To increase lateral and longitudinal grip capability by raising the normal load on the tires with downforce-producing devices, and to feed the powertrain heat exchangers with a predictable, sealed flow of air while limiting the drag cost of doing so. The subteam owns every external surface of the car: front wing, rear wing, undertray/floor, bodywork and nose, ducted sidepods, and (from CR26E) side aero. It also owns the air-side of cooling: sidepod inlets, ducts, shrouds and fan integration. Heat rejection hardware itself (radiators, pumps, lines) belongs to Powertrain; Aerodynamics owns the flow path that feeds it.
- Meet the aerodynamic contribution to the vehicle points goal. A minimum L/D of 2.0 is required for a downforce device to be a net points gain; mass sensitivity was 0.36 points/lb on CR25 and 0.56 points/lb on CR26I. CR22 set that rule: its OpenLap point mass sweeps put the cost of mass at 0.482 points/lb, showed an efficiency of at least 1.5 to 2 is required before any downforce device pays for itself, and the subteam aimed for 2.5 to 3. - Maintain or improve CLA and CDA year over year without adding mass. CR26I: designed CLA 4.22 / CDA 1.44; validated 4.16 / 1.55 at 34.77 lb, a 32.9% CLA gain over validated CR25 for a 1.5% weight reduction. The step change was CR22, the first car with an undertray: CL went from CR21's -2.01 at L/D 1.66 to -3.51 at L/D 2.68, on the same 1.1377 m^2 reference area, against a goal of CL -3.0 at L/D 2.5. - Hold longitudinal aerodynamic balance (center of pressure) in the 40-50% front loading window so the platform stays predictable. CR26I designed 50.1% front, tested 48.3% front. - Contribute to a stable and predictable platform in dynamic conditions: design to worst-case heave, pitch and roll so nothing scrapes. - Validate CFD against real-world testing every year. CR26I: CL error 1.09%, CD error 3.38%, CoP error 4.79%. The baseline came from constant speed and coast down testing on CR21 in early fall 2022, straight line only: CFD gave CL 2.01 and CD 1.21 against experimental -1.971 and 1.344, so 1.94% error on CL and 9.98% on CD. Known CFD fidelity is 2 to 10% between runs and against real world data, which is the bar a design change has to clear before it counts as a gain. - Improve integration with Chassis, Suspension and Powertrain early, in the design phase rather than during assembly. - Reduce manufacturing time and consumables each cycle. CR26I moved undertray to a single vacuum infusion and moved molds from 3-axis CNC to a 5-axis gantry.