As investigators examine recovered wreckage of the EgyptAir plane for evidence of a bomb, they are commencing a ritual first performed 83 years ago after a United Airlines plane went down on a flight from Newark to Chicago.

FBI reports on the Oct. 10, 1933 crash outside Chesterton, Indiana record witnesses hearing an explosion “such as heard in a quarry or blowing stumps.” The tail section of the plane was found a half mile from the main body.

At the unprecedented prospect that a bomb had bought down an airliner, the FBI took the case. Celebrated G-Man Melvin Purvis set aside his hunt for Public Enemy Number One, John Dillinger.