Current NASCAR Cup champion Jimmie Johnson has stirred controversy and sparked anger among IndyCar fans by calling on the rival IZOD IndyCar Series to drop ovals from future seasons, after the devastating 15-car crash at Las Vegas Motor Speedway that resulted in the death of Indianapolis 500 champion Dan Wheldon on Sunday.

"Those cars are going so fast and get airborne so frequently on ovals that I wouldn't run them on ovals - there is just no need to," said Johnson, speaking during a break in NASCAR testing on Monday at Charlotte Motor Speedway. He was still sore from his own high-speed accident at Charlotte on Saturday night that probably put an end to his hopes of a sixth consecutive title - but at least he was entirely uninjured after smashing into the wall.

"Those cars are fantastic for street circuits and road courses," he explained. "The ovals at those speeds, you can't control the vehicle when it's off the ground. There's very little crumple zone around the driver, and obviously it's an open cockpit and then you add open wheels. You're just creating situations to get the car off the ground at a high rate of speed.

"I hate, hate, hate that this tragedy took place," he continued. "But hopefully they can learn something from it and make those cars safer on ovals. I don't know how you do it. Myself, I have a lot of friends that race in that series. I'd rather see them on street circuits and road courses--and no more ovals.

"It's been my dream to race the Indy 500," Johnson revealed. "But wrecks like that ... There's the racer in me that wants to, but I know how dangerous those cars are, and yesterday was proof of how dangerous those cars are on ovals," he said. "The risk factor is multiplied by ten," he added.

IndyCar fans saw Johnson's comments as an attack on IndyCar in general, but Johnson was quick to respond on Twitter to make it plain that this was absolutely not the case.

"I hate some of you don't understand my opinion of IndyCars not running on ovals," he wrote later. "It's only because I care. I'm a huge fan of open wheel racing and all things racing ... I don't want to see my friends hurt or another tragedy.

"I know Dan ... or knew Dan. I have a lot of friends that race in that series. We just stared at the TV for a long time with long faces. It was just really sad," he said. "Knowing Dan and his wife and his two kids, and I'm sitting there with my daughter running around in the backyard - I was tore up."

NASCAR's next race is at Talladega Superspeedway, where the use of restrictor plates to limit air intake into the engines in the series was overhauled to lower speeds to under 200mph following the death of Dale Earnhardt Sr. in 2001 after a high-speed accident.

"Why we run restrictor plates is so the cars stay on the ground," said Johnson "It doesn't matter the kind of race car. If it's off the ground, you cannot control it in an accident.

"Roof flaps help, cowl flaps, getting the wing off the back of the car helped [in NASCAR]," Johnson said. "There is a threshold for all the cars where they're airborne. And as we go to Talladega with a larger restrictor plate, we get closer to that threshold - that gets us closer to that lift-off point."

The open-wheel nature of IndyCar also contributed to the Vegas accident, from what Johnson saw: "In that crash, what got the cars off the ground was wheel-to-wheel contact ... The open-wheel vehicles, whenever they touch wheels, it climbs them and just catapults them and throws them up.

"It was cars climbing other vehicle's wheels. Having so much speed, they came in and just jumped off the back of another car. Some of that can be the structure of the vehicles and the way they're shaped, but I think the majority of it was tyre contact, jumping off each other."

The new 2012 IndyCar Safety Cell Dallara chassis - that Dan Wheldon himself had been leading testing on in recent months and which will now be dedicated in Wheldon's name - has new features to stop cars getting airborne so easily, and also incorporates controversial "bumpers" into its aerodynamic body work protecting the exposed wheels that have been unpopular with fans on aesthetic grounds before Vegas.

The catchfence was another problem highlighted by the tragedy, as Johnson pointed out: "That fence is so nasty... It shreds cars apart," he tweeted to Paul Tracy on the social messaging network.

While massive improvements have been made through the introduction of the impact-absorbing softer SAFER barrier system, the catchfence remains the single biggest threat to the integrity of a car involved in an airborne accident. After Sunday discussions have already been starting about how this could be improved in future.

But as Johnson's fellow NASCAR driver Jeff Burton pointed out, "You'll never reach safety ... It's not a goal [that you arrive at,] it's an effort," he added. "We always have to be working harder to make it better.

"The faster you go, the bigger opportunity for stuff," Burton continued. "The kind of pack racing they have there and what we do at Daytona and Talladega, it creates situations where you see spectacular wrecks. Anytime you have spectacular wrecks, you have the opportunity for bad things to happen.

"There's no question that our sport is the safest it's ever been," Burton added. "There is also no question that there are still things out there that have to be fixed ... We have to look and pay attention. I'll give the race tracks credit - the race tracks have invested an exorbitant amount of money on safety, but we're not there yet."

Elsewhere in the NASCAR paddock, Kasey Kahne was even closer to the tragedy than most of his stock car colleagues. He'd been seriously considering taking up IndyCar's $5m prize challenge to race at Las Vegas on Sunday, until his future team boss Rick Hendrick vetoed the plans.

"I was absolutely thinking about doing it," Kahne said. "Rick told me he didn't want me to do it, so then it was pretty much over at that point in time as far as doing the race.

"You can never think about if something like that would have happened or wouldn't have happened, you have no control over it," he said, refusing to play the 'what if?' game. "So I don't even think about that. Driving an IndyCar is something I've always wanted to do and definitely thought about doing for that race. It just didn't work out."

In NASCAR, Earnhardt Sr. was the last driver to die as the result of a racing accident. His son, Dale Earnhardt Jr., knew Dan Wheldon personally through shared appearances for their mutual sponsor, the US National Guard.

"He was a really great guy, a really nice person and very friendly ... He was just a real pleasure to be around. It's a tough deal," said Earnhardt. "I can't imagine how everybody, his family and everybody in that series is doing."

But Earnhardt, Johnson, Burton and Kahne did what true motor racing drivers always do at moments of extremis: minutes after sharing their thoughts with the press, they were back in their cars and heading out on track for more test laps.

Just like Dan Wheldon would have done.