 1930s. At first the inquiry focused on a mysterious package wrapped in brown paper that someone observed one of the passengers carrying onto the plane. But when that package was found intact in the rubble, it was ruled out as the source of the bomb.

There were simply no clues. If any of the seven who died–including the first stewardess ever killed in the line of duty–had enemies, the police failed to identify them. Certainly no person or group claimed responsibility for the attack. (Terrorists didn’t really do that in 1933 anyway). Everything in the case was simply a dead end.

We do not know who bombed NC13304, or for what purpose. Eighty years later there’s little hope of a resolution in the case. This, the first act of terrorism directed against passengers traveling by air, remains one of the most mysterious.


The image of the Boeing 247, dressed in United Airlines colors from the early 1930s, comes from the Flickr collection of Tom Wigley, and is used under Creative Commons 2.0 (attribution) license.