Hi, I’m Andrew Shovlin and I’m here to answer your questions
from the 70th Anniversary Grand Prix.
The difference between the pole times last week and this week was around eight tenths
of a second, but there’s a number of factors playing into that.
Predominantly, it’s the weather.
The wind was a bit stronger in the second week, but it was also in a more awkward direction
that was pushing the car around a bit more in the corners.
So, that was making it a bit harder for the drivers to get their laps together.
Also, the track was hotter, not by a lot, only by about three or four degrees and that
just meant you were overheating a bit more at the end of the lap and also the air was
a bit warmer.
That results in a bit less downforce but also with the tyres, there’s a bit less cooling
effect as the car goes through the air.
So, those three things together were the big reason for that reduction in pace.
We had discussed the possibility that Red Bull might choose to start on the Hard tyre.
We knew that that tyre was quick enough to get it through Qualifying 2, so it was possible
from that point of view.
And also, if they thought they were going to be behind us on the grid it would give
them the opportunity to do something different.
When we had those discussions though, we did decide that we still wanted to start both
of our cars on the Medium tyre.
Now, that’s the tyre with less life in it.
We thought that it would be a good tyre off the line, it would have good initial grip,
good initial pace.
But the issue is if you start on the Hard and there is an early Safety Car, you are
then drawn into running that Medium for a longer period during the race.
Now, as it happens, we didn’t have the pace really to compete with them, we were having
to drive slowly to look after the tyres and fundamentally that was how they won the race.
Regardless of start tyre, I think it would have been extremely difficult for us to win
with those problems that we had.
The track was actually a bit cooler on the Friday, so that was one of the reasons that
it was easier to avoid the blistering.
The session is a bit later on the Friday, it starts at 3 O’Clock whereas the race
starts at 2, and it also clouded over.
So that had dropped it by five or six degrees, which was one of the problems.
But also, in the race you are doing more consecutive laps and the temperatures build up.
Now, that’s because within the rubber, so there’s a few millimetres of rubber, the
tread on the tyre, and that tread is moving around with the forces as we are cornering
and as we are accelerating and braking.
And as it moves, it generates heat.
So right in the middle of that tread gets very hot indeed.
And blistering basically occurs when that exceeds what’s effectively the boiling point
of the rubber.
You start to get bubbles forming and if you keep applying more and more temperature, those
bubbles can get bigger and bigger.
Now, eventually they can break out into the surface of the tyre, so you can see that on
the cameras.
That will cause a loss of grip because you have lost rubber that is normally in contact
with the road, that bit is missing.
But also, the very hot rubber is more susceptible to wear, so you can start to get that wear
spreading and that also damages the aspect of the tyre.
So, the big issue for us on Sunday was just that our temperatures were clearly hotter
than others, we were having to slow down to control it and that was fundamentally where
the big loss of pace was.
There were a couple of reasons that fed into the decision to stop Valtteri at that point.
We had asked him how the tyres were doing, whether he could do a few more laps and he
said it was probably OK to do another three or so.
The levels of vibration were increasing and that’s because the blisters create an imbalance
in the tyre, so as it rotates, it starts to vibrate.
So, he was feeling that.
But also we had Leclerc, who at this point was going quite quick behind him, so Valtteri
was a few seconds behind Verstappen, Leclerc was further down the road but we were worried
that if Leclerc moved towards them, Valtteri would lose that pit stop window that he needed
to take that stop and he would end up dropping behind Leclerc.
So, that was the main reason.
Now, with hindsight, Leclerc drops off his pace a bit after that so it may have been
possible to eke it out by another lap or two, but it wouldn’t have been by many.
After that stop, it was quite clear to us that Verstappen was actually managing his
car, managing his tyres.
So, he wasn’t running flat-out, he was just focused on getting it to the finish.
He was in P1, he’d done everything that he needed to do.
In Valtteri’s situation, we didn’t really have the car pace to attack.
If we closed up to the car in front, you lose downforce, you start sliding around and the
tyre situation gets worse.
But, I mean, the fundamental answer is we weren’t really quick enough to put pressure
on a Red Bull that day.
We never seriously considered keeping Lewis on a one-stop to the finish.
It was just a question of when we were going to make that final stop.
We could already see some degradation, so his times were dropping.
That’s the main reason that we knew we couldn’t go to end of the race on that tyre.
And then the next question is when you are going to do the stop, you have got to make
it early enough that he can catch up to the cars in front and attack them.
Now, tyre choice wise, we decided to go to the Hard tyre.
Even that tyre blistered, in that short space of time.
So, it provided more resistance though to the blistering and actually the Hard was a
really good tyre.
It was fast and if you are attacking people, it would cope better with any sliding from
the reduced downforce.
So, while the Medium would have been a possibility, for us it was always going to be the Hard
that we took.
Last week’s problem with the front tyres is very different to the issue we had this
week with the rear tyres.
So, the problem on the front, well that was a deterioration of the casing from fatigue.
Every time the tyre turns, it is deflecting, and it is under an awful lot of load.
Vertical load, so it is having to bend the carcass to form that contact patch, and then
also a lot of lateral load and longitudinal load as you corner and brake.
And over the period of the race, that starts to deteriorate the casing.
Now, Pirelli have fixed that problem by just adding 2psi to the front tyre and this week
it seemed to be in a very good place.
The issue on the rear though, that’s one of temperature.
And we were getting the centre of the tyre very hot.
Now, the issue there is, when it gets hot, it starts sliding and it generates more heat,
the pressures go up and you end up with a bit of a vicious circle, where you are losing
grip and keeping it under control becomes harder and harder as you go through the stint.
So, we need to look this week at how we can improve that issue with the rear, try and
understand exactly what was happening because it is the first time we have seen it this
year, and just make sure that we have some tools in place to deal with it better when
we get to another hot race.
I think we’d be foolish to say that we are not going to see this problem again and we
are not going to see it in Spain.
So, we need to be looking at solutions and if we can make good progress this week, in
the next few days, try and understand exactly the nature of our problem and that’s why
were we so much worse than the others, then I’d like to think we can get on top of it
for Spain.
But there’s no doubt Spain is going to be tough, Spa after Spain, that’s another very
high-energy circuit where you can get blistering.
So, our focus in terms of performance is all about how can we get the tyres cooler, how
can we avoid this problem.
So, hopefully we won’t see it again, but I think Spain will be a good test of whether
we have made the progress that we need to.
Thank you very much for all your questions and we’ll be back next week
after the Spanish Grand Prix.