how drafting behind another car makes it easier to overtake.



how drafting behind another car makes it easier to overtake.

In: Physics

You get less air resistance behind the car meaning you don’t have to waste a lot of power. That is all I know and anybody correct me if I am wrong

When drafting you’re behind a car. The car in front is taking the brunt of the air resistance thus slowing it down. The car behind gets little to no air resistance meaning it can typically go faster. Once close enough, the extra power not hindered by the air can be used to slingshot past the car in front

When a car moves fast it needs to push all the air out of the way. This means that there is less air behind the car creating a low pressure area behind it. The car that follows will then have to push less air out of the way as the lower pressure creates less air resistance. It is therefore easier for the following car to speed up and this extra speed can be used to overtake the car in front. This is often refered to as a slingshot manouver where you place your car just far enough behind the car that you gain a noticable effect from the reduced drag and then speed up as much as you can without hitting the car in front before you swirve out to the side and let the extra momentum from the speed carry you past the other car allowing you to overtake.

A disadvantage to driving behind another car, especially in NASCAR where the simple track layout and the strict specifications for the car means a lot of cars are stuck behind each other, is that the lower pressure air means the cooling is less efficient. So the following car tends to overheat more then the car in front. So sitting behind another car for long, even though it saves fuel, is not sustainable and you need to do things to protect your engine from overheating. Another issue which is mostly present in Formula 1 is that the lower pressure creates reduced downforce. So the car following may not take the corners at the same speeds as the car in front. Even if they are faster in the streight sections of track the reduced speeds in the corners may make it hard to overtake anyway.

While air seems to be nothing, to offer no resistance, the faster you go the more it acts like water, pushing back against you, slowing you down (imagine trying to run in water!).

In this case the front car is doing all the work of pushing the stationary air out of the way. That slows them down. The second car doesn’t have to do that work so can go faster