Dallara’s replacement for the aging 2002-era Indy Lights chassis is expected to turn its first laps this summer, and when it does, project leader Tony Cotman says it will feature the highest level of driver safety the IndyCar feeder series has ever offered.
“With the Dallara IL-15, it’s critical we take everything the IndyCar Series has learned in recent years and also in recent months with Dario [Franchitti’s] crash at Houston and Justin [Wilson’s] crash at Fontana and incorporate all of the updates into the new Lights car,” Cotman told RACER.
“We’ve had access to all of the data, all of the anti-intrusion improvements, and have also taken a page from the current IndyCar design to give Lights drivers as much room inside the car as possible,” he added. “We’ve spent a lot of time on the IL-15’s monocoque; it’s basically identical, from the pedal bulkhead back, to the IndyCar chassis. You could take the seat out of an Indy car and drop it right into the Lights car and it would fit perfectly.”
After Wilson’s crash at Fontana – one where the nose of Tristan Vautier’s car punched the right cockpit wall of the Briton’s car inward by a few inches – the IndyCar Series mandated additional sheets of bullet-proof Zylon panels to be bonded in place on both sides of the chassis. The IL-15 will feature the same robust Zylon treatment once Dallara begins production.
“Side penetration is a big area we’re concentrating on, and these panels are actually part of the original construction instead of add-on panels,” Cotman continued. “And they’ll also run from the pedal bulkhead all the way back to the back of the monocoque, so the full length of where the driver sits is covered. That’s an upgrade from the current Indy Lights car.”
Renowned Indy car surgeon Terry Trammel and IndyCar Safety Team leader Jeff Horton have played a central role in the IL-15’s cockpit layout, according to Cotman.
“A lot of what we’ve done inside the car has been with input and guidance from Terry and Jeff, and without their feedback, we’d be standing still on taking this car’s safety forward,” he said. “We’ve added two inches of clearance beneath the driver’s seat with impact absorbing foam, added three inches behind the driver’s seat and foam there to help with rearward impact, we have the same leg cushioning – and all the other items carried over – from IndyCar to keep our drivers from being too banged up in a crash. It’s just an overall modernization process with the new car, and Dallara has been doing some extraordinary work so far.”
Bringing IndyCar safety technology to the smaller, lighter Indy Lights car makes sense, and with two season of learning from Dallara’s DW12 Indy car chassis to draw from, the Italian constructor is essentially creating a new Indy car tub built to a slightly reduced scale and with different styling features. Some areas of the IL-15’s design have also been altered to accommodate new safety findings.
“We’ve done a lot of other little things that people might not see, but we want to improve,” Cotman explained. “We’ve now moved the [brake] master cylinders, for example. In IndyCar, they mount primarily on hard spots on the floor in front of the bulkhead. Dr. Trammel didn’t like what he saw in Dario’s crash; they punched through the bottom of the floor and pushed the pedals onto the driver, so we’ve taken his recommendation and mounted them directly to the bulkhead itself. That was an extreme situation with Dario – it may never happen again – but we don’t to take any risks so we’ve incorporated those changes in the new Lights tub.
“We’ve moved the radiators up beside the driver to help absorb energy in an impact. The floor and underwing is quite a structural piece – a lot stronger than usual – to help absorb a side impact. The same with the sidepods and inlet ducting for the radiators.
“We’ve raised the cockpit sides on the car to better protect the drivers, and gone to the same IndyCar-style helmet surround. We’ve lengthened the nose of the car to provide more energy absorption in a frontal impact. We’ve taken some of the concepts behind anti-wheel intrusion and brought them into the new car to make it harder for cars to run over each other from behind or the side. The chassis is also significantly lighter but stronger, so there’s less mass to be concerned about in an accident.”
Cotman says the new Lights car has also been designed to fit the same range of short-to-tall drivers found in the IndyCar Series, and hopes the strides made in safety will add to the growing interest surrounding the IL-15.
“Yeah, we’ve modeled everything to fit Justin [Wilson] at 6-foot-3, [Takuma] Sato at 5-feet-nothing, and because the cockpit dimensions are the same as an Indy car, although the tub outwardly is smaller, all of the padding and the other pieces are the same. Our goal was to have an IndyCar driver sit in both cars, close their eyes, and not be able to tell the difference. We think the similarity is important from a safety perspective, and also from an experience standpoint.
“And yeah, the Lights car has 500 horsepower and the IndyCar is over 700, the downforce is different and all that, but when a kid graduates from Lights to IndyCar, he or she won’t be stepping into something that feels different. It’s important for us to tell prospective buyers, the moms and dads of our drivers, the sponsors and anyone else that our new Lights car is really fast, really modern, but most of all, it’s been designed from Day 1 to be as safe as it can possibly be.”