The 33-year-old racer was a two-time Indy winner, including this year’s race.
Three other drivers, including championship contender Will Power, were hurt in the pileup during Lap 13.
Weldon was airlifted from the track to University Medical Center; about two hours later, his colleagues were told of his death.
“IndyCar is very sad to announce that Dan Wheldon has passed away from unsurvivable injuries,” IndyCar CEO Randy Bernard said. “Our thoughts and prayers are with his family today. IndyCar, its drivers and owners, have decided to end the race.”
In his honor, drivers took part in a five-lap salute around the oval.
IndyCar has not had a fatality since Paul Dana was killed at Homestead in 2006, during a crash in a morning warmup.
Sunday’s wreck left Townsend Bell upside down while smoldering cars and debris littered the track nearly halfway up the straightaway of the 1.5-mile oval.
The accident appeared to start when Wade Cunningham’s car swerved on the track and JR Hildebrand drove over the left rear of Cunningham’s car. Hildebrand appeared to go airborne, and Cunningham’s car shot up into the wall, setting off a chain reaction among the cars behind him.
Some of those cars slowed, others didn’t, and others spun in front of Wheldon and Power. There was so much chaos on the track it was hard to tell who was driving what car.
Power appeared to fly over Alex Lloyd’s car, rolling into the catchfence and landing on its right side. His in-car camera showed one of the front tires coming toward him in the cockpit.
Wheldon then appeared to drive over Paul Tracy’s car. Tracy seemed to be slowing but Weldon did not. He went airborne and spun into the fence.
The track was red-flagged following the accidents while crews worked on fences and removed smashed cars.
Wheldon started in the back of the pack but quickly worked his way through the 34-car field before the wreck.
Despite winning this year’s Indy 500, Wheldon couldn’t put together a full-time ride this season. He landed in Sunday’s race thanks to Bernard’s promotion that promised $5 million to any moonlighting driver who could win the IndyCar season finale at Vegas. Although there were no takers, Bernard refused to scrap the idea and Wheldon was declared eligible for the prize.
It was Wheldon’s 134th career start, but only the third of the season for the two-time Indianapolis 500 winner.
“It was like a movie scene which they try to make as gnarly as possible,” said Danica Patrick, making her final IndyCar start. “It was debris everywhere across the whole track, you could smell the smoke, you could see the billowing smoke on the back straight from the car. There was a chunk of fire that we were driving around. You could see cars scattered.
Drivers had been concerned about the high speeds at the track, where they were hitting nearly 225 mph during practice.
Their concerns became reality when contact on Turn 2 sent cars flying through the air, crashing into each other and into the outside wall and catch fence.
“I’ll tell you, I’ve never seen anything like it,” Ryan Briscoe said. “The debris we all had to drive through the lap later, it looked like a war scene from Terminator or something. I mean, there were just pieces of metal and car on fire in the middle of the track with no car attached to it and just debris everywhere. So it was scary, and your first thoughts are hoping that no one is hurt because there’s just stuff everywhere. Crazy.”
Also injured in the crash were Hildebrand and Pippa Mann. Both will remain in the hospital overnight. IndyCar said Mann was being treated for a burn to her right pinkie finger and will be released Monday morning, and Hildebrand was awake and alert but will be held overnight for further evaluation
The accident spoiled what Bernard had hoped would be a showcase event for the struggling IndyCar Series.
The second-year CEO worked the entire season on turning the finale into a spectacle, and said he’d offer his resignation to the IndyCar board of directors if ABC’s broadcast didn’t pull a .8 ranking. His goal was to improve upon last year’s season finale’s horrible television rating and give the series some momentum for what’s hoped to be a strong season in 2013 with the introduction of a new car and new manufacturers.
So Bernard poured everything into Las Vegas, renting the speedway from owner Bruton Smith and agreeing to promote the event himself. He landed enough sponsorship to at least break even on race, and the $5 million challenge bought him an enormous amount of publicity the entire year.
Bernard got the Las Vegas Strip to close to stage a parade of cars, hosted industry parties and a blackjack tournament all to boost interest in the race. He even got MGM Grand Resorts to offer a pair of tickets to anyone staying this weekend in one of the chain’s 14 properties.
But what was hoped to be a day of celebration quickly turned somber.