For while Pirelli only went as far as talking about generic ‘running conditions’ triggering the blowouts for Red Bull and Aston Martin, the swift move from the FIA to impose a raft of new measures is a clear indication of the areas it suspects teams could be operating in.
In the lengthy updated FIA Technical Directive that was issued to teams on Tuesday, in response to what happened in Baku, it is obvious that tyre pressures are at the centre of this most recent storm.
Sure there are no suggestions Red Bull nor Aston Martin had been doing anything illegal, but the manner of what is changing from this weekend’s French Grand Prix offers us clues about what may have been going on.
Red Bull may have been correct in stating that it has followed the rules and Pirelli’s guidance to the letter, but part of the problem is way that the current situation those parameters are judged left some grey areas.
With the only requirement being for a limit on tyre temperatures in the blankets, and starting pressures when tyres are still fitted, that still left room for teams to do things once those checks had taken place.
If a team could drop pressures below the recommendation by the time the car left the pits, and then managed to find a way of them not rising too much out on track as the tyres warmed up, it could fully comply with the rules and yet not be at a pressure level where Pirelli would normally expect them to be.
So in looking at what the FIA is bringing in for the French GP, and new limits for teams, we can perhaps get some clues about what tricks may have been used for performance gains.
And irrespective of what teams may or may not be doing, the new cold pressure checks on tyres after they have been removed from cars should clampdown on anyone trying to get around the system by running lower than Pirelli intended.
Here then we look at four theories on what teams could have been doing that will no longer be allowed.
Pirelli tyres allocated to Red Bull are sorted into blankets in the paddock
Photo by: Simon Galloway / Motorsport Images
Removing the blankets early
The most obvious way for teams to play around with tyre pressures is with temperature – for if the air in the tyre is heated up, then it will expand to increase the pressure to pass the pre-running checks.
Then, if it is left to cool, the air will contract and the tyre pressure drop down to a level that is better for car performance.
Many years ago, the FIA moved to stop teams doing this through dramatically heating up their tyres, which is why there is now a limit on how hot the tyres can be heated in the blankets.
However, that has not stopped some teams still trying to take things to the limit in terms of heating the tyres – and then cooling them as much as they can prior to the cars running.
One way to do this would be to remove tyre blankets from cars in the garage well before they intend to go out on track.
This is something that Lewis Hamilton highlighted in Monaco when he told Sky F1 that Red Bull had done this in Spain.
“If you look at the last race (in Spain), for example, we were supposed to all keep our (tyre) blankets on in qualifying,” he said.
“Red Bull were allowed to take theirs off, and no-one else is allowed to. So I think we just need to make sure it’s consistent for everyone.”
From the French GP, such activity will no longer be permitted with teams told that the removal of blankets prior to the cars getting ready to leave the garage will be interpreted as them trying to cool tyres.
The FIA TD states: “The removal of any blankets when the tyres are not yet fitted on the car, their untimely removal with the tyres fitted on the car, or delaying the release of a car from the garage for no valid reason with the tyre blankets removed will be considered as a way to cool the tyres.
“Teams will need to justify a valid reason for any delayed release of over 30 seconds, or frequent delayed release.”
Photo by: Mark Sutton / Motorsport Images
While teams have always had to use tyre pressure gauges calibrated by Pirelli and sealed by the FIA, that in theory has not stopped them making use of any leeway in the readings to push the tyre pressure margins.
Small variances can creep in to the system when checks are made, and previously teams knew that if there was any ‘small discrepancy’ with a set of tyres they would be allowed to inflate them – so there was nothing to lose by pushing the limits.
Now though the FIA is getting tougher and will not allow any additional tolerances that result in the tyres being outside the prescriptions.
“It is the teams’ responsibility to add any additional margin to operate tyres within the prescription limits,” it said.
Now any team found to be outside the limits will still be asked to inflate the tyres more, but cases of large and/or systematic discrepancies will be reported to the stewards.
A Haas team member at work, in a corridor of tyres stacked in heated blankets
Photo by: Andrew Hone / Motorsport Images
Overheating the blankets
The teams’ abilities to use temperatures to control the pressures means that tyre blankets are an obvious way of managing the situation.
The FIA TD also restricts teams using the blankets for too long – or playing innocent over a blanket control reading that gives a lower temperature than the tyre is at.
From France, teams will no longer be allowed to heat the tyres for a lengthy period of time. They can now only be heated when they are intended to be used in the following session.
Furthermore, teams will not be allowed to keep their tyre blankets running overnight and above temperature, so that when tyres are fitted in the morning they are already roasting away better than teams who have just switched theirs on.
The FIA says tyre blankets must now be physically disconnected except for a period allowed by Pirelli.
Further, they must ‘make sure temperature displays of all control boxes in use are switched on and easily visible.”
A Pirelli technician takes some data readings
Photo by: Andy Hone / Motorsport Images
Using special gases
Another way for tyre pressure to be changed is through the use of special gases or their moisture content as they are inflated.
This could potentially change the way that temperature affects the expansion of the air inside the tyre. Now, such behaviour will no longer be allowed.
The FIA noted said that: “Any modification to the inflation gas composition or moisture content aimed at reducing on-circuit pressures is not permitted.
“This includes increasing as well as reducing inflation gas moisture content, and the addition of any solid, liquid or gas not permitted for this use in the Technical Regulations.”
The FIA also reminded teams that they must follow Article 12.5.1 of the technical regulations at all times which states that: “any modification or treatment such as cutting, grooving, the application of solvents or softeners is prohibited.”