The Valencia street circuit has a habit of throwing up dull races, and has only managed to produce one safety car period in its four races. Somehow, I’m quietly hopeful that there’ll be a bit more to talk about this year. Perhaps an eighth winner, or a big result for Force India, or perhaps a point for Caterham. Each of these would need some circumstances to fall in their favour (unless Lotus are seriously quick – and the Friday evidence suggests they are fast, but not Bahrain fast) – and the safety car could easily provide the opportunity.
Lest we forget, the gap between the ultimate pole time and 20th place on the grid is less than 2.5s, with Petrov being within 1.5s of the fastest time in Q1. The field could be quite close, and even with the ‘delta’ rules providing a more benign impact of the safety car, the possibility of a big shake up, and a fascinating race, is there.
It is, of course, easier to consider the strategy without worrying about the safety car. The basic running on Friday suggests that the soft tyre is good for at least 15 laps, and the medium will be good for 25 or more. The degradation appears to be low (smaller than the fuel burn off) and the laptimes gradually get quicker in a stint. The basic picture is shown below, on the assumption that the medium tyres are about 0.4s off the softs (so new mediums are pretty close to used softs in pace) and the softs do 15 laps.
So two stops is optimal, and track position is gained by using two sets of the soft tyres. I think that a car needing three stops will suffer. It will be interesting to see which cars (if any) are brave enough to go for the softs at the first stop. This would be a sign of confidence in their tyre degradation – and to be honest, I only see the Lotus cars trying it.
One-stopping is possible if the soft tyre lasts longer – but I think that the cars will need to get to lap 20 (at least) to make it work. But then I would have said that Grosjean couldn’t have done what he did in Canada…
So what happens if we add a safety car? I’ve modelled this by matching up the curves (and guessing how far back in the queue you’ll be) at the point where the safety car comes out to see where it is better to stop. The most interesting case is that it does not take many laps for it to be worth stopping under a safety car and be able to maintain a two stop strategy – I reckon you’re better off stopping after only 5 laps (ignoring traffic effects) if the team is confident that only one more stop is needed. If we do get an opening lap safety car, then I expect that someone will think they can do the rest of the race on two sets of mediums.
Other than that, the question becomes whether the stop under the safety car replaces a stop in race conditions. Interestingly, the effect of new tyres and a small loss of time in the stop compensates for the extra stop. But only if there is no major time loss in traffic – which would be highly likely in such a close field – and a major risk. The advantage here is to be able to go long – and it pays dividends in two ways. Firstly, the longer you can stay out, the more likely you are to be able to stop under the safety car, as you don’t lose the opportunity by already having stopped. Secondly, if you can go longer after the stop, then you increase your chances of replacing a stop ‘under green’ with the stop under the safety car. Either way, running a second stint on the medium tyres improves this flexibility over running the soft tyres.
So I would expect that the majority will run two stops, and switch to the medium tyre at the first stop, as this provides a good combination of pace and flexibility. And as the strategies are likely to be similar for most, it could take a safety car to shake it up. And then timing is everything…