Drivers crash during a wreck that involved 15 cars during the IndyCar Series’ auto race at Las Vegas Motor Speedway that claimed the life of driver Dan Wheldon. Will Power (12), of Australia, is airborne at left. Photo: Associated Press Oct. 16, 2011

Dan Wheldon was killed when his head hit a post in the fencing at Las Vegas Motor Speedway – contact that created a “non-survivable injury” to the two-time Indianapolis 500 winner.

The cause of death was revealed Thursday when IndyCar presented its findings of the Oct. 16 accident in the season finale. The crash collected 15 cars, including Wheldon, who came from behind the initial contact, launched over spinning cars and sailed approximately 325 feet into the catchfence.

Here’s the release from IndyCar:

Dan Wheldon, the 2005 IZOD IndyCar Series champion and two-time Indianapolis 500 winner, suffered a non-survivable head injury Oct. 16 in a 15-car crash in Turn 2 of Las Vegas Motor Speedway during the final race of the 2011 IZOD IndyCar Series season.

“There are multiple factors that are not uncommon to racing that came together in a way that claimed Dan’s life,” said Brian Barnhart, President of Operations, INDYCAR. “It is a tragedy. Our thoughts and support will always be with Dan’s family.”

The accident review revealed that Wheldon’s path on the lower portion of the racetrack was blocked by the multi-car crash he was approaching. The No. 77 car became airborne and ultimately impacted a vertical post of the track fencing. The pole intruded the cockpit, and the impact with the driver’s helmeted head produced non-survivable blunt force trauma.

The response to the scene by INDYCAR’s Holmatro Safety Team was rapid and decisive, according to the review.

INDYCAR analyzed data from the accident data recorders carried on board each race car involved in the crash, the on-board data acquisition system from teams, timing and scoring data, video, still photographs, physical evidence and eyewitness reports from participants. Third-party experts with Indianapolis-based Wolf Technical Services provided independent assurance that the investigation protocol, evidence examined and reviewed, and the conclusions reached are consistent and appropriate to standard scientific and engineering investigation methods.

Examination of video of the incident demonstrates normal “pack racing” that is common on high-banked ovals. However, there was almost unlimited movement on the track surface under race conditions not previously experienced that is attributed to track geometry beyond banking. Such freedom of movement outside of normal racing grooves not only increased the probability for car-to-car contact, but made it more difficult for drivers to predict the movement of other drivers. As a result, the opportunity for this incident was increased.

While this incident could have occurred at any track at any time, the dynamic of the current car and the overall track geometry at Las Vegas Motor Speedway under race conditions appears to have been one of the contributing factors in this incident.

The 34-car starting field was determined to be acceptable based on factors such as length and width of the racetrack and pit space capability. This incident and its consequences could have occurred with any size starting field at any track.

“INDYCAR’s commitment to safety was enhanced by Dan Wheldon’s testing throughout 2011 of the new car to be used by INDYCAR in 2012,” said Randy Bernard, CEO, INDYCAR. “The 2012 IZOD IndyCar Series season ushers in an era of a new race car and the opportunity for continued safety advancements. Dan Wheldon was instrumental in the testing and development of this new car and the safety innovations that it represents. We are thankful for his efforts and commitment to racing.”

The 2012 Dallara Automobili chassis enhances safety components such as side intrusion panels and wheel tethers. The cockpit is longer and wider than the decommissioned monocoque, which allows for additional padding underneath and behind the driver. Also, a “floating headrest” works in conjunction with the mandatory FHR (Frontal Head Restraint) attached to the helmet. Driver positioning allows for better sightlines.

In an earlier report by the AP, the IndyCar Series won’t return to Las Vegas Motor Speedway next season, and its future at the track depended in part on what it learns from the investigation into Dan Wheldon’s fatal accident.

Speedway Motorsports Inc. owner Bruton Smith was adamant he wanted IndyCar to honor the three-year lease deal it has with Las Vegas, but IndyCar CEO Randy Bernard had been reluctant to return to the speedway.

“We’re not guaranteeing we’ll be back,” Bernard said. “But we’ll test there, and we’ll see what we can learn.”

No matter the results, concerns remain about the emotional issues the series would face upon returning to Las Vegas.

The organization has spent considerable money on research into fencing. SMI owner Bruton Smith strongly stated that his fences are the strongest and safest in the business, and he makes no apologies for constructing them with the posts inside the wiring.

The race had a season-high 34 cars, but IndyCar CEO Randy Bernard said Thursday the field could have had as many as 37 drivers based on the size of both the track and the pit lane. The season finale was held on Vegas’ high-banked 1.5-mile oval with multiple racing grooves, which IndyCar president Brian Barnhart said created “nearly unlimited movement on the track surface under race conditions.”

That, not the construction of the fencing, played a larger role in Wheldon’s death.

Bernard had a three-year lease agreement with the track to stage the season finale at Las Vegas through 2013 but came to an agreement with SMI last week to buy out next year’s portion of the contract.

“I think Las Vegas is a great city, a resort destination and the fans and the sponsors – everyone loves the city,” Bernard said. “But I don’t want to go back there if the conditions aren’t right for our race cars.”

IndyCar plans on judging all high-banked ovals individually going forward and said the Wheldon accident could not be blamed on the banking. That leaves room for a deal to be worked out with Texas Motor Speedway, one of the most popular venues on the IndyCar schedule.

So questions remain about Las Vegas’ future on the IndyCar schedule, which very well may be released Friday.

Associated Press