**nothing gory, no footage of what happened after the collision, only video of what happened on-track is here** A lot of people know that this happened but don't necessarily know what exactly happened or much about it. Having been one of those persons, I recently watched a documentary about it and thought I'd share the story of what happened to cause the on-track accident. I made a gif of the on-track accident unfolding at various speeds. The footage was shot by a spectator who was there that day and ends when he stopped filming so that he could turn to run.
The 1955 24 Hours of Le Mans began on 11 June 1955; competition between Mercedes, Jaguar, Ferrari, Aston Marton, and Maserati was close and all fought for the top positions early on. The race was extremely fast, with lap records being repeatedly broken.
Coming into the pit straight at the end of Lap 35, Race leader Mike Hawthorn, in the Jaguar D-type, had just passed Lance Macklin's slower Austin Healy-100. After Passing Macklin, Hawthorn belatedly noticed a pit signal to stop for fuel. Hawthorn slowed suddenly in an effort to stop rather than make another lap and, owing to the Jag's disc brakes, slowed much faster than Macklin's Healy with drum brakes. As the pit lane was not separated from the rest of the race in these days, there was no separate pit lane entrance and Hawthorn was still directly in front of Macklin when he began to slow. Hawthorn's sudden and unexpected braking caused Macklin to slam on his brakes and momentarily lock them up as well (a small cloud of brake dust/tire smoke from Macklin's car is visible). Macklin, in an attempt to not hit Hawthorn and owing to his locked brakes, lost control momentarily and swerved across the center of the track.
While this was happening, Levegh, who was directly in front of the sister 300 SLR driven by Fangio, was quickly approaching Macklin and Hawthorn. Not wanting to slow down Fangio in the leading Mercedes, Levegh did not brake for Macklin's car, which though apparently back under control was now directly in front of Levegh and traveling much slower. Instead of braking in the little time that Levegh had to react, he tried to go around the outside of Macklin's car. Levegh, who was traveling at around 150 MPH, was not able to react in time and his Mercedes drove up the rounded, ramp-like back of Macklin's A-H 100 and thereafter became airborne.
Levegh's car landed atop the earthen embankment, which was the only thing separating the spectators from the track itself, and then went into the crowd. The car's continued somersaulting caused it to further disintegrate as it flung large and small pieces of itself through the massive crowd.
Though the actual amount is unknown, it is estimated that some 83 spectators and Levegh died that day, with an additional 120 spectators being injured. Below is the accident happening in close to real-time speed.