By JOHN MARSHALL

AP Sports Writer

LAS VEGAS — Every race car driver heads onto the track understanding this race could be the last and hoping it won't be.

On Sunday, IndyCar drivers got a harsh reminder when the worst happened to one of their own.

Two-time Indianapolis 500 winner Dan Wheldon died when his car got caught up in a 15-car pileup, sailed over another vehicle and smashed into a catch fence at IndyCar's season-ending race at Las Vegas Motor Speedway.

"Things happen in this kind of racing," said Wade Cunningham, also caught up in the wreck. "It's so close. Not much room for error. I was near the front of what caused all this, so I'm not thrilled about it. At this point, whose fault it was is kind of immaterial."

The green flag had barely stopped waving when disaster struck.

Wheldon, driving from the back of the field for a chance at $5 million, was moving through the pack when he drove into a tangle of cars careening off each other in every direction.

Unable to avoid the massive wreck unfolding before him, Wheldon clipped another car and went hurtling through the air, his car bursting into flames as it flew into a fence.

After just 11 laps, the race was over. Two hours later, track officials announced that Wheldon was dead. The Englishman was 33.

"One minute you're joking around at driver intros and the next, Dan's gone," said Dario Franchitti, whose wife, actress Ashley Judd, had to bring him a box of tissues. "I lost, we lost, a good friend. Everybody in the IndyCar series considered him a friend. He was such a good guy. He was a charmer."

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.

"It's unfortunate that early on in the race they've got to be racing so close. ...," Team Penske owner Roger Penske said. "You always worry about those at these mile-and-a-halves at the speed and with this many cars."

Three other drivers, including championship contender Will Power, were hurt in the pileup.

Wheldon was airlifted from the track to University Medical Center; news of his death came from IndyCar CEO Randy Bernard:

In his honor, drivers, many sobbing openly, took part in a five-lap salute around the 1.5-mile oval as thousands of fans stood and cheered from the grandstand.

Also injured in the crash were JR 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; Hildebrand was awake and alert but will be held overnight for further evaluation. Power was evaluated and released.

IndyCar has not had a fatality since Paul Dana was killed at Homestead in 2006 during a crash in a morning warmup. Wheldon won the race later that day.

Wheldon appeared to drive over a car driven by Paul Tracy, who seemed to be slowing down. Wheldon, however, went airborne and spun into the fence.

"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."

Wheldon, who came to the United States from England in 1999, won 16 times in his IndyCar career and was the series champion in 2005.

Despite winning this year's Indy 500, Wheldon couldn't put together a full-time ride this season but had a deal in the works for 2012.

Andretti Autosport, the team with which Wheldon won the 2005 Indy 500, had agreed to a contract early Sunday for Wheldon to replace Patrick next season. The deal was supposed to be signed after the race.

Wheldon landed in the Las Vegas race thanks to Bernard's promise of $5 million to any moonlighting driver who could win the IndyCar season finale.

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 would offer his resignation to the IndyCar board of directors if ABC's broadcast didn't pull a .8 ranking.

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, and the $5 million challenge bought him an enormous amount of publicity the entire year.

But what was hoped to be a day of celebration quickly turned somber.

When drivers returned to the track for the tribute laps, Wheldon's No. 77 was the only one on the towering scoreboard. Franchitti sobbed uncontrollably as he got back into his car for the memorial ride. The sound of "Danny Boy" echoed around the track, followed by "Amazing Grace." Hundreds of crew workers and representatives from each team stood at attention in honor of Wheldon.

"What can you say? We're going to miss him," Ganassi said. "Everybody in IndyCar died a little today."