Sebastien Bourdais, who broke his hip and pelvis in a nasty crash as he spun into the wall while going 232 mph in Indianapolis 500 qualifying a year ago, can look at his 2018 Indianapolis 500 ride and speak with some confidence.
"That crush structure [in this car] would have probably saved my hip and my pelvis," Bourdais said.
The new IndyCar design and aero kit for 2018 addressed the issue of the ability of the side of the car to absorb the forces of a crash before they get to the driver.
The changes in the design were already well underway before the Bourdais crash -- IndyCar engineers and Dallara had been working on it since mid-2016. The proof of the effectiveness of the design could be told over the next couple of weeks, as practice for the Indianapolis 500 (May 27, Noon ET, ABC) opened Tuesday at Indianapolis Motor Speedway.
The sidepods of the 2018 IndyCar include 8 to 10 inches of crushable structure on each of the side of the car to protect the 1-inch tub where the driver sits. A Takuma Sato crash in testing at Texas has shown the changes are working as expected, but IndyCar has changed the design slightly to allow it to crush more progressively.
The design of the sidepods, which have about an extra 11 pounds of weight, was still being finalized at the point of Bourdais' crash a year ago in preparation for testing last July.
"Historically, [the sidepod] has just been bodywork, a light composite construction," said IndyCar director of aerodynamic development Tino Belli. "We changed it into a pretty strong box structure, so the weight has gone up significantly, and it's been designed to take a side impact. ... When you try to absorb all the energy in the thickness of the tub, that's not the best way to absorb energy.
"The best way to absorb energy is to crush over a nice, long distance."
The cars that fans will see in this year's Indianapolis 500 have more of a longneck shape and have fewer pieces, another safety element when it comes to debris.
How the changes to the sidepods also changes the point of contact between the car and the wall in a spin remains to be seen, whether the car hits the wall rear-first in a spin rather than more headfirst.
The redistribution of weight also could impact how the car reacts when it does get airborne, such as when Scott Dixon's car soared through the air during the 2017 Indianapolis 500. It landed upside down on the IMS wall, and Dixon walked away from the accident. The wreck told IndyCar something it already knew -- its rear wheel guards, which no one liked from an aesthetic standpoint, had no real use when trying to stop any contact with the rear wheels.
"We looked at all of the incidents of wheel-guard contact since 2012, and in no case was there any evidence it significantly helped reduce the flying of the car in a wheel-to-wheel or nose-to-wheel situation," Belli said. "It gave us that extra confidence to keep moving in that direction.
"Obviously, a wheel guard flying through the air -- that was an 18-pound piece -- and if that flies through the air and hits another driver, that is very bad."
The next step in IndyCar safety likely is a windscreen to prevent a driver from being hit by debris. Dixon tested a prototype at Phoenix, and Josef Newgarden tested it at Indianapolis a couple of weeks ago.
The next test would likely occur on a road course. It would be implemented in 2019 at the earliest.
"Even though we have a lot of smart people working on it, there's things we are not completely aware of, things that could happen," IndyCar CEO Jay Frye said. "That's why you go through the process to test it."
Newgarden's team had to work in removing the glare from the body of the car onto the windscreen during his test, which IndyCar did in a late-afternoon session April 30. Helmet manufacturers likely need to be involved to make sure they have the correct visors to go with the windscreen. (A clear one? A tinted one a driver might use when the sun is going down?) The other questions would be whether IndyCar can stage a test in wet conditions and how well the drivers could see in a light rain.
"I never felt like I had to look over it -- it would be hard to because it was so high," Newgarden said. "If you look over it, you're looking at the sky. You're looking straight through it. That wasn't difficult at all."
IndyCar added a small duct to the front bodywork of the car to help with air flow on the driver (for both cooling and the way the air flows over the driver's helmet). The windscreen also attracted bugs, although it had tear-offs drivers often would use for visors or on stock car windshields.
"It picks up bugs pretty easily," Newgarden said. "We were talking about what the dirt-track guys do to create a flip-up to push everything over a visor or a windscreen. I think we can make that better, because it was accumulating bugs pretty fast."
James Hinchcliffe was hit by a front-wing upper flap and suffered a concussion during a race in 2014. He thinks the small issues can be addressed.
"There's obviously still little challenges that arise from adding something as majorly different to the cars as that," Hinchcliffe said, "but if we solve the big problem, I think we'll have no problems getting around the little issues that come from that, and I look forward to getting it on a race car."