Slipstream Network

Concerns Arise Over Loose Belts in Detroit

CORRECTION: The Slipstream Network published this article regarding the undoing of two Verizon IndyCar Series drivers’ seatbelts during the Chevrolet Detroit Belle Isle Grand Prix. The image used as a header for the article was selected from a gallery available for media use from the series. The image featured a belt/harness system manufactured by Willans.

The image used was not representative of the story of the article other than simply being of a belt/harness system. The company has clarified that neither driver in the story was using a Willans supplied belt system. Willans produces top quality products and continues to improve driver safety in many levels of motorsport.

The Slipstream Network apologizes for the inclusion of the Willans name in the header image of the article and has updated the post with a more relevant image

A pair of potentially alarming circumstances occurred during this past weekend’s Chevrolet Dual in Detroit. Verizon IndyCar Series drivers, Mikhail Aleshin and Graham Rahal, reported that some of their belts had become “undone” during on-track sessions. Rahal shared on social media shortly after Friday’s qualifying session that his belts had come undone twice, referencing an over-the-shoulder belt. Aleshin shared a similar sentiment on Twitter after race two. Both drivers confirmed to Slipstream Network on Sunday that their belts had loosened while on track.

Whether the track surface caused or merely exacerbated a possible design flaw with the belts, it’s bumpy characteristic was widely discussed throughout the weekend. The Raceway at Belle Isle features a concrete driving surface similar to such tracks as Sebring International Raceway and the now defunct circuit in Edmonton, Alberta. Concrete suffers more significantly from uneven settling due to it’s construction in large squares. Anyone who’s driven on a concrete road knows how bumpy the material can be, something much more problematic at 175 mph.

Adding to the issue, the manufacturer-specific aero kits introduced last season have added an appreciable amount of downforce. With more downforce, stiffer spring rates are used. The combination of which increases the magnitude of the vertical forces on the car and driver.

Though tightly regulated by the series rulebook, seat belt suppliers are open and a variety of options exist. The rules also require a quick-release mechanism to allow for rapid driver egress that is all too often needed. The design of the quick-release mechanism includes two bars for the belt to weave under and over – similar to a Double-D style belt used with common apparel. There is also a spring that applies pressure to ensure adequate friction, thus locking the belt in place.

“The bumpiness is what highlights it, but I think it’s a manufacturing error,” Rahal said when asked if it was the Bell Isle track, itself. The quick release mechanism has not been known to cause issues in the past, but Rahal recalled one other time that his belts had malfunctioned at a previous race at the Edmonton circuit. The Canadian track also suffered from the concrete turbulence seen at Belle Isle.

“I wasn’t sure if I was going to fly out of my cockpit,” Aleshin said after race two. The Russian driver has had belts come loose in the past, with his previous sports car experience in LMP2 machinery at Spa Francorchamps. Although still an issue at the Belgian track, it’s smooth character made it less of an issue. The situation could raise serious implications for the track and/or the seat belt manufacturer. “You can fly out of your cockpit on the backstretch because your car has downforce and you don’t have downforce,” Aleshin finished.

Rahal’s comments allude to a deeper dive at the root cause of the issue. “If you’re not strapped in securely and something happens and you crash,” Rahal warned, “It’s a dangerous game.”

Zach Wenzel contributed to this piece.

Photo: Chris Jones


Dusty Michael

As a mechanical engineer, Dusty’s passion is for sports cars and endurance racing. In his opinion, there’s nothing better than a race car closely based on a model that you can go out and buy from the manufacturer showroom. He’s very particular about his writing utensils and appreciates a great, cruelty free pomade.