Citing a pair of accidents that involved side cockpit intrusions, the IndyCar Series and chassis supplier Dallara have decided to make significant, paddock-wide updates to the spec DW12 Safety Cell.
RACER has learned the entire fleet of DW12 tubs used by IndyCar teams will be required to undergo a number of driver safety upgrades beginning in mid-January. Primary cars must have the modifications completed prior to the first race at St. Petersburg in March, and back-up cars will be expected to go through the process ahead of the Indy 500 in May.
Photos courtesy of Justin Wilson.
The move comes in response to two crashes, the first with Sebastien Bourdais at Sonoma in 2012 and the other in October with Justin Wilson at Fontana, where heavy blows caused their respective cockpit walls to crack, collapse or break.
The left side of Bourdais’ Dragon Racing DW12-Chevy struck Josef Newgarden’s gearbox in a coming together at the scary-fast Esses, pushing the cockpit wall inwards and delivering a heavy blow to the Frenchman’s ribs. Wilson was hit on the right side of the cockpit by the nose of Tristan Vautier’s car parallel with the steering wheel coming off of Turn 2, splitting the wall and pushing it inward. The crash fractured the Briton’s pelvis in two places, among other injuries.
With Wilson’s accident occurring at the season finale, the series has used downtime to identify the best methods to fortify the DW12 chassis ahead of the 2014 season.
The series and Dallara have contracted Indianapolis-based Aerodine Composites Group to carry out the modifications, which include the addition of approximately 20 pounds of cladding to the cockpit sides and reinforcing the cockpit ring (opening).
Speaking with IndyCar’s president of competition, Derrick Walker, the Scot says it was time for the series to act and look for ways to reduce cockpit damage where blunt force is applied in high speed crashes.
“This decision was a direct result of a second chassis demonstrating that if you hit the car at the right place, it was possible to go beyond the overall limits and ability to sustain high speed side impacts,” he told RACER. “The test that was done on the chassis when it was first being designed was FIA approved and administered through the FIA. The chassis wasn’t below par. The chassis in both crashes did their job. What we, and certainly from my own perspective, want to find out going forward is how we need to differ our thresholds from the (FIA) standards. When we look at what IndyCar racing is, it’s not necessarily going to follow that what happens in Formula 1.
“Just because Formula 1 cars can withstand certain loads doesn’t mean it’s good for all kinds of racing that it’s the reference standard, if you will. I think our levels require, for obvious reasons, much higher limits. So when we saw what happened with the last crash with Justin Wilson, again, the chassis did everything it was supposed to do. It took the load and took actually more load than the original FIA test. But clearly, Justin didn’t get out scot-free. He had some damage, so we looked at it and said, ‘Well, if that had been a higher impact, what would’ve been the result?’ And, of course, we had no way of knowing that at this point, so we’ve gone ahead with making the sides of the car stronger.”
The new side panels, which will add to the Zylon anti-intrusion panels that come built into the DW12, will be bonded to the inside and outside of the tub. The cockpit rim strengthening procedure will take place at the same time.
Teams are required to strip their tubs bare, barring a few brackets and other minor items, and all graphics, paint and filler will be removed, allowing Aerodine to work with bare carbon fiber surfaces. Once the upgrade process is complete, teams will need to apply new paint or graphics to the tub and reassemble their cars.
Each tub is expected to spend three days at Aerodine, and with the disassembly, stripping, shipping (or drop off, depending on where the team is located), return, livery addition and reassembly, one leading team estimates 10 days per tub will be consumed.
From a speed and performance standpoint, adding the 20 pounds of reinforcing material to the DW12 is far from optimal, but Walker hopes it will be accepted as a necessary round of safety improvements.
“We got with Dallara and they did some modeling and came up with some very good changes, and they’ve been not only cooperative, but they’ve been very helpful in that analysis and very proactive,” said Walker (LEFT). “We’re trying to be more proactive, and with safety, you can’t put a bandage on problems. There’s always an ongoing evolution of ideas and technology and needs. We’re doing more Zylon pads for the walls on the monocoque, and we’re also looking at adding some more protection between the seat bucket and the side of the chassis.
“Weight is the last thing we really want but, in reality, we were getting ready to address the driver weight situation anyway because people have pointed out to us, mainly drivers with higher weight levels, that it isn’t totally fair that a heavier driver ends up being penalized with the current system. So we were getting ready to try and address some of that. So adding more weight to the car is unfortunate, but we have to react to what’s safest in terms of pushing the loads up higher than where we currently are.”
Once the Aerodine updates are complete, the DW12s will return to service immediately, and will not require additional FIA crash test certification. The basic monocoque structure that underwent and passed FIA crash certification will not be compromised in the upgrade process, but an old-school, less formal test could be in the offering by Walker’s tech team.
“No, it’s not a requirement because the car already meets the FIA standards,” Walker confirmed. “What we’re doing internally is where I would personally like to see us get back to the old-fashioned testing, which is you take a chassis and you get a big concrete block and you whack it. The current testing by the FIA is a push test by a computer-controlled hydraulic arm it’s a calculation, not necessarily a physical test. Because the software programs have all the material content in their database, you apply a certain force inside of the car, you can measure the deflection and from that the computers are smart enough to figure out what the limits are.
“I think that’s perfectly fine but I think we need because we’re going to stay with this car for some time yet
we need to know exactly where we are with the cockpit sides. And being an older member of the team, I favor going back to hitting it with a big concrete block as being the closest thing that I can see to being in the real world. I’m sure the FIA could give us that information but I think we owe it to ourselves to take a look. It’s one thing to use machines in a laboratory to push on the side of the car, but in the real world, it’s big, heavy things running into them and that’s how we used to have a look and see for ourselves how it stands up. We have to raise the bar.”NEW HEADREST MATERIALS
Drivers have complained about the material used in the DW12’s cockpit head surround piece for quite some time, asking for something less dense to help absorb smaller blows. At present, one type of solid foam is used and offers minimal energy absorption in the most common accidents. The exact material (or materials) has yet to be defined, but changes are on the way.
“What put us onto this was Will Power,” added Walker. “He said to me that at Mid-Ohio, when he went off and ran across the grass and the car was bumping around and his head was slapping back and forth against the headrest, that it almost made him dizzy because there was no forgiving in that headrest. It just was hard as a rock. And, of course, on a road course they take the foam off that normally sits between the helmet and that surround (teams will add softer foam between a driver’s helmet and the surround on ovals to prevent movement from buffeting), and it rattled his head. That really was a red flag for me to ask what’s going on there.”
In a conversation with new Team Penske driver Juan Pablo Montoya earlier this week, the ex-Formula 1 pilot expressed his desire to see IndyCar move to a head surround system that follows what F1 practices.
Ambient temperature has a direct influence on the stiffness of the foam used on the helmet surround piece, with cold hardening the material and heat making it too soft. As a result, the FIA calls for teams to install different helmet surrounds that contain foams of varying densities to conform to specific ambient temperature ranges.
“It was one of the things I really wanted to see when I went down to Austin for the Grand Prix, to look at what Formula 1 does,” Walker continued. “As Montoya rightly said, they have a very similar type device as ours but they do adjust it for various climates and they don’t have the oval situation where you don’t want something that collapses a lot. You want something very firm because the head is almost snug in between those things so your head doesn’t launch out the side of the car quite like it does on a road course.
“So, that started us looking at it and saying, OK, we obviously needed to have another head surround. Both the head surround and the foam that goes inside that surround. So our boys have been up on the testbed already. We started doing some tests to determine what needs to be done and what’s the best for us to get out there. When we get to St. Pete we will have a different head surround; it will look very similar but would react quite differently. And that’s because we do need some changes in our head surround for the conditions that we incur.”
High kickback forces through the DW12 steering wheel have led to multiple thumb and wrist injuries. One of the ideas Walker floated was the addition of a damping system to the steering rack to lessen shock, which has now become an R&D item.
“We reached out to the teams and asked who wanted steering dampers, and said it’ll cost roughly about x amount of dollars, because volume pricing depends on the number of people that buy it,” he said. “And it is still very much a development piece in the sense that I’m sure we can make a damper, but one thing we don’t want is to add any more steering drag, because at high-speed tracks some of our current drivers have a difficulty in actually turning the wheel because the downforce is so high.
“So, ideally, we would’ve preferred to have power steering. We looked at power steering and there were some real challenges to doing that, not only the system to drive it but actually to put it in there and get one that would fit. And the cost was quite high. So there was an easy solution with the steering damper with this current configuration that we’ve got for the car. So we opted to talk to Dallara about how to produce a steering damper.”
The next step will be for the series to see how it performs during on-track testing.
“Dallara has developed a steering damper with another partner and they’ve installed it into the steering on a [DW12],” Walker continued. “And IndyCar because we don’t see us getting there any other way we’ve put the money up to help build the first prototype to prove it works. And I think it’s one of those development pieces that will come in over time if it works. It wouldn’t come in as being mandatory right away. We would let the teams try it and, obviously, the more they try it and experiment with it, we get a chance to see it in action and ultimately, we would like to think that the teams would say we’ve got to have it and put it on through their own free will.
“But, obviously, right now they’re a bit guarded about it because it’s not a given that it’s going to do everything we expect. We can sit around and second-guess ourselves on that but IndyCar has initiated it with Dallara, we went ahead and let’s get it out there and see how it does. So that’s something worth following up on because it’s an issue the drivers have explained and the teams have talked about for a while about the whiplash that comes back through the steering. We are hoping this is going to be one of the solutions.”REVISED STEERING ARMS, FRONT UPRIGHT STEERING BLOCKS
Drivers also suffered wrist and thumb injuries with wheel-to-wheel contact, and while hitting barriers wheel-first. Steel steering arms are the norm in IndyCar, but aluminum versions were produced by Dallara and tried by a few teams starting at Mid-Ohio last year.
The goal behind using aluminum rather than steel is to soften the connection point between the wheels and the steering rack, allowing the aluminum arms to bend when a heavy blow is received, which would reduce the energy fed into the drivers hands through the steering wheel. Lightening the steering arm mounting brackets has also been proposed.
“I would like to think it would become mandatory ultimately when we finish experimenting with this,” said Walker. “Dallara was initially concerned about lightening them too much for creating some other issues in stiffness. But we are looking at that so maybe there’s a stage two that comes out that is the next step. And then, ultimately, I would say that once we’ve got something that is where we need it to be, I think it should be across all configurations, whether it’s oval or road courses, it should be mandatory. One of the things that happens when we look at these things is that we can come across and say, yes, let’s do it, we’re very aware of the knock-on effect, so to speak, to the teams in terms of costs.
“When it comes to driver safety or improving the breed, it shouldn’t be about money. But at the end of the day, rather than mandate it, we prefer the teams to make that decision. And we get with Dallara and we try to negotiate to get the best price we can so that we minimize the impact of the teams. The teams are not rolling around in money and, of course, on the horizon, we’ve got a mammoth aero kit coming with a different floor that will also cost money.”
NEW FLOOR FOR INDY?
Aero kits are on the way for 2015, but IndyCar has a revised floor being readied for testing that could be used as early as the Indy 500, although that timetable appears to have recently moved.
The DW12’s massive floor not only generates massive amounts of downforce, but also produces lift when the car gets sideways or turned backward at a high rate of speed. Reducing the floor’s plan area would help with problem, but the timing of the floor’s introduction could be pushed back until 2015.
“We thought with everything else we’re doing, this was a golden opportunity to actually reduce the surface area on the bottom of the car because we felt that the size of the current underbody is a bit bigger than the old floor,” Walker explained. “And, of course, as we all know, in very unique situations it creates lift. The larger the bottom, the more lift you get.
So we took it upon ourselves to say, OK, aero kits, perfect time to reduce the floor. Let’s go about it and let’s look at what’s the impact and how much floor reduction do we need. So we worked with Dallara, we worked with Pratt & Miller at Chevrolet, we’ve worked with Wirth Engineering with Honda. And we’ve used their expertise to help us analyze the right way to do it.”
The series will test a few different floors early next year and then decide when to bring them online.
“We’ve got a direction and Dallara is designing and making sample floors,” he added. “Now, the floors may be a modification of the existing floor, we certainly hope it is so we minimize the cost to the teams, and we’re going to continue to test them. So I wouldn’t say that the floor is guaranteed to be a 2014 introduction. There’s no way in the world we want to jeopardize the Indy 500 or any of our races at the moment by going off half-cocked with a completely different underbody. And the underbody basically reduces the downforce because you’re making it smaller.”
EVALUATING LOWER-DOWNFORCE SPEC FOR ROAD AND STREET COURSES
IndyCar asked some of its teams to try running at a lower downforce settings during recent tests at Sebring and Sonoma, calling for a reduced rear wing angle that shed approximately 120 pounds of downforce in road course trim.
“Well, the mindset was when (IndyCar VP of technology) Will Phillips (pictured at right, with Walker and Mitch Davis) with Walker and and the boys looked at the range of downforce that people used this year, the reduction in that rear downforce did not seem to be much of an issue,” Walker noted. “Why do we want to reduce the downforce? Well, there’s always some drivers that say we’ve got too much aero and not enough engine power. So Will came up with the belief in our internal meetings that we should look at a small reduction, and that from his numbers looking at what teams have done, it’s possible and it wouldn’t really affect things too much.”
Feedback from the drivers who tried the rear downforce reduction felt it would hinder the show.
“We tried it and the drivers said they thought it would hurt the quality of racing,” he said. “And so we’ve reversed that decision. Ryan Hunter-Reay was very clear in his description about how it made things harder in zones where you’d try to make passes, and that’s not what we intended so we tried it, got feedback, and did away with it.”
The laundry list of safety improvements and other off-season changes represent the greatest amount of influence Walker has exerted in the seven months since he joined the IndyCar Series. More updates are also being defined, including a thorough evaluation of the rear wheel guards which are expected to be altered and improved for 2014. For a series that has often been slow to react to problems, the plans currently being enacted are a refreshing change in direction for the organization.