With the speed -- close to 225 mph during practice -- and a crowded 34-car field, a big worry was aggressive driving early in the 200-lap race.
Chaos started when two cars touched tires coming around turn 2 and almost no one had time to react.
Within seconds, several cars burst into flames and debris covered the track nearly halfway up the straightaway. Some points of impact were so devastating workers had to patch holes in the asphalt.
Video replays showed Wheldon's car turning over as it went airborne and sailed into what's called the catch fence, which sits over a barrier designed to give a bit when cars make contact. Rescue workers were at Wheldon's car quickly, some furiously waving for more help to get to the scene.
Chaos started when two cars touched tires coming around turn 2 and almost no one had time to react.
Within seconds, several cars burst into flames and debris covered the track nearly halfway up the straightaway. Some points of impact were so devastating workers had to patch holes in the asphalt.
Video replays showed Wheldon's car turning over as it went airborne and sailed into what's called the catch fence, which sits over a barrier designed to give a bit when cars make contact. Rescue workers were at Wheldon's car quickly, some furiously waving for more help to get to the scene.