From Wikipedia
https://en.wikipedia.org/wiki/1979_Unit ... _Prix_West
"On Saturday morning, Jean-Pierre Jabouille had a driveshaft on his Renault break on the curving back "straight," flinging him into the wall at 180 mph. A badly sprained arm would keep him out of the race. Then, in the Sunday morning warmup, a stronger version of the driveshaft, produced by the team in the garage, broke on teammate René Arnoux's car. Rather than taking a chance on duplicating Jabouille's incident, the team withdrew their remaining car from the race, allowing Derek Daly's Ensign onto the starting grid."
http://www.mckleinimagedatabase.com/ima ... tp+008.jpg
To be more specific it was JPJ's right-side drive shaft that failed. I know because I was working a fire response position driver's-right on the "curving back straight" (positioned just on the other side of the K wall from the track). As his car approached me on that lap, I just got some kind of 'sixth-sense' feeling that something was not right (maybe it was a different heat signature, or ??). Anyway, I spontaneously ducked to my left just as the half-shaft broke and pitched the car towards me. In the time it took to duck and carry around to look down track over my left shoulder, he had hit the wall right were I was standing, spun 180 degrees across the track, pancaked the outside wall, and was just disappearing around the corner. His momentum carried him to the next flagging station, so I didn't even have to respond... I just helped clean up the track (and my shorts
).