Lighter, cooler aeroscreen set to debut at Long Beach

17/04/2024 15:07

IndyCar's second-generation aeroscreen will make its competition debut this weekend in Long Beach, one month ahead of schedule. Its second-generation upper frame — the “halo” — debuted in St. Petersburg.

Designed and manufactured in a partnership between Red Bull Advanced Technologies, Pankl, PPG and Dallara, the first version of the aeroscreen appeared as a mandatory driver safety device to start the 2020 IndyCar season and has prevented multiple cockpit intrusions — ranging from wheels and tires to suspension components and bodywork — since its introduction.

Although the aeroscreen has taken IndyCar driver safety to unparalleled heights, the device's combined weight of nearly 60 pounds with the titanium halo from Pankl, the 9mm thick PPG laminate screen, plus its chassis mounting frame, has contributed to the Dallara DW12's heft.

The use of the screen in front of the halo has also been an ongoing contributor to heat management issues in the cockpit due to the limited amount of onrushing air reaching the drivers, who also sit between the engine's oil and water radiators which transfer an exceptional amount of heat into the cockpit.

With weight and driver cooling as the clearly defined areas to improve, the second-generation aeroscreen has undergone key developments to address both areas. Thanks to a new manufacturing process developed by Pankl that requires less material, the weight of the titanium halo has been reduced by nearly seven pounds — 6.8 to be exact. It's a reduction that will benefit the field for years to come.

The new 6mm aeroscreen from PPG, which was originally meant to go live at the May 10-11 race on the IMS road course, will be used exclusively on road and street courses. IndyCar's 2020-spec 9mm laminate, will stay in service for the Indianapolis 500 and all remaining ovals with no alterations.

The first-generation laminate offers immense strength and is perfectly suited to handle oncoming objects at speeds of 200mph or more on big ovals, but that thickness and its related weight has been more than what the project partners have deemed as necessary for the slower road and street circuits.

As a result, a thinner laminate, which is the same thickness used for the windscreens found on IMSA's GTPs and LMP2s, was commissioned by IndyCar. In moving from nine to six millimeters, and the removal of a heating element — a defroster inserted in the sandwich of laminate plies that went unused — PPG has created a new screen that takes another 4.3 pounds off of the car.

In combination with the new halo, 11.1 pounds are spared from atop the cockpit at places like Long Beach and next week's trip to the Barber Motorsports Park road course in Alabama. (Previous weight loss figures supplied by the series placed the second-gen halo at -7.2 pounds and the second-gen laminate at -5.5 pounds, but both figures have since been adjusted by IndyCar.)

Despite the beachside unveiling for the freshly vented laminates, temperatures aren't expected to be high in Southern California, but if that changes, the new openings near the top of the aeroscreens and their associated ducting that extends into the cockpit are capable of feeding a lot more air onto the drivers. Only the 6mm aeroscreens will make use of the top vents.

Six drivers tested the prototype version of the revised aeroscreen and were pleased with the top cooling vents; a third vent was tried towards the base of the screen which drivers reported as having a minimal influence on cooling and was not incorporated into the final design.

The new cockpit ducts on the backside of the top vents are 3D printed using a bioplastic named PA11, which has rubberized properties that will hold its form while funneling air into the cockpit but is soft enough to collapse if a driver's hand were to come in contact with the ducts during a crash. The unique material is produced from castor beans.

In trading the smooth profile of the 9mm oval aeroscreen for the vented second-gen 6mm version, airflow around and over the laminate has been mildly disrupted. A modest loss of 35 pounds of downforce at the rear of the car is what the series has measured.

"It has a small effect on the rear wing," Tino Belli, IndyCar's director of aerodynamic research, told RACER. "One of the teams said it was actually quite hard to measure for sure what the loss in downforce was, but they did notice that the aero balance went forward, which made them believe they’d lost some rear downforce. But in the data, they found it difficult to see loss in downforce, so that’s good."

Although it might be tempting for teams to recover the 35 pounds of downforce by covering the vents, Belli says it won't be permitted by the series.

"We’re not going to allow them to blank it off," he said. "It will only be accepted to do so in the rain with blanking panels. But the small loss means we're able to run with these open without negatively affecting the aerodynamics."