Pirelli has explained how it expects a new system to allow teams more tyre choice freedom in 2016 will work – as teams close in on finalising the regulations.
F1's tyre supplier is eager to deliver more variability to the races next year, and the concept of offering teams more scope to pick tyres that better suits their cars first emerged in the middle of this year.
Since then, discussions have taken place with teams and the FIA to try to finalise new rules which will be incorporated in a revised Article 24 of the Sporting Regulations.
Further progress was made in a meeting at the Mexican Grand Prix between Pirelli and team managers.
Rather than giving teams total free reign, Pirelli's current idea is to select three compounds for each grand prix for next year – and teams are likely to then be left free to select how many of each type of tyre they want.
It means teams could choose to be more aggressive by selecting the softer tyres, or adopt a split strategy of choosing the very softest tyres and the hardest one.
Teams could also choose different tyre sets for different drivers depending on what suits them best.
Pirelli racing manager Mario Isola said: “The idea is that we define the three compounds and then they can choose from that their 13 sets. It is not complete freedom, but we need to avoid free choices.
“They can choose three different compounds if they want, but they are obliged to run more than one in the race.”
One complication that has emerged with giving teams the option to pick tyres is the long lead time it may take for Pirelli to prepare them.
Motorsport.com has learned that a time frame of 14 weeks for flyway races and eight weeks for European events has been suggested, but this could be made shorter.
In theory, that means teams could have to pick tyres for the opening races of 2016 before their new cars have tested for the first time.
When asked if that would be too complicated, Isola said: “As long as it is the same for everybody, I don't think so.
“It is a complication because they need to decide in advance, but it is clear we cannot produce the tyre when we arrive on track.
“We can agree with them deadlines for each race to have the time, deliver the tyres and I think it is a good change for the show, because it introduces some variability. In my opinion it is a good step.”