IndyCar strengthens rear-wheel retaining nuts for Iowa Speedway after flying tire at Indy 500
For its first oval race since a tire flew over the grandstands during the Indy 500, the NTT IndyCar Series will have new rear-wheel bearing retaining nuts that are 60 percent stronger this weekend at Iowa Speedway.
IndyCar and Dallara (the series' exclusive supplier of its DW12 chassis since 2012) announced the mandated safety enhancement Wednesday morning after completing a review of the May 28 collision between Kyle Kirkwood and Felix Rosenqvist on Lap 183 of the Indy 500. Kirkwood's No. 27 Dallara-Honda was traveling at about 161 mph when its wheels interlocked with Rosenqvist's No. 6 Dallara-Chevrolet (which was traveling backward at about 90 mph), and the impact resulted in the loss of Kirkwood's left-rear wheel assembly.
INDYCAR AT IOWA: Details, schedules for watching this weekend on NBC, Peacock
“Dallara continues to be a tremendous partner of the NTT IndyCar Series,” IndyCar president Jay Frye said in a release. “Their thorough review process of the incident between the No. 6 and the No. 27 at Indianapolis Motor Speedway began immediately and included an extensive re-creation at their headquarters in Italy.
“IndyCar takes safety very seriously. This update is an important step in making sure an incident like this does not happen again.”
IndyCar reiterated that the wheel tether system did not fail in the incident. The IndyCar tethers can withstand a force of more than 22,000 pounds, and the rear wheel tethers were strengthened before the 2023 season.
The series began mandating wheel suspension tethers using high-performance Zylon material after a flying tire killed three fans at Charlotte Motor Speedway during a May 1, 1999 race. Three fans also were struck and killed by a tire at Michigan International Speedway during a July 26, 1998 race. During the 1987 Indy 500, a man was killed when a loose tire hit by a car was launched into the Turn 3 grandstands (the most recent fan fatality at IMS).
No one seriously was hurt in the Indy 500 incident (including Kirkwood, whose car went upside down and slid for several hundred feet), though an Indianapolis woman’s Chevy Cruze was struck by the tire. The Indy Star reported a fan was seen and released from the care center after sustaining minor injuries from flying debris in the crash.
IndyCar and Indianapolis Motor Speedway owner Roger Penske met with dePonti and Dallara founder and owner Gian Paolo Dallara on the day after the Indy 500 to discuss the loose wheel that Penske said "was probably the scariest thing. We’ve got to fix that so that doesn’t happen again.”
“It is Dallara's mission, along with IndyCar and all of the racing series we work with, to maintain and continuously improve safety based upon the highest standards,” Dallara CEO Stefano dePonti said in a release Wednesday. “After completing a detailed analysis of the accident during this year's Indy 500, together with IndyCar we have reached the conclusion that the outcome was the consequence of an unusual and never experienced set of circumstances.
"Nevertheless, we have developed and produced new components that will increase the strength of the corner in case the unlikely sequence of events repeats itself.”
The IndyCar Series will hold its only doubleheader race weekend of the season at Iowa with Saturday's race at 3 p.m. ET and Sunday at 2 p.m. ET. Coverage will be on NBC and Peacock.
