17 replies to this topic

[karim marouf]

I keep reading about there being two types of modern F1 drivers: those who enter early and hit an early apex while braking, and those who do their braking in a straight line and go for the geometric apex.

I some years of club racing experience, and I understand the theory behind the friction circle and trailbraking, but I wonder if all this talk isn't just a lot of b.s. and oversimplification. I'd like to hear what people with racing experience have to say about it.

If you take an early apex, you're giving yourself an easier entry into the corner, and so of course you have more traction left over for braking while turning. But because you've taken such an easy line into the corner, the line going out is now going to be of a tighter radius than if you'd taken a latter apex. For that reason, you can't get on the gas as early or as hard. I would think that the loss of the corner exit speed would overcome any advantage gained by carrying a more speed into the corner.

I suspect that this whole idea of dividing drivers into two categories is an oversimplification. Afterall, all drivers trailbrake in at least some corners. But maybe I'm misunderstanding the whole idea behind this. I'd love to hear from people who are familiar with these techniques.

Karim

[Ross Stonefeld]

http://www.atlasf1.c...?threadid=15720

We are discussing that very topic to some extent here in Readers Comments

Ive always taken the view the best line through a corner as a general rule is that you take a trajectory that is least taxing laterally on the tires. Ie requires the least amount of steering input.

[Manson]

Braking in a straight line often leaves you too open for a dive down the inside by a competitor (depends on the corner). Depending on the track (I race ovals and they can be very different indeed from track to track) sometimes I take more of a diagonal run into the corner. It helps to try to keep more weight on the LF, keeps the door shut and unless I overshoot it badly, I can still get on the gas early. Bigger tracks with little or no braking, I try to enter high and take a late apex maximizing straight speed. I don't know how much of this relates to F1 ?

[karim marouf]

Hi Ross,

Thanks for your reply. Yeah, I got the idea for this thread from the other forum, but I didn't want to post there because most of the people weren't talking about driving techniques; they were just slagging Peter Windsor or M.S.

You say...
"the best line through a corner as a general rule is that you take a trajectory that is least taxing laterally on the tires. Ie requires the least amount of steering input"

I don't disagree at all. But I think you miss what I'm getting at. Of course the less steering you do the less you're asking the tires to do. But the idea is that you can either do more turning at corner entry and take a late apex, and therefore be able to do less turning after the apex, or you do less at the beginning and take an early apex, but then have to take a tighter line after the apex. I don't want a discussion of whether early apexing is better than late apexing. That's irrelevant since that's just dependent on the corner, the conditions, and the car's set up.

Here is a quote from Peter Windsor's article, which got me thinking about all this:

"To my eye, as I’ve said before, there appear to be two major divisions: ­those who brake in a straight line and naturally find the geometrical apex, and those who brake as they turn in to an earlier apex."
(Peter Windsor's article is at: http://www.itv-f1.co...3?mediaid=3752)

So is it really true that there are two types of drivers, those who enter early while braking deep into the corner and take an early apex, and those that do most of their braking in a straight line and take a conventional apex? Like I suspect, I believe this may be just a sports writer getting in over his head. But then again, I believe Windsor has some racing and technical experience, so I'm not sure.

[RJL]

Excellent topic!

Years ago, when I tried to be a racer, I learned to brake in a straight line, then turn in to a late apex. I've often wondered how the real boys do it. I suspect that the difference between the two described techniques gets blurred somewhat by a given set of circumstances.

Perhaps braking in a straght line and making the radius as large as possible has a theoretical advantage, just as trail braking to the apex may provide an overtaking advantage in a race situation. I imagine a driver needs both methods in his tool bag.

Interestingly, there is a very similar divurgeance of technique in bike racing between those who ride the front wheel and maximize corner speed & lean angle and those who turn the bike by spinning the rear tire and "squaring off" the corner, maximizing the drive out (making the straight longer). As in cars, both methods can be successful, the speed follows the rider.

RJL

[Ross Stonefeld]

I was under the impression every single one of them carried the brakes into the corner.

[karim marouf]

I think I've been a little unclear in what I'm getting at. When I drive, I often trailbrake (I'm still on the brakes while I begin turning into the corner), but I don't necessarily take an earlier apex just because I do. I understand that a driver can get away with heavy braking while turning into the corner because he's taking an early apex and is therefore not turning as much as if he were taking a conventional (later) apex.

My question is...how do they get away with that? Sure, they can carry more speed into the corner, but only because they've taken an easy entry line (they haven't turned the car much). After the apex, they'll have to do more turning than if they had taken a later apex, and so they won't have a good exit speed. I've always been told that the golden rule is that for most corners you go for maximum exit speed. Going hard into a corner is good for passing, but not for lap times.

In a 90-degree corner, you have to turn the car 90 degrees regardless of what line you take. But let's say you decide to take an early apex. When you hit that early apex, you might have the car turned only 35 degrees, let's say. So, because you've done less turning before the apex than is needed to make it through the corner, you'll have to do 55 degrees of turning after the apex. And for that reason your exit speed, and hence your speed all down the following straight, is going to be lower than if you'd taken a geometric apex or a late apex. Of course there are times when you want to do this, but if you did this in every corner--which is what Windsor is saying some F1 drivers like M.S. do--then I don't understand how you could set good lap times. Peter Windsor is a really smart guy and I think he was a race engineer for Williams, so what am I missing?

[PDA]

Windsor was team manager at Williams (whatever that means). I think he was there mainly as one of Mansell's acolytes.

Mansell also used the early turn in "method" and describes it in some detail in his book. I understand it to show that time to apex is quicker than the "traditional" line, but time through mid corner may be a litttle slower. Oeverall, Mansell claims (and presumably everybody else who uses the system) that time is gained. Early turn in actually reduces the distance travelled in a lap, and when you are searching for thousandths of a second, every little bit helps.

MS is quoted by Windsor in an article in F1 Racing as saying that he uses the method because up until then, he had never had a car whioch turns in crispy enough for him to stay out late, so he HAS to turn in early becasue of the deficiencies of the cars he has driven. It certainly gets him to the apex with the turn mostly done, and he can play tunes on the throttle to balance power induced oversteer out of the corner. That's what he says, not me. Byrne aslo designs a car which responds to stiff set ups which help MS get the best out of this style. It seems to be a little heavy on tyres though. Peter Wright's article in the latest Race CAr Engineering covers some of that.

An earlier article comparing MH and MS in F1 racing showed a series of photographs of the two taking three corners at barcelona (taken from head on). They show quite definitely that MS starts to turn in significantly earlier than MH 9while under heavy braking.

[Ross Stonefeld]

When it comes down to it I still view the act of driving a race car fast to be an art. Trying to explain it with science only takes away from its beauty

[GunStar]

Here's my two cents...don't anybody dare send me a penny back saying I haven't got enough upstairs.

For the straight line braking, this works best for me when I don't have anybody to fight with. I come out of the corners faster and my lap times improve. The only time I break late and into the corner, taking the early apex is when I'm attempting to overtake somebody and know they can haul it down in time, or I'm trying to keep my position...then it's pray they don't start latter than me. I've not been answered a few times and have been run off the road. Look at MS and JV. Point in case.

[tak]

There are two important considerations for the "early apex" argument--1) it is a shorter distance, and because you're going into the corner faster, you must turn in a little earlier. It is hard on tires though, and requires exceptional throttle control. Mansell talked about rotating the car on the kerb at the apex. Sounds a bit scary to me actually, but it worked for him. Ditto MS, he is able to rotate the car mid corner without compromising his drive off the corner.

Clearly the early apex is a faster way into the corner. I think it is slower mid-corner, and the same speed on the exit (highly dependant on driver skill though!). I think it is more forgiving of setup than the classic line, but harder on the tires, as the car but be rotated in the middle of the corner instead of all the way through the corner.

[Melbourne Park]

How logical is it that the early technique is harder on the tyres? If it is harder on the tyres, is this so because the brakes aborb less energy ... I think not. Possibly the tyres have extra side force on them. If there is extra side force on the wall of the tyres, is that using an element of the tyre that is not used by the straight line method? Isn't this therefor using more of the tyre, not just the wall of the tyre but also some of the across the grain element of the tyre? Doesn't being tougher on the tyres indicate more use of the tyre, which should indicate more cornering energy used which indicates faster cornering?

[RJL]

I think what Gunstar said makes sense. Brake deeper when outbraking/ overtaking/ racing. Brake earlier for lowest laptime/ qualifying. From what I remember, exit speed is crucial: the faster you are down the straight the quicker your lap. We used to recite the mantra, "slow in; fast out." Maybe this only applies in Canada?

I remember seeing splitscreen footage of Martin Brundle's feet wrt course postion during an IROC road course event years ago. He was clearly braking in a straight line, and none too deep. The guy who can brake the latest has the passing advantage but rarely does a "passing" lap result in a really low lap time.

[MacFan]

The advantage of an "early turn in / trail braking" style as opposed to the classic "straight line braking" style is that the car can be set up with more rear grip. All racing cars should be set up with some degree of understeer, otherwise any attempt to accelerate out of a corner before the lateral load is removed will result in snap oversteer. If the driver brakes while turning (and gets it right), the forward weight transfer removes the excess rear grip, resulting in a balanced 4 wheel drift into the corner. On exiting the corner, the driver still has an excess of grip at the rear, and can therefore put more power down earlier than the driver of an oversteering car, resulting again in a balanced drift out of the corner.

Turning in early with an exces of rear grip allows a later braking point, as the car's speed will be reducing all the way to the apex, and the car has more overall grip anyway. It also allows better traction at the corner exit.

[Ross Stonefeld]

The thing is though, you can trail brake no matter what your apex style

[FlagMan]

As the old saying goes - slow-in/fast out as opposed to fast/in slow out.

A good example from the 1986 Canadian GP - this being the only GP I have spectated at (as opposed to amost 25 as a marshal).

We here spectating at the Hairpin (which In those days was the last corner before the start/finish line.

During qualifying I noticed that on every other lap Senna was going very deep into the corner before turning in, the following lap he was taking a much earlier turn in. As he seemed to be the only driver doing this we started trying to figure out what was going on.

After a few laps we realised his fastest lap times where on the laps where he turned in early - and that the reason for the late turn in on the previous lap was to get a faster run out of the corner to start the timed lap.

[Melbourne Park]

Flagman:
A good example from the 1986 Canadian GP ...
During qualifying I noticed that on every other lap Senna was going very deep into the corner before turning in, the following lap he was taking a much earlier turn in. As he seemed to be the only driver doing this we started trying to figure out what was going on...

Flagman's description of Senna's racecraft reminds me of a somewhat similiar superiority in race craft that I have seen on several Grand Prix days exhibited by M. Schumaker. I have had seats several times on the Brahbam Grandstand at the Melbourne Grand Prix. The stand is at the end of the main straight, where the cars turn right and then left and then blast away on a right curve. Its the first corner after the start. The race day warm up sessions were interesting because watching the cars drive around, Schumaker's Ferrari was the only car that was doing weird things on the first corner. While the field drove the racing line through the corner, Schumaker practiced cornering from way out wide and very deep, maybe four or five times from way out wide and very deep, then he changed and practiced the absolute extreme inside line. He was the only car out there on race day morning who practiced cornering techniques based on the more likely difficult circumstances which occur just after the start when a proper line was improbable.

[MacFan]

Originally posted by Ross Stonefeld
The thing is though, you can trail brake no matter what your apex style

Agreed, every driver trail brakes to some extent. I was trying to describe the style used by Prost, Jim Clark, Mansell and others, which uses trail braking to extremes.