JD Mc Duffies' death was the worst one that I've seen live, it was extremely violent. It caused significant changes to the track to slow the cars down to a somewhat sane speed.
McDuffie was involved in an accident on the fifth lap of the 1991 Budweiser At The Glen race at Watkins Glen International. On the straight between the Esses and the Loop-Chute, at 170 mph, McDuffie and Jimmy Means touched wheels. McDuffie's driver's side outer tie rod end dropped from the front wheel spindle, which caused him to lose control of the position of the right side tire/wheel. Further, the impact caused the front wheel assembly to completely fall off the car, starting a chain reaction that resulted in all of McDuffie's brakes failing.