Dale Coyne Racing’s Sebastien Bourdais says improved cockpit cooling is the last significant hurdle to clear for IndyCar’s new-for-2020 aeroscreen.
Conducted under a sweltering Florida sun on Tuesday, the Frenchman was tasked with sampling the protection device designed by Red Bull Advanced Technologies for the first time while trying new pieces and ideas to increase airflow delivery into and out of the cockpit.
“It was typical Sebring humidity and 90 degrees,” Bourdais told RACER. “As expected, if you run the thing stock, with no vents open, it’s barely bearable, heat-wise.”
The tropical conditions that met Bourdais and IndyCar’s engineering team at Sebring International Raceway on Tuesday presented a worst-case scenario to manage.
“We tried all the vent configurations, and really, what makes it bearable and usable for heat and body comfort is a vent on the side of the aeroscreen that plugs into the helmet,” he added.
The aeroscreen’s primary cockpit ducting system is found where the RBAT unit meets the revised shock cover, which funnels air below the screen and towards the driver’s upper torso and helmet. In prior tests conducted by Team Penske, Chip Ganassi Racing, and Andretti Autosport, concerns over insufficient airflow strength through the main vent were noted, with the need for direct cooling to the helmet serving as the most common recommendation.
Determining the correct sizing of the NACA duct that will feed air to the helmets could be the last item for IndyCar to complete as RBAT moves towards mass aeroscreen production.
While working through the various cockpit cooling ideas presented at Sebring, Bourdais and fellow aeroscreen tester Patricio O’Ward from Arrow McLaren SP tried running with their visors open and closed, at high and low speeds, to observe the changes in airflow aimed at their helmets.
Inside the No. 18 DCR Honda, Bourdais watched in fascination as his cockpit became a miniature wind tunnel.
“The air would come in at the front, but then get sucked out from the top right away,” he said. “The air that comes in goes up and stays close to the screen, but then it stalls close to the driver, so it doesn’t really reach you.
“The air just kind of tumbles in front of your face, which makes it hard to run with the visor open at speed because there’s this ball of dust and debris that floats in front of your face and gets in your eyes. At low speed, like simulating a yellow flag situation behind the pace car, it’s fine, but at high speed, it isn’t.”
Bourdais enjoyed a few laps of science fiction taking place a few inches in front of his helmet during one test run.
“It was like a movie when they’re in outer space with no gravity,” he continued. “They wanted to try putting me up or down at different heights for me in the car to see how that affected things with the airflow, so they modified my seat. The seats are made from the little [foam] beads, and there were some of them that got loose and started floating in the car during that run.
“I did two laps with this little sphere of beads, like, perfectly levitating in front of my eyes in that dead zone of stalled air. It was a pretty crazy thing to watch!”
Having been impressed with the visibility offered by the aeroscreen, Bourdais is confident the steamy ambient conditions at Sebring gave IndyCar and RBAT all they need to finalize a range of cooling options for the new season when it commences in March.
“You aren’t going to see us race in something much hotter than what we had today,” he said. “I think they came away knowing what to do so we can handle worst-case situations. With a lot of heat, it isn’t as pleasant to drive as before without the screen, but it can be made better.”