Driving style and fuel use

[siskue2005]

That FIA ref is out of date, the FIA allowed messages about the car systems. Have a look at the other thread http://www.f1technical.net/forum/viewto ... 35#p533035

Oh ok... thank u

[PlatinumZealot]

Hamilton's ability to save fuel over Rosberg is not insignificant either. It's in the order of 2 to 3 percent over a typical race distance. This is a significant amount in a sport which is a game of tenths. It's not just an advantage for him this season, it would be for any season as it means he can carry less fuel and therefore less weight. Imagine if we still had one of the previous season's regulations where cars had to qualify on race fuel load. Hamilton would have a small but consistent advantage not just in the race, but also in qualifying where he can carry 2 to 3 kg less fuel than Rosberg.

Interesting that you mention this. It could be a response to popular opinion that Mclaren deliberately fueled Hamilton lighter than Kovalinen to give him an advantage. It could be very well possible that Mclaren simulations showed that Hamilton could complete a stint with less fuel and they simply capitalized on that fact.

[Emerson.F]

edit: ignore that one, can´t make sense of what i thought so it´s probably wrong.

Anyway, here are Malaysia percentages,

http://i.imgur.com/BD3j3lL.jpg

He's basicly a magician. Its funny there is so little attention to the whole ERS and fuell usage in the on screen telemetry in the F1 media. I was expecting a lot more attention considering the switch in regulations of this year.

I think Lewis is using some sort of black magic (no pun intended) to use less fuel.

[condor]

Hamilton's ability to save fuel over Rosberg is not insignificant either. It's in the order of 2 to 3 percent over a typical race distance. This is a significant amount in a sport which is a game of tenths. It's not just an advantage for him this season, it would be for any season as it means he can carry less fuel and therefore less weight. Imagine if we still had one of the previous season's regulations where cars had to qualify on race fuel load. Hamilton would have a small but consistent advantage not just in the race, but also in qualifying where he can carry 2 to 3 kg less fuel than Rosberg.

Interesting that you mention this. It could be a response to popular opinion that Mclaren deliberately fueled Hamilton lighter than Kovalinen to give him an advantage. It could be very well possible that Mclaren simulations showed that Hamilton could complete a stint with less fuel and they simply capitalized on that fact.

The weight advantage of 2 to 3 kg only presents a lap time advantage of half to one tenth over a lap at most. If team mates are very close in one lap pace, such as between Hamilton and Rosberg this year, then yes it would have made a difference at some qualifyings but in general not a huge difference. The difference would likely have been more psychological with added pressure as the guy having to qualify with 2 kg more fuel knows he has to get everything just that tiny bit more spot on and conversely the lighter guy may be less likely to overdrive and make a mistake. We've seen it often so far this season where both Hamilton and Rosberg have made many uncharacteristic mistakes during qualifying simply because each is pushing the other very closely. I digress.

The main reason Hamilton was fuelled less than Kovalainen - or rather I should say Kova was fuelled more than Hamilton - is the same reason Raikkonen was fuelled more than Massa. Not because of any favouritism conspiracy but simply because they are unable to adapt their driving style to one that generates sufficient heat into the tyres for one lap pace.

So while adding more fuel for quail obviously adds lap time, they weren't able to get as much reduction in lap time by taking fuel out compared to some other drivers and hence they would get doubly hit by qualifying on low fuel because not only would they have a relatively poor starting position but then also have to pit early for fuel. So it made sense to add fuel as they were only marginally slower qualifying on heavier fuel - the increase in lap time due to heavier fuel being largely offset due to much better warm up of the tyres that a heavier car provides.

That's why in those previous seasons, Kova's and Kimi's lap times looked very competitive in relation to their team mate's when 'fuel adjusted' but the reality was that had they tried they never would have gotten close to their 'fuel adjusted' lap times because they were unable to prepare the tyres for optimum one lap pace.

[condor]

From what I understand, two traits of Hamilton's driving style are his ability to carry momentum through a corner, and his ability to manage a loose rear end (both mentioned in Mark Hughes' excellent Italian GP report).

More momentum through a corner means less fuel burned accelerating out. Loose rear end means more rear braking, more energy harvesting and greater support from ERS – which also means less fuel burned.

There are also some less 'direct' explanations. If you accept that Hamilton has a natural pace advantage, then that means he can afford to do more braking-and-coasting than Rosberg for the same overall laptime. But 'absolute pace' is one of those things that can never really be defined, so probably best to avoid those explanations.

Yes that's correct about more 'momentum' (or the more appropriate term - speed) through a corner and this is precisely due to his ability to manage rear instability. There are two particular traits of Hamilton. He barrels into a corner with high entry speed and uses a combination of a feathering release of the brakes and minute applications of throttle to alter the weight transfer so that he doesn't get too much understeer because of the high entry speed and uses his high sensitivity to feel and predict when the rear is about to let go before it does.

Let me explain. When entering into a corner, the relatively easy and textbook technique is the 'slow in, fast out'. That is, get all the braking done in a straight line, release the brakes progressively but quickly and smoothly at the last possible moment before turning in to get weight transferring from predominant front bias during the heavy braking phase back to even front/rear distribution ready for turn in. Turn in while gradually applying throttle to further get even front/rear weight distribution because the very act of turning in washes off speed i.e a deceleration where weight is transferring to the front. Apply greater amounts of throttle as the car begins to straighten up, maximising the grip available from the 'grip circle'. i.e the depiction of available lateral vs longitudinal grip e.g tyres loaded up to max lateral grip limit means no longitudinal grip (traction) available, while a car pointing in a straight line has max traction.

Hamilton generally doesn't do the above for his race laps. He gets off the throttle earlier but brakes later to keep average speed up. He then rolls off the brakes quickly but turns in with still a little bit of front weight bias i.e he hasn't completely settled the car into an even front/rear weight distribution. This is tricky because too much front weight bias will unsettle the rear and have wild oversteer on entry, while coming off the brakes too quickly will result in understeer. The trick is to come off the brakes at corner entry and initial phase of the corner to exactly counter act the weight transfer to the front caused by the natural deceleration of going through a corner. While the 'slow in, fast out' technique' settles the car before turn in and uses throttle to counteract the frontal weight transfer due to deceleration going through a corner, the 'too fast in' technique skips getting the car settled before entry and uses release of brakes rather than throttle application to counteract the weight transfer.

The negative is that it's a risky technique and easy to get wrong because the rear is being finely balanced, and because of this power can't be put down quite as early as the 'slow in, fast out' technique because the rear is unstable. This is however somewhat mitigated by the fact that the 'too fast in' technique means higher average corner speed and hence requires less throttle application to get the same corner exit speed. The fuel saving comes from the pre-entry phase of getting off the throttle earlier and braking later, and keeping a higher speed through the corner and applying less throttle on exit.

[flatlander_48]

I do agree with the idea of running slightly less wing. That reduces overall drag, and as long as you can deal with a loose car, your fuel consumption will be less. Less aero also works for Williams, but I suspect that is a consequence of how their car is designed. It is also borne out by slightly high speed trap numbers.

One other thing that no one has mentioned is that it is always helpful to avoid brake/throttle overlap. Any time the car is pulling against the brakes it is going to use more fuel.

[SuperCNJ]

From what I understand, two traits of Hamilton's driving style are his ability to carry momentum through a corner, and his ability to manage a loose rear end (both mentioned in Mark Hughes' excellent Italian GP report).

More momentum through a corner means less fuel burned accelerating out. Loose rear end means more rear braking, more energy harvesting and greater support from ERS – which also means less fuel burned.

There are also some less 'direct' explanations. If you accept that Hamilton has a natural pace advantage, then that means he can afford to do more braking-and-coasting than Rosberg for the same overall laptime. But 'absolute pace' is one of those things that can never really be defined, so probably best to avoid those explanations.

Yes that's correct about more 'momentum' (or the more appropriate term - speed) through a corner and this is precisely due to his ability to manage rear instability. There are two particular traits of Hamilton. He barrels into a corner with high entry speed and uses a combination of a feathering release of the brakes and minute applications of throttle to alter the weight transfer so that he doesn't get too much understeer because of the high entry speed and uses his high sensitivity to feel and predict when the rear is about to let go before it does.

Let me explain. When entering into a corner, the relatively easy and textbook technique is the 'slow in, fast out'. That is, get all the braking done in a straight line, release the brakes progressively but quickly and smoothly at the last possible moment before turning in to get weight transferring from predominant front bias during the heavy braking phase back to even front/rear distribution ready for turn in. Turn in while gradually applying throttle to further get even front/rear weight distribution because the very act of turning in washes off speed i.e a deceleration where weight is transferring to the front. Apply greater amounts of throttle as the car begins to straighten up, maximising the grip available from the 'grip circle'. i.e the depiction of available lateral vs longitudinal grip e.g tyres loaded up to max lateral grip limit means no longitudinal grip (traction) available, while a car pointing in a straight line has max traction.

Hamilton generally doesn't do the above for his race laps. He gets off the throttle earlier but brakes later to keep average speed up. He then rolls off the brakes quickly but turns in with still a little bit of front weight bias i.e he hasn't completely settled the car into an even front/rear weight distribution. This is tricky because too much front weight bias will unsettle the rear and have wild oversteer on entry, while coming off the brakes too quickly will result in understeer. The trick is to come off the brakes at corner entry and initial phase of the corner to exactly counter act the weight transfer to the front caused by the natural deceleration of going through a corner. While the 'slow in, fast out' technique' settles the car before turn in and uses throttle to counteract the frontal weight transfer due to deceleration going through a corner, the 'too fast in' technique skips getting the car settled before entry and uses release of brakes rather than throttle application to counteract the weight transfer.

The negative is that it's a risky technique and easy to get wrong because the rear is being finely balanced, and because of this power can't be put down quite as early as the 'slow in, fast out' technique because the rear is unstable. This is however somewhat mitigated by the fact that the 'too fast in' technique means higher average corner speed and hence requires less throttle application to get the same corner exit speed. The fuel saving comes from the pre-entry phase of getting off the throttle earlier and braking later, and keeping a higher speed through the corner and applying less throttle on exit.

This is a reallying interesting post. You seem to have a good insight into LH's driving technique... I'd be very interested to know your view as to why LH has been out-qualified this year yet he is clearly the quicker driver of the two on race day?

Back to topic though, I seem to remember that there wasn't that much difference, if any, in fuel use between LH and NR at Abu Dhabi on Sunday up to lap 25 when NR had a problem... usually by lap 25 LH would have pulled a margin over NR by then...

[JimClarkFan]

The difference between Rosberg and Hamilton is clear I think, Rosberg like to drive through a corner perhaps slower on entry but faster out, whereas Hamilton is happy to throw the car in and as such spends less time on the throttle when cornering

[PlatinumZealot]

I think Nico and Lewis are very similar in how they drive the car but for differences in what they do to drive it. Nico is just as aggressive as Lewis at turn in, he is even more aggressive on the throttle IMO.

After the final Hamilton confirmed that He and Nico pretty much like the same car but he and Alonso do not.

[SectorOne]

Closest thread i could find, thanks to Somerfield for retweeting this so i could see it.
https://twitter.com/CONNYloveF1/status/ ... 9676047360

[condor]

From what I understand, two traits of Hamilton's driving style are his ability to carry momentum through a corner, and his ability to manage a loose rear end (both mentioned in Mark Hughes' excellent Italian GP report).

More momentum through a corner means less fuel burned accelerating out. Loose rear end means more rear braking, more energy harvesting and greater support from ERS – which also means less fuel burned.

There are also some less 'direct' explanations. If you accept that Hamilton has a natural pace advantage, then that means he can afford to do more braking-and-coasting than Rosberg for the same overall laptime. But 'absolute pace' is one of those things that can never really be defined, so probably best to avoid those explanations.

Yes that's correct about more 'momentum' (or the more appropriate term - speed) through a corner and this is precisely due to his ability to manage rear instability. There are two particular traits of Hamilton. He barrels into a corner with high entry speed and uses a combination of a feathering release of the brakes and minute applications of throttle to alter the weight transfer so that he doesn't get too much understeer because of the high entry speed and uses his high sensitivity to feel and predict when the rear is about to let go before it does.

Let me explain. When entering into a corner, the relatively easy and textbook technique is the 'slow in, fast out'. That is, get all the braking done in a straight line, release the brakes progressively but quickly and smoothly at the last possible moment before turning in to get weight transferring from predominant front bias during the heavy braking phase back to even front/rear distribution ready for turn in. Turn in while gradually applying throttle to further get even front/rear weight distribution because the very act of turning in washes off speed i.e a deceleration where weight is transferring to the front. Apply greater amounts of throttle as the car begins to straighten up, maximising the grip available from the 'grip circle'. i.e the depiction of available lateral vs longitudinal grip e.g tyres loaded up to max lateral grip limit means no longitudinal grip (traction) available, while a car pointing in a straight line has max traction.

Hamilton generally doesn't do the above for his race laps. He gets off the throttle earlier but brakes later to keep average speed up. He then rolls off the brakes quickly but turns in with still a little bit of front weight bias i.e he hasn't completely settled the car into an even front/rear weight distribution. This is tricky because too much front weight bias will unsettle the rear and have wild oversteer on entry, while coming off the brakes too quickly will result in understeer. The trick is to come off the brakes at corner entry and initial phase of the corner to exactly counter act the weight transfer to the front caused by the natural deceleration of going through a corner. While the 'slow in, fast out' technique' settles the car before turn in and uses throttle to counteract the frontal weight transfer due to deceleration going through a corner, the 'too fast in' technique skips getting the car settled before entry and uses release of brakes rather than throttle application to counteract the weight transfer.

The negative is that it's a risky technique and easy to get wrong because the rear is being finely balanced, and because of this power can't be put down quite as early as the 'slow in, fast out' technique because the rear is unstable. This is however somewhat mitigated by the fact that the 'too fast in' technique means higher average corner speed and hence requires less throttle application to get the same corner exit speed. The fuel saving comes from the pre-entry phase of getting off the throttle earlier and braking later, and keeping a higher speed through the corner and applying less throttle on exit.

This is a reallying interesting post. You seem to have a good insight into LH's driving technique... I'd be very interested to know your view as to why LH has been out-qualified this year yet he is clearly the quicker driver of the two on race day?

Back to topic though, I seem to remember that there wasn't that much difference, if any, in fuel use between LH and NR at Abu Dhabi on Sunday up to lap 25 when NR had a problem... usually by lap 25 LH would have pulled a margin over NR by then...

The reason Lewis has been out qualified is also the same reason why he takes care of his tyres better in the race. The natural or 'raw' speed between the two is very close. They set their cars up similar, though most times not exactly the same. Their driving style is also similar, though not the same.

There is a main reason why Nico is generally quicker in qualifying and another secondary reason those times he out qualifies Lewis by a large margin, such as Abu Dhabi.

The main reason for those times Nico has been slightly quicker than Lewis in quail. This year Lewis has really focused on setting the car up for the race and protecting the rears. It's no surprise that the turbo + ERS engines this year provide high torque and very easy to overwhelm the rears. So while both drivers setup is similar, Lewis has tended to set the car up with slightly more understeer while Nico has gone for more neutral. The difference is very little, but enough for Nico to warm his tyres up better for one lap. Conversely this has affected Nico's race pace as he has to go slightly slower in the race to protect his rears. The times we've seen him try and keep pace with Lewis, his tyres have dropped away much quicker. The tyre usage between the two is no more dramatically demonstrated than those races where Nico was running in clean air while Lewis was running in his dirty air lap after lap yet still got more life and end-of-stint pace out of his tyres.

So why doesn't Nico simply set his car up with slightly more understeer and not neutral to compromise qualifying pace slightly but improve race pace. Because Nico, like a lot of other drivers including top ones such as Sebastian, Jenson and Kimi also suffer, is unable to adapt their driving style quite as well when the setup isn't exactly how they like it. That is, when the setup is perfect to their liking they can extract almost 100% pace out of the car. However when it isn't, then they may only get 95% pace out of it compared to say drivers like Lewis or Fernando who can get 97% out of a less than perfect setup.

The secondary reason for when Nico has been far quicker in quail than Lewis is to do with tyre warm up. Especially with the softs and even more so with the super softs, tyre warm up is critical to the tyre's ultimate grip. By having a slightly understeer setup, Lewis is not working the rears quite as hard. While Nico with the slightly more neutral setup gets the tyre better into its correct temperature window.

This is not as critical with the harder tyres simply because they have a wider working temperature range and their peak performance temperature is lower than the softer tyres. The softer tyres have a narrower working temperature range and the peak performance temperature is very high. This can seem illogical but it's not. Heat into the tyre is a function of energy put into it. The softer tyres offer more grip which is obvious. This in turns causes higher energy into the tyre due to higher loads everywhere - braking harder, cornering faster, applying throttle more aggressively. So while the rubber is softer and offers good initial grip, the overall available grip is immensely more once it reaches peak operating temperature. So much so that even a few deg C below that peak could mean significant reduction in grip.

So while Lewis has a slightly understeer setup and can adjust his driving style to generally work the tyres equally, sometimes he judges the setup for the quail conditions incorrectly and the tyre temps fall slightly towards the lower end of the optimal working temps. This is when you see a significant difference such as the four tenths between the two at Abu Dhabi.

None of this is taking anything away from Nico's raw speed and ability. In fact, if both were driving their ideal setups for qualifying and the regulations then allowed parc ferme changes for a race setup, and both got their setups correctly then there would be very, very little difference in qualifying and race pace between the two.

Finally, to answer your question as to why the fuel use advantage that Lewis enjoyed over Nico all season didn't manifest in Abu Dhabi? Who's to say it didn't? Could the 'same fuel use' have been an illusion because Lewis slightly underfuelled his car relative to Nico because he knew he uses fuel less, needed a better start from P2 and banked on a decent probability of a safety car at that track? In fact, could that also have been the reason that Felipe's Williams got so close over the course of the race. That the real reason that Lewis' Mercedes had to run much slower than what it was capable of, was not solely because of saving the engine etc, but rather they were fuel saving for much of the race. Remember the fuel usage values presented during the race assume starting on 100 kg of fuel. I apologise for the lengthy post!

[condor]

I think Nico and Lewis are very similar in how they drive the car but for differences in what they do to drive it. Nico is just as aggressive as Lewis at turn in, he is even more aggressive on the throttle IMO.

After the final Hamilton confirmed that He and Nico pretty much like the same car but he and Alonso do not.

Yes that's correct. It's amazing how much of an effect a slight difference makes though.

[mrluke]

The fuel usage is reported as Kg of fuel used rather than a % as it was in the first 1-2 races. So not sure how this is influenced by the "assume starting on 100kg"

Otherwise good posts, reflects comments I have seen from Hamilton and elsewhere.

Throughout the season the Merc and Williams have had noticeably the lowest fuel consumption with Hamilton having an advantage vs Nico. At Abu Dahbi both Mercs seemed to have consumption in line with if not slightly worse than the other cars around them. I found this to be interesting and havent yet come with a reason why this is the case. Perhaps they were both running slightly richer (or less lean if you will) to save the engines but then driving them harder to achieve the required laptime?

[PlatinumZealot]

A user on this forum reported that Nico was more rear brake biased than usual in AbuDahbi. I think he did this after Lewis Overtook him. Lewis normally runs the higher rear bias because he has a higher braking pressure at the front. Because of the rear bias, his KERS charges faster and he can also save more fuel. That was to his downfall in Canada though. Nico normally is more front biased on the brakes than Lewis but for Abudahbi I can see why he would set his brake bias rearward after chasing Lewis.