MW - HK brakeing distance

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FW17
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Joined: 06 Jan 2010, 10:56

MW - HK brakeing distance

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Till date i assumed that the differance in the brakes of the front running redbull is no differant from that of the a lotus as they are completely procured from either a brembo or carbon industries.

The distance required for slowing an f1 car from 320kmph to about 90kmph as required for turn 12 at valancia is about 120m. In which case why was HK braking point 80m earlier than MW.

What happened at turn 12, the differance in cornering speeds at turn 12 cannot be more than 10kmph

Did MW miss his braking point?
Are the brakes in lotus so bad?
or are differance between fresh tyres and used once so large?

czt
czt
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Joined: 05 Mar 2009, 00:07

Re: MW - HK brakeing distance

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I can't see the difference in braking distance being as much as has been quoted, but the Lotus is likely to have a longer braking distance than the red bull.

For a start, the braking set-up is likely to be less optimised but a bigger factor may be aerodynamics. The Lotus will have a shed load less downforce that the red bull meaning that the tyres will not be able to work as effectivley at slowing the car down.

RH1300S
RH1300S
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Joined: 06 Jun 2005, 15:29

Re: MW - HK brakeing distance

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I could stick F1 brakes on my Nissan Micra and it will only stop as quickly as the tyres let it.

Lotus has a lot less grip than Red Bull, this difference is much greater at high speed due to the downforce generated.

The corner in question had a very high speed approach.

The Lotus will need to brake a LOT earlier than the Red Bull - 80m who knows, but less than half that would still be enough to catch someone out.

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FW17
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Re: MW - HK brakeing distance

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Turn 12 entry speed is about 75-85kmph, it is a sharp right hander.

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mep
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Location: Germany

Re: MW - HK brakeing distance

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Entry speed is not so important. Max top speed before you brake will affect your brake distance because it raises your amount of downforce and therefore your can transmit more braking force through your tires.
You don't even need to brake much earlier to get something slammed into your rear when the following car is still driving with ~300km/h.
It's a quite interesting topic for some calculations maybe I find some time to do so.

Belatti
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Re: MW - HK brakeing distance

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From my point of view, Weber was trying to use Kovys wake to gain speed and when he realized he was too close he atempted to move to the side and didnt have time.

Taking advantage of a backmarker´s slipstream is not really a good thing to do when you are getting close to a braking point
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siskue2005
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Re: MW - HK brakeing distance

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Belatti wrote:From my point of view, Weber was trying to use Kovys wake to gain speed and when he realized he was too close he atempted to move to the side and didnt have time.

Taking advantage of a backmarker´s slipstream is not really a good thing to do when you are getting close to a braking point
they were racing for position

Belatti
Belatti
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Re: MW - HK brakeing distance

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And?

Kovalainen is a backmarker anyway.

I did not say Weber was lapping him :wink:
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"I have no idols. I admire work, dedication and competence." -Ayrton Senna

cornermarker
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Re: MW - HK brakeing distance

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Yeah, nothing to do with braking ability. The fastest car on the grid was behind the 3rd slowest. Stuff happened, because each man was concentrating on his own race and not being cautious enough.

Heikki comes out of turn 11, and stays to the inside to let Webber by. "Go on by so I can drive my own race. I'm not racing you, but the 5 other slow cars on the grid"

Webber stays to the inside as well, for some reason. Heikki sees this, moves to the center of the track, and lifts and/or brakes. "Please go by!"

Webber follows him to the center of the track and sticks behind him until he sees Heikki has slowed dramatically. Webber was probably seeing the red mist, and trying to slip stream, the race had been baaaad up until this point for him. At that point, He tries to turn right, but, too late.

Racing incident; too guys not being considerate, considering they had no reason to be darting about the track around/following so closely... each other

Kelpster

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FW17
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Joined: 06 Jan 2010, 10:56

Re: MW - HK brakeing distance

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This post is not to point out whose mistake or inability it was for the crash.


Trying to understand the massive differance in the braking distance between the two cars.
top speed before you brake will affect your brake distance because it raises your amount of downforce and therefore your can transmit more braking force through your tires.
Both cars had a top speed of 309kmph (without slipstream)Redbull using an F-duct hence running more wing, Lotus has not ventured into this area. What will be differance in the load on the tyres on the two cars?

80m was looking to be a huge differance in the breaking area, but considering this is only about 1.2-1.4 seconds differance in one corner, it should add to 3.9 sceconds that Redbull were ahead of the Lotus in the race.

cornermarker
cornermarker
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Re: MW - HK brakeing distance

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WilliamsF1 wrote:This post is not to point out whose mistake or inability it was for the crash.
That's how it started, so I figured that's what i should respond to:
WilliamsF1 wrote:
What happened at turn 12, the differance in cornering speeds at turn 12 cannot be more than 10kmph

Did MW miss his braking point?
Are the brakes in lotus so bad?
or are differance between fresh tyres and used once so large?
What happened at turn 12 was driver error on both parts. Nothing to do with brakes.

Kelpster

Just_a_fan
Just_a_fan
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Re: MW - HK brakeing distance

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It's all down to the relative downforce levels of the two cars. The reason the Red Bull is several seconds a lap faster than the Lotus is because it has much more downforce. More downforce allows you to brake later because you can brake harder because the tyres are pressed firmer in to the tarmac.

What we need to remember is that the reduction in speed during braking is not linear. This is because although the brakes dissipate energy linearly the car's energy increases with the square of the increase in speed. Higher downforce means being able to have higher initial braking rate (say 5G instead of 4.5G) but crucially that advantage remains all the way through the braking phase. The Red Bull will also not need to lose quite as much energy as the Lotus because it's better downforce for a given speed will mean it can carry a bit more speed through the corner following the braking zone.

So the RB and Lotus start off with the same energy (assuming speed and weight are the same for a given part of the race) but the RB can reduce that energy quicker than the Lotus and can carry more of it through the next corner too. Result - the RB's braking distance is much shorter than the Lotus's.
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mep
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Joined: 11 Oct 2003, 15:48
Location: Germany

Re: MW - HK brakeing distance

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Both cars had a top speed of 309kmph (without slipstream)Redbull using an F-duct hence running more wing, Lotus has not ventured into this area. What will be differance in the load on the tyres on the two cars?

80m was looking to be a huge differance in the breaking area, but considering this is only about 1.2-1.4 seconds differance in one corner, it should add to 3.9 sceconds that Redbull were ahead of the Lotus in the race.
It is a good start when they had the same top speed before braking.
If we know top speed before braking, speed after braking and their exact braking points then it should be possible to make a rough guess about the difference in downforce those cars have.

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ISLAMATRON
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Re: MW - HK brakeing distance

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The Lotus is also heavier, and with a much higher CG, but that is probably minimal compared to the DF difference.

Scotracer
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Re: MW - HK brakeing distance

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ISLAMATRON wrote:The Lotus is also heavier, and with a much higher CG, but that is probably minimal compared to the DF difference.
The Lotus will be a max 10kg heavier.
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