Drag Reduction System

The Drag Reduction System (or DRS) is a form of driver-adjustable bodywork aimed at reducing aerodynamic drag in order to increase top speed and promote overtaking in motor racing. It is an adjustable rear wing of the car, which moves in response to driver commands. DRS often comes with conditions, such as the pursuing car must be within a second (when both cars cross the detection point) for DRS to be activated.

DRS was introduced in Formula One in 2011. The use of the DRS system is an exception to the rule banning any moving parts whose primary purpose is to affect the aerodynamics of the car.

The system is also used in the Formula Renault 3.5 since 2012 and Deutsche Tourenwagen Masters since 2013. An adjustable wing was also used by the Nissan DeltaWing at the 2012 24 Hours of Le Mans, although with free usage.

In Formula One, the DRS opens an adjustable flap on the rear wing of the car to reduce drag, thus giving a pursuing car more speed and thus a greater chance of overtaking a car in front. The FIA estimate the speed increase to be between 10–12 km/h by the end of the activation zone. When the flap is closed it creates more downforce giving better cornering.

The device can only be used during a race once two racing laps have been completed, and when the pursuing car enters a designated "activation" zone defined by the FIA.

In 2011, the FIA increased the number of DRS zones to two on some circuits featuring multiple long straights. In Valencia and in Montreal, two zones were endorsed on consecutive long straights, whilst in Monza and in Buddh, two zones were created on separate parts of the circuit. Two zones had originally been planned for every race with multiple long straights from Montreal onwards (depending on Montreal/Valencia success), but such plans did not materialize. However, at the penultimate round of the 2011 season, two zones on consecutive long straights saw a return at Yas Marina.

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