My Post-Qualifying Analysis is possibly the most in-depth and complicated of the regular posts – and some would argue the most important, considering that with the lack of overtaking in the race means that most positions are decided during qualifying… ;)
Anyway, that aside, here is a short explanation on how I make my calculations for clarity and better understanding:
This is relatively straightforward – I take a graph of the official times posted by the FIA and graph them as a series of points to see how far away from the pole time they are.
Q3 Fuel Loads
For those who are not aware, in Q3 all cars have to run the amount of fuel that they intend to race with when qualifying. After qualifying has been completed, all cars are weighed and the weights of the cars are published.
What normally happens is that once the fuel weights are published I make a calculation based on the fuel use figures from the F1 Yearbook to calculate how much fuel is in the car and how it affects the performance of the car on the Q3 lap time. This calculation is as follows:
F= Fuel weight
W= Weight of car after scrutineering
L= amount of fuel (in KG) required to do a lap of the circuit (from the F1 Yearbook).
From this if I divide the fuel weight by the amount of fuel required for one lap, I can predict how many laps there will be until the driver has to make a pit stop. This method appears to be common practice as a few people (including the BBC) have ended up with similar numbers to mine.
The reason why three laps are subtracted is because the minimum fuel required to start the race would be just enough for a car to do an out lap, a parade lap and then an in lap for more fuel. Finally please note that 605 is the minimum weight of an F1 cars as required in the 2009 regulations.
However, I wrote a post comparing the F1 Yearbook figures to the actual ones observed during the races, and according to the figures, the F1 Yearbook figures are overestimating the stint lengths by one lap on average. Why is this the case? Well, we have very different technical regulations for the 2008/2009 cars and it seems that even though the engines have been de-tuned by 1,000 RPM, the new aero regulations and slick tyres seem to have actually increased the fuel consumption!
One final thought – we are assuming that the fuel consumption on the lap to the grid and the parade lap is close to the yearbook figure, when in fact they would probably be using less fuel…
Anyway at the end of the season I’ll re-visit that post to see if the trend continues – but for the rest of the year I’ll continue to use the F1 Yearbook fuel figures to make sure my predictions are aligned with everyone else’s
Q3 Fuel Adjusted Times
From the F1 Yearbook we can use figures for each circuit that calculate the cost in fractions of a second for each kilo of fuel that the car carries.
Therefore from this information we can estimate a fuel-corrected lap time by calculating how much of a penalty each driver was carrying with their fuel weight and subtracting this from the lap time. This is done as follows:
C= Fuel-corrected lap time
T= Q3 Lap time
P= Penalty in fractions of a second for each kilo of fuel carried
F= Fuel Weight in Kilos
Using this information and the Fuel Loads previously calculated, we can compare directly how quick each lap time was if it were set using as little fuel as possible.
Putting it all together
So what does all this show? Well, we can figure out who was really quick in qualifying in a more honest and equal way when we know how much fuel they were carrying. It has been the tactic of certain teams (for example Renault with Fernando Alonso in the Hungarian Grand Prix) to run a car with a very light fuel load in order to get a glory pole with a car that simply was not quick enough.
Conversely, we can also see who was carrying a ‘fat’ car full of fuel to run a really long first stint in the race. We can also make a guess at what kind of strategy the drivers intend to run as we know how many laps of fuel they are carrying!
So hopefully you now understand how it all works and what it all means ;)
I am continually trying to figure out better ways of displaying the results, so if you have any ideas at all then please let me know and I’ll try to incorporate them in future!