What is a 'snap of oversteer' in Formula 1?

You hear it all the time – “…and he had a snap of oversteer…” or a “…big snap of oversteer….”, sometimes a “….BIIIIG snap of oversteer!” especially if you’re watching the excellent Karun Chandok or one of Jolyon Palmer’s brilliant dissections of matters on-track.

As you watch the replay you’ll see the car wiggle, and on the in-car video you may notice the driver wrestling with the steering wheel, but what is this oversteer, and why is it a snap? Is oversteer even measured in snaps? Here’s a really brief explanation:

A snap of oversteer is when the rear tyres lose grip relative to the front so the driver needs to take corrective action which slows the car and takes it off the ideal racing line, which means a slower laptime. It’s called a ‘snap’ as the car very quickly deviates, or ‘snaps’ out of line.

Now for the detail. I’ve explained it all in the video below, but in brief here’s a text version, and this is a simplified explanation that doesn’t go into tyre slip angles because if you understand that you won’t need to read this post 🙂

An F1 car should be gripping the track more or less equally with the front tyres and rear tyres.
Now imagine a vertical pole through the centre of the car.
When the rear tyres have less grip relative to the front tyres the car will start to rotate around that pole. The back of the car tries to overtake the front; the front tyres have enough grip to go around the corner, the rears do not so they try and go straight instead of following the corner. Imagine driving around a corner and suddenly your rear wheels are on ice. This is oversteer.
Unchecked, or not checked quickly enough, this leads to a spin as you’ll see from Bottas in the video.
The solution is to ensure the steering wheels are pointed where the car needs to go, which is not where the car’s body is pointing. In the video, you’ll see Alonso on a right-hand corner dealing with oversteer. Normally the steering wheel would be turned to the right…but he has turned it to the left whilst the car is turning right. That is because he’s pointing the steering wheel where the car needs to go, not where the car is pointing. F1 drivers are very, very good at detecting and correcting oversteer, and in fact do it all the time as Sainz shows later in the video. Oversteer often beneficial, and is only a problem when there is a lot of it so the car is appreciably sliding. How much is too much? Impossible to say, best thing to do is wait for Karun to say “snap of oversteer”, and then you’ll know 🙂
That’s steering, now what about brake and accelerator? Well, what you do with that is situation-dependent, but generally you “fix the foot” which means whichever foot got you into trouble, you change it. So if you got oversteer under braking, you would fractionally reduce the braking, restoring a little more grip to the rear wheels, and if under power, you’d reduce the throttle input, demanding a little less grip from the rear wheels.
So now the car is turning right, with the steering wheel left. This is also known as an “opposite lock correction” as you are turning the steering wheel opposite to the car’s cornering direction.
Some people say an oversteer correction should be “turn into the skid” but that’s not good advice in my view as it’s not clear which way “int the skid” is, and you may need to correct oversteer before a true skid situation arises, and how far do you turn? If you simply think of car control as “keep the steering wheels pointed where you need to go” that’ll work just fine. Look in the video for Alonso having a second oversteer moment through the gravel trap.
Okay, now the correction has been done, and hopefully the car will swing back into line which requires an extremely quick unwinding of the opposite-lock steering correction. This is what catches out many amateur drivers who haven’t learnt how to do rotational steering and cannot unwind the correction properly or quickly enough, so end up swinging violently the other way. You can see examples of that in my oversteer recovery video below.
If all goes well, and you’re not backwards into the armco, then now you need to “gather the car up” (c), Martin Brundle, and get on with to your lap. Typically a decent Snap of Oversteer, or a BIIIG Snap of Oversteer will have required some track space to recover, and then some. As you saw, Alonso needed to go off the track to find the space to complete the recovery.
It is important not to wrestle the back immediately on line, often better to let the car go wide, off the track and ease it back on. That is because a quick direction change could lead to further grip problems. Grass, gravel and kerbs have a lot less grip that nice smooth tarmac, and the tyres could pick up gravel etc further reducing grip.

That’s the basics of oversteer in F1. Now a few more points:

An oversteery car is one where you need little steering input before it turns into a corner. I think Jackie Stewart said you “use the steering wheel to introduce the car to the corner” and then it rotates in by itself, and that makes for a really agile, and therefore quick racing car. But, it’s also hard to drive, so there’s a balance. Roadcars like the ones we all own, even sports cars, are set up for understeer so they tend not to respond as quickly to steering input but that’s safer for drivers who aren’t lining up on a Formula 1 grid. One thing sports car owners may do is change the wheel alignment settings to get more of an oversteery car, or less understeery, but that becomes more challenging to drive and can be tiring on long cruise drivers.
An oversteer episode might be known as a “moment”, which a period of time of a couple of seconds on a racetrack when you are staring disaster right in the face. Some say “moments” are brown-trouser affairs, but they’re usually over so quickly there’s no time to be scared at the time. This is why you need to develop car control skills to the point you can recover oversteer without thinking about it, similar to how you’d withdraw your hand from touching a very hot surface.
When the car oversteers the driver needs to make an instinctive decision as to whether to try and recover the car as described above, which is known as a “save”, or abandon any attempt which could make things worse. Let’s say the back end rotates around so quickly no amount of corrective action will recover the situation. What you need to do then is slam the brakes on hard as you can, and generally the car will slide in the direction it is travelling, and that often means into a gravel trap. If you don’t slam the brakes on hard the car could spear off the track at any direction and that often means into a barrier. You can see examples of that in the oversteer recovery video below.
F1 cars have very soft tyres, even the hard compounds, so when the brakes are locked and they are sliding then the tyres are effectively sanded from round into round plus a flat spot, a bit like cheese on a cheese grater. In the video you can see Bottas’s tyres smoking…that’s the conversion from round to flat on the bottom. He would have destroyed those tyres as a result. This is less of a problem with roadcars as we run much harder tyres which don’t get destroyed as easily, and we don’t enter spins at 300km/h.
F1 cars rely on aerodynamics for a lot of grip, and that means the car needs to be pointing straight. In oversteer situations the car isn’t straight, it’s sliding sideways, even if recovered, and that hurts aerodynamic downforce and therefore grip, complicating the driver’s job of recovery.
F1 cars have limited steering lock – see in the video Max goes to full lock to recover, and that’s only about 200 degrees. Compare that with my Lotus Elise recovery where I turn the steering wheel more than 360 degrees to recover. F1 drivers don’t need to use the rotational hand-over-hand steering technique as the car simply doesn’t have that amount of steering lock.
If you’re really skilled, like Max, then you might partially spin, lock the wheels, and if the car’s nose comes around you can release the brakes and carry on. This is a super advanced technique and I would suggest if you spin locking the brakes until you are stopped. You can see my 360 spin in my Lotus as another example.
Now how much oversteer is a ‘snap’ of oversteer? Well, we have metres, grams, degrees, newtons, kilograms and other standard units. There is in fact a measure of oversteer which is relative tyre slip angles, but there is no fixed definition of a “snap”. I think we can loosely say that a “snap of oversteer” is when there is enough oversteer that the driver’s corrective action slows the car. A big snap? That’s when Karun’s voice rises. And beyond that, when he stresses the I in BIIIG, then that’s a lot of oversteer. I think the unit of oversteer should be a Snap, measured in Chandoks.

Okay, that should be “snap of oversteer” explained!