Australian Grand Prix: Some Interesting Numbers

Posted on March 20, 2012


Although it can be argued that there was some strategy variation in the Australian Grand Prix, realistically the gap between the soft and medium tyres was such that it didn’t really make all that much difference, and the only winner from strategy was likely to be Sergio Perez, until the safety car intervened. The rest of the race was about the pace of the cars, and racing, which is really as it should be.

So with little in the way of strategy variations to look at, and the driver-by-driver assessment to come, I thought I’d put down some of the interesting numbers from the last race, and make some comparisons with the 2011 event. You may have noticed that the pole time was a full second slower than last year with the ban on the blown diffusers and restricted engine maps, and that the fastest race lap was 0.6s slower as well. As it happens (and this is quite rare), the fastest race lap happens to be reasonably representative of the race pace, as the pace of the fastest car (fuel corrected to the early laps) in the 2012 race (Button) is 0.6s slower than the fastest car in the 2011 race (Vettel) on the softer option tyre. Pirelli promised that the gaps between the compounds would be smaller this year, and they seem to be true to their word so far – the prime tyre was 1-1.2s per lap slower than the option in the race last year, and this year it was 0.2-0.5s slower. Allowing for the fact that the prime was the medium tyre this year, and the hard tyre (so two steps difference in compound) last year, Pirelli seem to have got it right.

In 2011, the penalty for racing on used tyres (with one qualifying run on them) was about 0.3s – it so happens that doing two qualifying runs on them doubled this to 0.6s, but there is no reason to expect that this would be the case. In the few cases where I could pick that a car had different pace when on the same compound tyres (Massa and Di Resta), the penalty of 0.3s per lap for using tyres which have already been used in qualifying seems to fit the 2012 tyres as well. Note that the time differences in using different tyres compare new against new. Therefore a gap of 0.3s makes new primes the same pace as new options. This is bound to come into play this year – and was clearly relevant in Australia where new primes and used options were basically equal in performance. There is a caveat on this – Mercedes paid a big price on used soft tyres – it is impossible to say on the evidence to hand whether this is due to life taken out of the tyre in qualifying, or whether they have to be very careful in the race just to get the tyres to survive. We should learn more on Sunday.

The numbers for fuel effect at 0.08s per lap and for degradation at a little less than this (0.06s per lap fits quite well across the board) fit well with the data from last year, and seem to be OK for both types of tyre. Thus, the pace loss over stints may well be the same on all tyre types, but as last year, the number of laps this can be sustained differs from compound to compound. The good news is that this makes things simpler to analyse.

To support the assertions that the grid has closed up, and that the midfield are closer to the front on pace, the heart of the midfield was about 1.5s down on the pace-setting Vettel last year. By the end of the year, it was more like 2-2.5s depending on the circuit. This year, the gap to Button was more like 1s, so although this may well increase during the year, it does seem like the cars are closer together on performance than they were 12 months ago. The biggest gainers are Caterham (from over 4s off the pace to about 2.5s off the pace), followed by Williams (from 1.9s to 0.8s off the pace). Losers? Ferrari (from pretty much on the pace to about 1s off). Amazingly, Marussia appear to be exactly where they were. As do Sauber. Another surprise – Mercedes race pace was better in 2012 than in 2011 relative to the leader, so they have improved tyre troubles or not.

So the good news for the intelligentF1 analyses. We can still pick the difference between tyre compunds based on the data, and the difference between new and used sets. We can use last year’s data as a good starting point for fuel effect and for degradation modelling. And the expected pace of the cars is not far from last year, which can help us with an assessment of what fuel loads are being run on Fridays. Maybe this Friday there’ll be something useful to analyse…