Slipstream overtaking

Picture this scenario – you’re competing in a race series with identically powered cars and you’d like to pass someone on the straights – how do you do it?

There are several techniques which could be used, and ideally combined. One of which is driving a better line to exit the corners faster, or braking later, but here we’re going to take a look at ‘drafting’ or using the ‘slipstream’. Behind a moving car, there is an area of turbulent air which is at lower pressure than the surrounding atmosphere. This low pressure zone can be exploited to maintain the same speed of the car in front while using less energy. Exploiting low pressure zones can be highly effective, it’s how aircraft wings and sails work and why geese migrate in a v-shape.

Using less energy to maintain the same speed means you’ll have some spare performance on tap, which can be used to overtake your rival. 

We would never lie to you, but just to prove it exists let’s take a look at the slipstream in action with this cycling speed record attempt – skip to the middle bit.

The size and usefulness of the slipstream depends on how fast you’re travelling, and the shape of the car in front. In general, the more aerodynamic, the less effective drafting will be – but you can use this technique with any car. To exploit the low pressure area you will need to be quite close, which is obviously a risky place to be as you approach a corner – at some point they will hit the brakes hard and for this reason the technique is used the most on long straights. 

Watch this incredible overtaking manoeuvre as Lewis Hamilton exploits the slipstream to gain the dominant inside line on entry to the corner, brave but risky.

 As you approach the slipstream of a car in front, you should be able to maintain the same speed with slightly less throttle than your opponent. To overtake, you’ll need to use full throttle at the opportune moment, and then use this burst of acceleration to gain momentum then pull out and around the car ahead. Just like Hamilton you can use this advantage to grab the dominant line and nudge ahead one position.

A word of caution – if you in a car equipped with downforce, while you’re in the slipstream the low pressure will temporarily reduce the amount of grip available which can lead to understeer, crashing and crying.