An incredibly heavy emphasis on aerodynamics is present at most top level series and INDYCAR is no exception. I have been sitting on this post for a while, but with Carl Edwards’ recent remarks to speed.com about the aero dependence of cup cars, now seems like a good time as ever to figure out the solution to a problem that looms with the new indycar’s release in 2012. I went into this year’s 500 with the assumption that the air is even cleaner off the rear of the cars this year than in the past. As I was wondering through Gasoline Alley in the weeks leading up to race day, I could not help but notice the rear of the cars look cleaner than they ever have. The gear boxes are petite, and the bodies sweep low and close, refining the airflow over the back of the car. I would have bet five dollars the cars would be even less aero dependant than last year. The rears just look sleeker and sexier this year.
Just the opposite seems to have happened. After a year of less dirty air and the return of great oval racing, now the cars can’t run side by side Texas for more than a few laps. I don’t exactly recall, but I believe it was last year that INDYCAR moved the hazard light from between the rear wing uprights, to the attenuator to pull more drag off of the car and clear the airflow leaving the rear of the car. They also removed the two vertical wicker bills from the endplates of the rear wings to, again, clean the airflow. I found the wicker bill delete very humorous; I very clearly remember watching a segment on WRTV 6 here in Indy about the new chassis’s that were coming out in 2003. One of the focus points on the car was the addition of these very wicker bills to increase passing, yet were removed seven years later to increase passing. These improvements, in addition to the development of wheel backing plates, side pod extensions and wheel ramps that were all added to the indycar spec in 2009, reignited the oval racing insanity that helped put the IRL on the map. That aero balance seems to have been greatly diminished this year. I am sure it is an effect of teams perfecting these new tools and pushing them to their technical limit, increasing and refining down force areas can and almost always does increase dirty air behind the car.
As different series look to the future, the effects of dirty air to the following car has come into the forefront in regards to new car design. In 2009, Formula One completely redesigned the aero package of the cars in an attempt to reduce the effect of dirty air. They even went as far as seriously looking into the split wing design you see at the top of the page. Even with the improvements in cleaning up the air, passing was still virtually impossible. The series has had to result in movable wings for the trailing car only, and tires that tear themselves apart after only a handful of laps. In his 3400 pound stock car, Edwards can feel the wash from the leading car disturbing his vehicles dynamics and making it difficult to follow closely. This is a clear indication that aerodynamics rule the roost in racing. He is lobbying for a decrease in down force when the 2013 rules are released. Ferrari boss Stefano Domenicali has been on the record this year saying that F1’s infatuation with aerodynamics is reaching critical mass and must not continue to be the focus of F1, as it is not the focus of the automobile industry, as a whole. In an era where the only engine development seen in F1 is to increase down force, this is a totally believable statement. Last year at the MotoGP Indianapolis Grand Prix, the majority of the work Ducati was doing in the practice sessions was experimenting with new aero pieces to give their bike more front end grip.
With the new car/engine/rules package for next year, this has to be a worry for Tony Cotman. What is the motivation for the aerokit manufacturers to produce a kit that will not create an undrivable wake, making it difficult for following cars to get close and pass? Huge amounts of down force can be extracted from the undertray of the car, while leaving relatively clean air behind. Cotman has said that the majority of available down force will be created by the floor. Because of this, the outboard wings may play a much smaller role in the stability of the new car. I have always envisioned an Indy only kit with very small, if any true wings on the car. The rough spot comes with the engine cover. I noticed on the road version, there were several small winglets and flip-ups on this portion of the kit. F1 banned these very items in an attempt to clean the air moving over the actual bodywork of the car. Here, as with the floor, huge aero gains can be realized but at the expense of drag and dirty air coming off the rear onto the following car.
Cup cars are wind tunnel tuned to find every aero gain they can, yet are scrutinized by “the claw”, a template designed to standardize body shells, used in tech inspection at the track. How standard can they be if teams have multi-million dollar aero departments? INDYCAR has a chance to stop these out of control and detrimental to racing practices before they start. The 2012 chassis rules are the perfect chance to show the world what a progressively designed aero package can do for big time open wheel racing. Homogenizing body pieces at the start of the season is thought to be in the new rules, making mid season aero kit updates disappear all together. Give as much down force needed from the floor, yet make the kit makers prove the hardware they provide will still allow for clean air flow to the following cars. As an added bonus, less turbulence equals less drag equals more fuel efficacy, a goal in the INDYCAR series. Indycar racing can return to the center stage of racing if the rules and kit roll out is handled correctly and fairly. Cotman worked wonders with the DP-01 in 2006 and 2007, I am sure he will do a great job with our new car in 2012.