Q&A with Bridgestone on recent Jerez tests

They may be back on track for some much needed dry running at a sunny Barcelona circuit on Thursday morning, but Formula One racing’s official tire supplier, Bridgestone, are still contemplating the wet weather they faced at Jerez last week. Here the team’s assistant technical manager Jun Matsuzaki reflects on what they learnt at the sodden test…

Q: How much of a factor was the weather in Jerez?
Jun Matsuzaki: I think this is the most rain ever seen at Jerez, and on Thursday night it was almost impossible to leave the circuit as there was so much water on the roads. Fortunately, there was no more rain left in the sky so we had good dry running on Friday and Saturday which was very valuable.

Q: What are the difficulties with testing in wet conditions?
JM: The difficulty with wet conditions is that they are never constant so there are too many variables to gain good data and develop cars. If it is raining, the circuit is getting wetter so lap times become slower because of this. If it is a drying track, there will be improving lap times due to the improved track surface, a change to the car, or use of a different tire. This makes it very difficult for everyone. Also, logistically, we had to bring out extra wet and intermediate tires to enable the teams to continue running in these difficult conditions.

Q: How have the wet and intermediate tires worked in Jerez?
JM: The difficult factor has been that these tires have been used before the teams have been able to get good dry set-ups on their cars. This is important to have as it makes finding a wet set-up far easier. This has meant we've seen a variety of wear characteristics, particularly on the intermediate tire which is used on a drier track than the wet. When the intermediate is used on a track which has dry patches, or on a car where the set-up is not so balanced, you do see more wear with this tire. The additional weight of the fuel loads in this season's cars also adds to the difference in wear from that seen before. Equally, Jerez is a circuit which has quite high wear so we expect better performance as teams develop better set-ups of their cars and at less severe circuits than Jerez.

Q: What have you learnt about the dry tires?
JM: Saturday was the only day where we started with a dry track and we had very little rain through the day, so we are still working with limited data. We can say that warm-up has been good for all three dry compounds here, with a definite improvement from last season's tires. It is too early to understand the differences between the compounds. Jerez is particularly severe on the rear tires and we are happy with their performance from what we have seen so far. Hopefully, we will have better weather in Barcelona.