18" wheels are in for 2021, but tyre blankets are out!

The FIA has launched a tender process for Formula 1's next tyre supply contract that will run from 2020 to 2023, with 18-inch wheels introduced from 2021.

The governing body has also indicated that tyre blankets should be banned from 2021 when the new wheel size comes into effect.

The tender process, which will remain open until the end of August, will centralize parties meeting the FIA's technical and safety requirements before commercial rights holder Liberty Media conducts negotiations with the bidders and proposes its final selection to the FIA.

Pirelli has been Formula 1's single supplier since 2011 and indicated earlier this year its potential interest in taking part in the tender process.

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Oddly, because of the future contract's initiation in 2020, when cars will run on current 13-inch wheels, F1's future supplier will be forced to develop specific tyres for that season before developing a different spec of rubber thereafter.

The prospect of banning tyre blankets has been a controversial subject among F1 teams, with safety issues at the forefront of everyone's concerns.

The FIA has sought to alleviate those worries however.

"Tyres should provide safe performance when leaving the pits cold," stated the FIA's official tender document published on Thursday.

"The glass transition temperature must be chosen so that the tyres are never in a ‘glassy state’ when either the ambient or the track temperature is above 10 degrees centigrade."

The future provision will also take into account winter testing conditions.

“For winter testing a specific low temperature tyre will be required. This will form the bulk of supply to the teams for European winter testing with a limited number of race compounds available.

"Wet and intermediate tyres should also be capable of running without the need for pre-heating."

In its release, the FIA also underlines the "overriding objectives" for tyres which are the "improvement of the show, driveability characteristics, absolute performance and operating conditions".

The governing body also requests that three compounds - Hard, Medium and Soft - are available at each weekend to "create the maximum number of race strategies yielding race times such that multi-stop strategies provide just enough potential of a beneficial outcome to encourage the greatest variety in racing spectacle."

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