Wheldon, who won the Indy 500 in 2005 and 2011, was driving one of 15 cars involved in a fiery massive crash between Turns 1 and 2. His car went airborne and flew high into the fence before landing upside down on the edge of the wall. Wheldon's helmet hit the wall, causing an "unsurvivable head injury," said IndyCar CEO Randy Bernard, who announced Wheldon's death, at 33, just after 6 p.m. ET.
The impact was so severe the roll hoop broke off the top of his car. Wheldon was unconscious when safety workers arrived at the scene of his crash. A yellow tarp was quickly placed over his car to block the others from seeing the damage inside his cockpit.
The red flag was displayed by IndyCar Series officials, stopping the race. The remaining drivers later attended a meeting, where the decision was made to end the race. Approximately 10 minutes after that gathering concluded, they climbed into their cars and formed rows of three on the racetrack for a five-lap tribute to Wheldon. Crew members of every team, along with series officials, lined the edge of pit road as spectators stood politely and applauded on each of the five laps.
GALLERY: Remembering Dan Wheldon
Amazing Grace and Danny Boy were played in a solemn tribute to the likable driver from Emberton, England, who earlier in the day had agreed to a full-time ride with team owner Michael Andretti for the 2012 season, to replace the departing Danica Patrick. Wheldon is survived by his wife, Susie, and two sons, Sebastian, 2, and Oliver, 7 months. They were at the race along with other family members.
As Dario Franchitti pulled into the pit area, his wife, actress Ashley Judd, awaited the driver on pit road. She pulled a floppy sun hat over her eyes to hide some of the tears. When Franchitti climbed out of the car, they hugged. Then Franchitti hugged his father, George, as both men broke down in tears. He then turned back to Judd and they shared a tearful embrace. Franchitti called Wheldon one of his best friends.
The 2011 Championships Celebration, an awards banquet, was scheduled to follow the race on Monday night at Las Vegas' Mandalay Bay Resort & Casino, but IndyCar officials announced late Sunday that the event had been canceled.
A public memorial for Wheldon will be held at a later date.
In a cruel twist of irony, the accident was grimly reminiscent of a championship battle Franchitti was involved in back in 1999. On that day, his best friend, Greg Moore, was killed in virtually the same type of impact in a single-car crash on Lap 10 in the final race of the season. Moore's father, Ric, was at Sunday's race, his first time attending an IndyCar race since his son was killed 12 years ago.
Franchitti finished second in that's year's championship and won this year's over Will Power, but he had no reason to celebrate.
"One minute you're joking around during driver intros and then the next moment Dan's gone," Franchitti said. "I told [Dan's 2-year-old son] Sebastian Thursday night at the parade, that I've known his dad since he was your size. Dan was 6 years old when I met him. ... [E]veryone in the IZOD IndyCar Series considered Dan a friend. He was just one of those special, special people. I'm trying to hold it together."
Wheldon entered the 2011 season without a full-time ride. He agreed to a one-race deal with his friend, Bryan Herta, for the 100th anniversary of the Indianapolis 500 and was one of the fastest drivers in the weeks leading to the race. He won it in amazing fashion when race leader Hildebrand crashed in the final turn of the last lap heading to the checkered flag. Wheldon drove past Hildebrand's crippled car to win his second Indy 500.
Because of that victory, Wheldon was part of a promotion in which he would start last in Sunday's 34-car field, but if he won the race he would split $5 million with a fan.
And earlier Sunday, Wheldon had agreed to that full-time ride with Andretti for next season.
"We had just literally inked the deal this morning for him to replace Danica Patrick in the No. 7 GoDaddy car," Andretti said. "He was a very close friend. We had great plans to do a lot of fun things together. It's part of our sport. He knew the risks. We all know the risks when we get in the car. We are going to miss him."
The crash was triggered when Wade Cunningham's car hit James Hinchcliffe's rear wheel, which caused Cunningham to slow down. Rookie driver J.R. Hildebrand's car slammed into the right rear of Cunningham's car, launching it into the air. That triggered a massive, fiery crash that involved nine other drivers (Townsend Bell, Jay Howard, Tomas Scheckter, Charlie Kimball, Paul Tracy, E.J. Viso, Alex Lloyd, Pippa Mann and Buddy Rice).
"In this kind of racing there is not much room for error," Cunningham said after the crash. "I'm not thrilled about it. But it is what it is, and at this point it's kind of immaterial because there are some people hurt in there. I'm just keeping my fingers crossed for everyone in the accident."
Entering the race, drivers feared that with speeds at 225 miles per hour and with a track so smooth and so wide, that it was too easy for all the cars on the track. It wasn't selective enough to separate the good drivers from the bad drivers. It created potentially dangerous pack racing.
"It's so brainlessly easy flat, but what it did do is put us back in the pack, which is not brainlessly easy," Power said Friday. "That's very tough. The race around here is going to be really difficult because it's going to be such a pack race, and that's what manufactures ... really tight-knit racing, which is really quite intense.
"There is no real strategy. It's going to be three-wide, and I don't see the pack stringing out much at all. We'll have to play it the best we can to stay out of trouble. This oval racing, when you are flat-out 100 percent, it is kind of ridiculous."
After the crash, cars were brought onto pit road. The drivers remaining in the race climbed out and tried to discuss the series of events.
"It was just a chain reaction, and everybody slowed down, got bunched up again and there were more crashes that started behind it," 2008 Indy 500 winner and IndyCar champion Scott Dixon said. "It's unfortunate because everybody knew it was going to happen. You could see from Lap 2 people were driving nuts. It doesn't even matter the speeds -- you can't touch with these cars. I was in the middle of that one, and it was pure luck that I wasn't in it."
A few laps before Wheldon's crash, Alex Tagliani and Ryan Briscoe made contact on the racetrack, but both were able to continue without crashing.
"It was like driving through a war zone," Briscoe said. "We all predicted something like this would happen. It was inevitable. ... These open-wheel cars, there is no room for error."
But at 225 miles per hour on a 1.544-mile oval, 34 cars may have been too many.
"I don't think anybody can predict this," Penske Racing president Tim Cindric said. "Racing is what we do. The more cars we have, the healthier the series is. It's unfortunate this happened. Racing is inherently a dangerous sport. That's the thrill of why these guys do it, why we do it and why it's entertaining to watch -- the unpredictable nature of it. We've all seen days like this before -- we just hope they are minimized."
Added Franchitti, "You know I love hard racing, but that to me is not really what it's about. I said before we even tested here that this was not a suitable track for us, and we've seen it today. You can't get away from anybody. There's no way to differentiate yourself as a car or a driver. People get frustrated and go four-wide and you saw that happened."
Wheldon's death drew a reaction from drivers in all forms of motor sports, including NASCAR Sprint Cup driver Dale Earnhardt, Jr., whose father -- seven-time Cup champion Dale Earnhardt -- was killed in a crash in the last turn of the last lap of the 2001 Daytona 500.
"I had the pleasure of meeting Dan Wheldon at the National Guard Youth Challenge dinner about five years ago, and we crossed paths several times since then, mostly through our mutual partnership with the National Guard," Earnhardt said. "His success as a racer speaks for itself, but I will remember him as a true professional who was friendly, respectful and genuine. On behalf of everyone at JR Motorsports, I send condolences to Dan's family, team and friends in the racing community."
Tony Kanaan was another of Wheldon's closest friends. Because he was the leader of the race at the time it was stopped, he was on pole position during the five-lap tribute to Wheldon
"What a cruel coincidence," Kanaan said. "God does things in a strange way. We were there through Greg Moore, and today I was picked for that role. Another one of my best friends went.
"I just pray that he rests in peace, and I give my support to all of his family. He was one of my best friends and greatest teammates. As race car drivers we have to block this from our thoughts. Unfortunately, racing is dangerous. This has been happening for years, for ages, for decades. It's just hard to swallow, but we have to move on. None of the drivers that lost their lives want us to quit.
"We're not quitters; we're racers."
Wheldon's death is the seventh to happen in this form of racing since 1996. Scott Brayton was killed in practice for the 1996 Indianapolis 500 after he won the pole one week earlier. Jeff Krosnoff was killed in a CART race at Toronto in July 1996. Gonsolo Rodriguez was killed in a CART practice at Laguna-Seca in Monterey, Calif. in 1999, and Moore was killed in the CART race at Fontana, Calif., two months later. Tony Renna was killed in a tire test at Indianapolis Motor Speedway in 2003 and Paul Dana was killed in a warmup before the season-opening race at Homestead-Miami Speedway in 2006.
Wheldon became the fourth Indianapolis 500 winning driver to die the same season he won the world's biggest race.Gaston Chevrolet won the Indianapolis 500 in 1920 and was killed in a race at Beverly Hills, Calif. In 1929, Ray Keech won the race and was killed the next month at Altoona, Pa. In 1946, George Robson won the Indianapolis 500 and was killed later that year in a race at Atlanta.