What Car? Q&A - Do ABS take longer to brake?

Q: I understand that anti-lock brakes (ABS) are useful in assisting the driver to retain control when negotiating a hazard while braking. Is it true that it adversely affects the stopping distance in a straight line as it releases and reapplies the brakes?
David Wright

A: You are correct, theoretically a car can stop in a shorter distance if it is not fitted with ABS. However the benefits of ABS, or anti-lock braking system, far outweigh this shortfall.

ABS detects if one or more wheels has stopped rotating and is starting to skid, so it decreases the amount of force applied to the brakes, allowing it to rotate and slow the car down. When the wheel has regained traction the system increases the braking force to the point when traction is lost and the process repeats itself. In emergency situations, when maximum braking force is required, the ABS system can engage and disengage the brakes several times a second.

This action does increase the stopping distance of the car, but it allows the driver to steer the car away from danger in the moments when the wheels are allowed to turn. It also helps in situations where a driver ‘panic brakes’, applies full brakes and enters into a skid.

An experienced driver should be able to stop a car without anti-lock brakes in a shorter distance if they could apply maximum brake pressure, without losing wheel traction. There are also some extreme situations, such as driving on ice, where ABS is not desirable. However, for the majority of drivers, in the majority of situations, ABS is a safer option. There are only a handful of cars on sale in the UK which don’t come with ABS as standard.