Handbrake turn

The handbrake turn (also known as the bootlegger's turn) is a driving technique used to deliberately slide a car sideways, either for the purpose of quickly negotiating a very tight bend, or for turning around well within the vehicle's own turning circle.

The driver starts by using steering input to transfer weight to the outside tires; the handbrake is then used to lock the rear wheels, thus upsetting the adhesion between the tires and the road surface. With practice, the car can be placed accurately by releasing the handbrake and accelerating the vehicle. The technique is used in some forms of motorsport, for example rallying, autotesting, drifting and motorkhana.

Many sports cars, especially English makes such as MG and Triumph, as late as the early 1970s were offered with a fly-off handbrake option for competition purposes—the button on the end of the lever has to be pressed before the brake will lock on, which is the reverse of the normal arrangement—allowing for faster and more controlled application in a handbrake turn, and less liable to be accidentally locked on while doing such a maneuver.

In a rear-wheel drive manual transmission vehicle, it is also necessary to operate the clutch to prevent the handbrake from stalling the engine.

In a normal turn, rear wheels follow the front ones because resistance in the forward direction (i.e. where the wheels turn) is significantly less than in the sideways direction, and the latter provides the centripetal force that makes the rear end of the car follow the turn. When the driver locks the rear wheels with the handbrake, both directions have the same resistance, so the rear end tends to keep moving in the original direction (inertia) and, thus, slides out.

Handbrake turns are primarily a technique used to negotiate tight turns in motorsport but can also be used in certain other applications such as stunt or pursuit driving.

For stunt purposes, parallel parking can be completed in a single motion using the handbrake. This technique is often demonstrated at car shows, demonstrating the vehicle's agility and the driver's control.

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Wikipedia