McLaren MP4-25 - front chassis duct / rear aero package 13 March 2010
Ever since the car's launch, the MP4-25's sophisticated aero package has attracted a lot of attention. The airbox is split into two channels. The lower one (bottom blue arrow) is designed to cool the gearbox radiator. The hot air expelled then hits the exit edge of the lower beam wing and diffuser (see small red arrows). The upper channel (top blue arrow) feeds air through the long fin that connects to the rear wing. The air is then expelled on to the wing's flap through a slot at a certain speed. These two processes combine to stall the rear wing at high speeds, reducing drag and hence increasing maximum speed. There is a clever solution to control the system. A duct has been placed at the front of the chassis, which feeds additional air into the process, over saturating it and stopping it functioning. On the straights, where this solution is most important, the drivers have the ability to close the duct with either their left leg or arm.