32 replies to this topic

[THE "driverider"]

Martin Brundle mentioned that on this seasons calendar it is the Shanghai Hairpin, but has there been a higher amount of g-force under braking; Fuji Speedway perhaps?

[d246]

Martin Brundle mentioned that on this seasons calendar it is the Shanghai Hairpin, but has there been a higher amount of g-force under braking; Fuji Speedway perhaps?

Turn 1 Monza?

[Lights]

Turn 1 Monza?

I think the g-forces are lower here because of less downforce and a longer braking zone

[Ali_G]

Turn 2 at the A1-Ring would have been very heavy braking considering you are braking while travelling uphill.

[Neophiliac]

Should happen on a high to medium downforce circuit with a high asphalt grip and softest rubber used. It doesn't really matter what corner follows the straight: the G- forces will be the highest at the start of breaking - since when the speed scrubs off, the downforce falls and so does the tyre grip.

Street circuits are disqualified due to low grip surface, and so is Hungary for the same reason. Newest tracks would be the best bet. Maybe Korea or Abu Dhabi (I know the latter wes built with high-grip asphalt).

[KirilVarbanov]

Canada -6.1 ?

[Ross Stonefeld]

It would be the corner that has the most amount of downforce on entry, wherever that is.

[Dunder]

Shanghai T14.

Cars are in medium downforce configuration which aids braking compared to corners with a higher speed entry (like Monza T1).

[DrProzac]

I think the g-forces are lower here because of less downforce and a longer braking zone

On other hand downforce increases with the square of speed, so the bigger the speed they're braking at, the bigger the downforce wich increases the potential deceleration. But you're probably right.

Car traveling at 350 km/h will have about 1/3 more downforce than a car traveling at 300 km/h. The low downforce setup has to have 3/4 of the lift coefficient of the high downforce setup to make it even.

Edited by DrProzac, 19 April 2012 - 17:21.

[bauss]

It would be the corner that has the most amount of downforce on entry, wherever that is.

and the one which is uphill

is turn 1 at Korea, uphill? If so, it could be

[Brandz07]

and the one which is uphill

is turn 1 at Korea, uphill? If so, it could be

I think you've got turn 1 confused with turn 3

[Baddoer]

Korea T3 and Abu Dhabi T8 could be there too
oh, and Bus Stop

Edited by Baddoer, 19 April 2012 - 18:26.

[Brandz07]

Korea T3 and Abu Dhabi T8 could be there too
oh, and Bus Stop

Not sure about the bus stop, it's right after a high speed turn which will lower the speed they're travelling quite a lot.

[Baddoer]

Not sure about the bus stop, it's right after a high speed turn which will lower the speed they're travelling quite a lot.

Maybe you right
i've got this where Alonso brakes at about 310kph, but without DRS, so it could be a bit more in Q

[Sardukar]

Not sure about the bus stop, it's right after a high speed turn which will lower the speed they're travelling quite a lot.

that corner is taken flat out, dont really wash of much speed

[Brandz07]

that corner is taken flat out, dont really wash of much speed

But compared to other straights we're talking about, it's still enough of a turn to be slower and therefore less G in the end.

[Baddoer]

Another videos:
search "Rosberg onboard Spa 2011" - Rosberg brakes at 317kph into bus stop
"Hamilton Onboard Korea 2011" - 314 kph into T3
"Vergne Onboard Abu Dhabi 2011" - 321 kph into T8

[Lights]

On other hand downforce increases with the square of speed, so the bigger the speed they're braking at, the bigger the downforce wich increases the potential deceleration. But you're probably right.

Car traveling at 350 km/h will have about 1/3 more downforce than a car traveling at 300 km/h. The low downforce setup has to have 3/4 of the lift coefficient of the high downforce setup to make it even.

I used simple logic, your explanation is too much knowledge for me. But thanks

[Lights]

We're mainly thinking about slow corners after long straights, but if you look at g-forces, they're coming from all directions.

Wouldn't T9 in Bahrain have a higher g-force load? It has a lot of lateral movement but on the other hand, it's going downhill.

Or T10 in India. The braking is short but it flows uphill into a fast corner.

[bauss]

I think you've got turn 1 confused with turn 3

could be turn 1 , 3 or 4....long as they reach max speed b4 the braking points... the corner with the most elevation will probably make for shorter braking distance, which means higher g force.

Also if its a headwind, higher g force.... I dont think its a given that any one corner produces the absolute highest

[KmR]

Steve on Speed mentioned it last week, too. He said the Shanghai hairpin has the highest g-force up to 6g. But I somehow can't images that. I always thought T1 in Monza would be a favorit for the highest g-force.

[Neophiliac]

We're mainly thinking about slow corners after long straights, but if you look at g-forces, they're coming from all directions.

Wouldn't T9 in Bahrain have a higher g-force load? It has a lot of lateral movement but on the other hand, it's going downhill.

Or T10 in India. The braking is short but it flows uphill into a fast corner.

The question was for highest g-forces under braking.

In general, any lateral movement will make less traction "points" available for braking. If you are braking and turning at the same time, your aggregate deceleration will be a vector of the two forces. For simplification, let's say you decelerating at 2g and also moving sideways at 90-degree angle (this is the simplification, because it's never really 90 degrees) generating 2g. That would give you a 45-degree vector equal to SQRT(2^2+2^2) = 2.82g. Traction dynamics are complicated here, but I think it's fair to say that an angled deceleration like that is never going to give you the highest possible g-forces overall, as you have multiple adverse effects working against it: 1) the yaw of the car should reduce downforce since the air is not moving directly perpendicular to wing surfaces 2) the rear tyres (because they do not turn) are not moving in quite the same direction as they are rotating which means less overall traction.

All of that is to say that the fastest way to stop is in a straight line, with all four wheels pointing in the same direction. Going uphill and some headwind would definitely help too.

You are correct that we should not be looking at the slow corners, however: - by the time you get down to 80kph, you are no longer decelerating at highest Gs. What we're looking for is (1) high overall mechanical traction available based on track surface and tyres used, (2) high speed at the start of braking zone, (3) medium to high downforce configuration (this trades off against (2) and (4) bonus points going uphill.

If turn 3 at Korea is indeed uphill, I'd definitely go with that one.

[MichaelJP]

Interesting though that no matter how extreme the braking deceleration in F1 (and 6g must feel awesome) it is distinctly unimpressive to watch from the incar view.

Actually being there trackside is a different matter though, you can really sense it then.

[Ross Stonefeld]

Steve on Speed mentioned it last week, too. He said the Shanghai hairpin has the highest g-force up to 6g. But I somehow can't images that. I always thought T1 in Monza would be a favorit for the highest g-force.

Turn 1 at Monza would have the lowest downforce of the year.

[KmR]

Sure it has but I think that the g force is nevertheless pretty high, isn't it?

[Ross Stonefeld]

A car at 190 with medium to medium-high downforce will have more braking ability than a low downforce car at 215. So at the moment the back straight at China seems to be the perfect combo of straight speed + wing level.

[Dan333SP]

Having DRS certainly helps, because the cars might run Shanghai in a medium to high downforce configuration but with the DRS open on the back straight it's effectively like running a low downforce setup until it snaps shut at the braking point and adds all that downforce to the deceleration.

[Ross Stonefeld]

The other thing is these ultra-high G's are only for a fraction of a second. They spend very little time braking, maybe 2 seconds for the hairpin in China, and you only have that downforce when you first hit the brakes. So 6gs at 200mph. Less at 175, even less at 150, etc.

[Dunder]

Interesting though that no matter how extreme the braking deceleration in F1 (and 6g must feel awesome) it is distinctly unimpressive to watch from the incar view.

Actually being there trackside is a different matter though, you can really sense it then.

TV doesn't do these machines justice in many respects but the sheer violence of an F1 car under hard braking is something that has to be seen 'in the flesh' to really grasp what is going on.

[HoldenRT]

Nico Rosberg said it's the highest (China) with 6G.

[thegforcemaybewithyou]

I made some simple calculations after i first read this thread.
Just go through it from top to bottom and you'll see what i did there.
If there are any questions or maybe you found an error, then please give some feedback!

Here's a screenshot:



If you could provide better estimated values for engine power, the car's cross sectional area, downforce at certain speeds and friction values of the tyres for the 2012 cars,
then i could calculate a theoretical maximum gforce

What can you learn from these calculations?

1. the highest gforces are only possible at highest speeds and at the very beginning of the braking because only at this point the car brakes at almost 1G only due to drag caused by the air and tyres are additionally pushed down at the track by the downforce
2. f1 brakes are extremely powerful
3. math sometimes is fun

[Zauba]

6 Gs of latteral acceleration was already recorded in Suzuka's 130R and Barcelona's Campsa.

So, the highest G-Force under braking is around that value

[Nigol]

6 Gs of latteral acceleration was already recorded in Suzuka's 130R and Barcelona's Campsa.

So, the highest G-Force under braking is around that value

This is not true.