An FIA investigation into Mercedes' starting tyre pressures made for an extraordinary end to the day at Monza, with the result uncertain for some time after the chequered flag fell. Was there any trickery - and were the Silver Arrows lucky to avoid punishment? Not according to the stewards, nor indeed Mercedes-Benz' head of motorsport, Toto Wolff, who says the entire issue centred around procedural uncertainty rather than anything underhand...
Q: Toto, when did you realise that you had a problem with the tyre pressures on both cars – how did that information come to you and how did you react?
Toto Wolff: I think it was about ten or 15 minutes before the end [of the race] when we got the information from the stewards that the tyre pressures measured on our cars were being investigated. No more information.
Q: Can you explain what happened before the race with the tyre blankets? Were they heating properly?
TW: We followed the procedure which was established with Pirelli: have the tyres in the blanket and check the pressures with Pirelli. So there is always a Pirelli guy with us, and the pressure was well above the minimum - because safety is important for us! We put those tyres on the car and for whatever reason - maybe one of the tyres cooled down - a different pressure was found on one of the tyres. A very tiny discrepancy! I have no idea what happened then - whether it was not working or if it was detached. The question is all about the procedure: when do you measure?
Q: When do you usually check the tyres? When you leave the pits? Before the start? On the grid? When?
TW: You check the tyre pressure when you put the tyres on the car. This is the procedure right now. But probably the ‘when’ needs to be defined in the future!
Q: Why was there such a discrepancy between Lewis’s [Hamilton] car and Nico’s [Rosberg] car? And why did you instruct Lewis to push hard towards the end of the race?
TW: To be honest we don’t know why we had such a discrepancy. And in the end it can be very performance costly if you have one tyre that has a different pressure than the others. And why did we tell Lewis to push? That was when we got the information that there was an investigation into tyre pressures. We didn’t understand what was going on, but we thought that there could be possible penalties and in order to gain a little bit of a margin we asked him to push.
To be honest we don’t know why we had such a discrepancy (with pressures). In the end it can be very performance costly if you have one tyre that has a different pressure than the others.
Toto Wolff
Q: Why would you willingly disconnect a blanket too soon in the first place and is there a need to redefine the tyre procedures before a race?
TW: If you didn’t disconnect the tyres from the generator you would need four generators behind every single tyre, so you would have cables all over [the place]. So the normal procedure - and I think all the teams handle it in this way - is that you keep the tyres warm, you disconnect them and put them on the car. So I think it is about the procedure of measuring. When do you measure?
Q: But when five minutes before the race the FIA finds a tyre on Lewis’s car where the pressure is incorrect, then you still have enough time to correct that. Why didn’t you do that?
TW: Because we didn’t get the information - simple as that!
Q: When you spoke to the stewards after the race was there ever a stage where you imagined that they might exclude you from the race? Or did your arguments immediately win them over?
TW: We told them which procedures we followed - and that this procedure seemed the most logical and safest - and I think this is what they followed.
Q: Who met with the stewards? You and who else?
TW: I wasn’t at the stewards. It was Paddy (Lowe) and two of his senior engineers.
Q: Did you disconnect the tyre blanket as you normally do?
TW: Yes.
Q: Cynical people might think that you deliberately set the tyre pressures so they were high enough to reach the minimum requirements but would then drop below that once the tyres cooled down, and in that way you’d gain an advantage…
TW: But then why would you do that only on one tyre. After Spa we have been working very intensely with Pirelli to make these tyres safe - and now we should do something so ridiculous? And why only on one car? That is not cynical - this is bulls**t!
Q: How risky was it to put an engine in Nico’s car that had already done five races?
TW: Yes the engine was on its sixth race, so it was on high mileage, but in the end it was not the engine that failed but a leak in the cooling system that caused Nico’s retirement.
Q: Was there any warning before he had to park his car?
TW: No, we didn’t get any warning. We gave it a little push towards the end in an effort to catch Sebastian (Vettel) and then came the end of it.