Was 0.3 L of fuel + KERS enough to make it back to the pits?

[PlatinumZealot]

Does anybody know exactly where on the Barcelona track Hamilton stopped?

Is the gradients at the different parts of the track known?

I think we can calculate if he would have been able to make it back to the pits and in what time.

[Lurk]

He stopped in the climb just after turn 8. Their is also a climb turn 10 to 12.
He'd never have gone back to pit with still 1l of fuel at the end.

[Mr.G]

This is too geek for me

[Neno]

Hamilton stopped right after 8th corner.

[GrizzleBoy]

Gary anderson explains exactly what happened with the fuel:

http://www.bbc.co.uk/sport/0/formula1/18047760

"
The fuel rig guy put the rig on, but he had the handle set to drain fuel.

He discovered his mistake and switched it to put fuel in the car. But as a result he didn't put as much fuel in it as he should have.

You have to be able to drive back to the pit-lane and have one litre of fuel left for the FIA to test.

He went across the start-finish line 20 seconds before the chequered flag but if they had sat in the garage for three or four more seconds to get more fuel in, they still would have had time to cross the line and complete another flying lap. Sometimes I don't think McLaren think on their feet."

McLaren, in a nutshell.

[PlatinumZealot]

Track length 4,655 m
2.2kg per lap.




Lets do a very basic calculation.

I measuring up the image from just outside turn 8 to the Mclaren pits is approximately 2020. Or 2.02km.

I will find which segments of the track on the way to the pits are uphill and downhill.

[PlatinumZealot]

Ok.
Turn 8 to 9 is uphill. 0.219km
Turn 9 to 11 is downhill. 0.616km
Turn 11 to 13 us uphill. 0.374km
Turn 13 to the pits is downhill. 0.75km

Assuming 7th gear to save fuel - F1 idle speed is 4000 rpms. The car should be light enough to drive in 7th gear at 5000rpm. This is about 5000/18000 * 320km/r = a speed of 88.9km/r.

Let us assume that the fuel injected is proportional because these untra high rpm engines with their over 100% VE tend to have a fairly flat torque curve.

So a very basic assumption here... average lap speed = 4.655km/90 seconds per lap/*3600hr = 186.2 km/hr.

I am assuming the the Williams figure of 2.2 kg/lap is taken over a whole race. The average lap time of the leader in 2011 was 90 seconds.

That speed is an average lap rpm of 10,473 rpm. So this is your 2.2 kg/4.655km of fuel at that rpm.

Now going at 5000rpm will consume 5000rpm/10473rpm* 2.2kg/4.655km = 0.226kg per km run with petrol only*

[PlatinumZealot]

This is all assuming the G7 fuel setting which is the highest power fuel setting so we can trim these down later. Remember in 2011 the front runners were going full power all the way.

Now for the two up hill segents.. he will consume about 0.593km*0.226kg/km = 0.134kg of fuel

Anybody know the density of Mobil1 F1 fuel?

He can coast downhill in neutral at 4000rpm, even turning his engine off for the last 0.75km from turn 13 into the pits.

We have not even considered KERS yet. So, so far it is looking good that Hamilton could possibly have made it into the pits with only 0.134kg of fuel los without using KERS and his engine at 5000 rpm going at a speed of 89 km/hr. It would have taken him about 1 mintue and 20 seconds to reach the pits from after turn 8.

Anybody up for the KERS calculations?

[GrizzleBoy]

My brain already exploded, but interesting nonetheless.

[Goran2812]

n_smikle ... nice

[TheRMVR]

This is all assuming the G7 fuel setting which is the highest power fuel setting so we can trim these down later. Remember in 2011 the front runners were going full power all the way.

Now for the two up hill segents.. he will consume about 0.593km*0.226kg/km = 0.134kg of fuel

Anybody know the density of Mobil1 F1 fuel?

He can coast downhill in neutral at 4000rpm, even turning his engine off for the last 0.75km from turn 13 into the pits.

We have not even considered KERS yet. So, so far it is looking good that Hamilton could possibly have made it into the pits with only 0.134kg of fuel los without using KERS and his engine at 5000 rpm going at a speed of 89 km/hr. It would have taken him about 1 mintue and 20 seconds to reach the pits from after turn 8.

Anybody up for the KERS calculations?

And this can only happen when Hamilton at turn 8 would understand the exact gravity of the issue and act instantly. I think by the time Whitmarsh would've explained him on the radio he would already be at turn 12 cruising at normal inlap speed. McLaren screwed up, nothing more..

[GrizzleBoy]

This is all assuming the G7 fuel setting which is the highest power fuel setting so we can trim these down later. Remember in 2011 the front runners were going full power all the way.

Now for the two up hill segents.. he will consume about 0.593km*0.226kg/km = 0.134kg of fuel

Anybody know the density of Mobil1 F1 fuel?

He can coast downhill in neutral at 4000rpm, even turning his engine off for the last 0.75km from turn 13 into the pits.

We have not even considered KERS yet. So, so far it is looking good that Hamilton could possibly have made it into the pits with only 0.134kg of fuel los without using KERS and his engine at 5000 rpm going at a speed of 89 km/hr. It would have taken him about 1 mintue and 20 seconds to reach the pits from after turn 8.

Anybody up for the KERS calculations?

And this can only happen when Hamilton at turn 8 would understand the exact gravity of the issue and act instantly. I think by the time Whitmarsh would've explained him on the radio he would already be at turn 12 cruising at normal inlap speed. McLaren screwed up, nothing more..

I think the point is that if McLaren had any competance about them, they would have told him from the moment he crossed the line after qualifying. They can monitor fuel amounts and consumption from the pit wall.

Either way, it's good to know the possibilities that n smikle is brining to light.

[zyphro]

I'd bother attempting it, but it's 1.22am!!!

[Lurk]

@n_smikle: F1 fuel density should be between 0.720 and 0.775 kg/l at 15°C 2 or 3 years ago. The accepted number for "fast" calculation is 0.75 (at least they use this number on french TV and when Briatore was giving strategies of their opponents 5min before the race: it was fun)

I really thought he never could have make it but maybe I was wrong, even if the calculations have some inaccuracy (F1 aren't running in 7th all the lap so higher average rpm, higher consumption in uphill).
But 0.226kg/km is still more or less 30l/100km which is 2/5th of f1 consumption on "normal" race mode so it is plausible and could be lower (I'd ask about that). He could have run engine turned-on at least 1km and without using Kers...

Concerning KERS calculation if we assume a fully charge KERS, it is equivalent to 80HP during 6s.
Given that my late '89, 55HP Ford Fiesta was able to cruise at 90km/h without efforts, I think that his KERS could have helped him onto uphills to save a little more fuel. I must say that my calculations could have some inaccuracy too. But please be indulgent, it's 3:00AM...

[Ganxxta]

Nice calculation.
Also I read somewhere that they can turn off 4 Cylinders in fuel save mode, so if McLaren would have some good engineers, they would have told Hamilton directly after the finish line to go to fuelsave mode, use Kers uphill, hell even turn the speedlimiter on (80kmh) if Hamilton can't drive slowly