Two new components designed and provided by Dallara will be incorporated on the DW12 chassis for the upcoming IZOD IndyCar Series, the sanctioning body announced Tuesday.
The chassis manufacturer has designed structural pieces for the sides of the monocoque with the goal of further reducing the risk of cars potentially rotating on side impact. To improve durability, brake disc guards will be mandatory for oval races and optional for road and street course events.
"It is important that we continue to evolve the chassis based on the data gathered to further enhance performance and safety," said Will Phillips, vice president of technology for IndyCar. "We were extremely pleased with the performance of the new car last season and continue to study data and feedback to improve the car."
The side impact structures, which are mandatory for the 2013 season, are bolted to the sides of the cockpit at driver's shoulder height and fit inside the bodywork. They are not visible outside of the car and have no aerodynamic effect. Based on its design to prevent interlocking wheels, the underwing is the widest part of the car, which is unique in open-wheel racing.
"When the underwing contacts the wall, we want to achieve a progressive crush to dissipate the energy as it reaches the tub," said Andrea Toso, head of research and development for Dallara. "The design of the underwing therefore includes some localized weak points, which fail at specific and progressive impact loads to achieve the desired dissipation. Based on information gained from some practice week incidents at the Indianapolis Motor Speedway in 2012, we decided to modify these weak points.
"For Indy, we added slots in the support cones for the underwing, and prior to Fontana we added slots in the leading edge of the underwing. These modifications have made the underwing collapse more progressively in a side impact, resulting in less load being transmitted to the driver."
Toso noted that incorporating side impact structures complements the 2012 modifications. Additionally, the carbon fiber cockpit is reinforced with Zylon panels.
"In order to further reduce the risk of tilt, we needed to get a more even distribution of crash resistance from top to bottom. This is the purpose of the side impact structure," Toso added.
Dallara also has introduced brake disc guards that are more robust and heat resistant than the 2012 model.
"The guard helps keep the rotors, which are made of carbon, from being damaged by the wheel during a typical 6-second pit stop for tires," said Phillips. "We have made it mandatory for the ovals only this season to ensure there is no aerodynamic advantage of running the old versus new type. This will allow our teams to run through their remaining inventory from 2012 at road and street events with no compromise of safety or performance."