2009 electoral calendar

Formula One tyres play a significant role in the performance a Formula One car. The tyres have undergone significant changes throughout the history of Formula One, with different manufacturers and specifications used in the sport.

Formula One tyres bear only a superficial resemblance to a normal road tyre. Whereas the latter has a useful life of up to 80,000 km, the tyres used in Formula One are built to last less than one race distance. This is determined by the compound of the rubber used. In 2005, tyre changes were disallowed in Formula One, the compound was harder as the tyres has to last the full race distance (around 300 km). Tyre changes were re-instated in 2006, following the dramatic and highly political 2005 United States Grand Prix (see below).

By regulation, the tyres feature a minimum of four grooves in them, with the intention of slowing the cars down (a slick tyre, with no indentations, is best in dry conditions). They can be no wider than 355 mm and 380 mm at the front and rear respectively. Slick tyres are to be reintroduced as of 2009 (which has been confirmed by the FIA in addition to the fact that many teams have been testing the 2009 specification rubber in testing) but the FIA regulations (though they can be changed) still have F1 using "grooved" tyres in 2008.

For the 2007 season Bridgestone became the sole tyre supplier in Formula One with the withdrawal of Michelin, and introduced four compounds of tyre, two of which are made available at each race. The harder tyre is more durable but gives less grip, and the softer tyre gives more grip but is less durable. Both compounds have to be used by each car during a race and the softer tyre has a painted white stripe in the second groove to distinguish between compounds. This was introduced after the first race of the season when confusion occurred because a small dot was put on the sidewall of the tyre, instead of the white stripe. Each team must use each specification during the race, unless wet or intermediate tyres are used during the race, in which case this rule no longer applies.

In extremely wet weather, such as that seen in the 2007 European Grand Prix, the F1 cars are unable to keep up with the Safety Car in deep standing water due to the risk of aquaplaning.

Both front and rear tyres are typically 660 mm in diameter.

2005 United States Grand Prix controversy

Main article: 2005 United States Grand Prix

The 2005 United States Grand Prix was plagued by Tyre issues. This caused the race to be run with only six competitors

On Friday, 17 June 2005, during the afternoon's practice session, Ralf Schumacher driving for Toyota, crashed heavily in Turn 13 of the Indianapolis Motor Speedway road course, apparently as a result of a left-rear tyre failure. Turn 13 on the Indianapolis Motor Speedway road course is a high speed banked turn, unique to Formula One racing, that causes a greater than usual lateral (horizontal) load. This pressure can cause the side walls of the tyre to bow and wear in abnormal places. The following day, Michelin reported that the tyres it had provided for its seven customer teams — BAR, McLaren, Red Bull, Renault, Toyota, Sauber, and Williams — were unsafe for extended high-speed use on this turn, and announced its intention to fly in another set of tyres from its Clermont-Ferrand headquarters. However, the replacement tyres flown in, which were of the type used in the Spanish Grand Prix earlier that year, turned out to have the same problem when tested.

In a letter to FIA Race Director Charlie Whiting Michelin representatives Pierre Dupasquier and Nick Shorrock revealed that they did not know the cause of Schumacher's tyre failure, and unless the cars could be slowed down in Turn 13, Michelin's tyres would be unsafe and unsuitable for use during the race. Whiting replied, expressing his surprise that Michelin had not brought along a second set of tyres, suggesting that the teams be informed of the maximum safe speed in Turn 13, and offered to monitor the turn by penalising any excess speed on the Michelin cars. He also addressed several solutions which had been proposed by the teams, insisting that use of the tyres flown in overnight would result in penalties, and the placement of a chicane in the turn was "out of the question" — the race would not be sanctioned by the FIA (making it a non-championship race) if the track layout was changed. He deemed the Michelin teams' proposals to be "grossly unfair" to the Bridgestone teams. In a second letter Dupasquier and Shorrock announced that they would not permit their teams to race on Michelin's tyres. The race then took place with only the Bridgestone teams taking part.

"Make Cars Green" campaign

Bridgestone used tyres with green grooves for the 2008 Japanese Grand Prix. Rubens Barrichello (top) demonstrates the "prime" compound, whilst Nick Heidfeld (bottom) is running on the "option" compound, distinguished by the fact that one of the grooves is white.

At the 2008 Japanese Grand Prix the tyres had the grooves painted green, as part of a promotion by the FIA to reduce the impact of motoring on the enviroment, called Make Cars Green. The softer of the two types of tyre still had the innermost groove painted white, as per normal.

Manufacturers

Since the start of the 2007 Formula One season Bridgestone have been the sole manufacturer. Past manufacturers include:

• Avon
• Continental
• Dunlop
• Englebert
• Firestone
• Goodyear
• Michelin
• Pirelli

Records

Ordered by number of races won.

Pos	Manufacturer	Seasons	Starts	Wins	Sole supplier	First win	Last win	World Championships
								Drivers	Constr.
1	Goodyear	1959 – 1998	494	368	113	1965 Mexican Grand Prix	1998 Italian Grand Prix	24	26
2	Bridgestone	1976, 1977 1997 – 2008	206	137	78	1998 Australian Grand Prix	2008 Japanese Grand Prix	8	8
3	Michelin	1977 – 1984 2001 – 2006	215	102	0	1978 Brazilian Grand Prix	2006 Japanese Grand Prix	6	4
4	Dunlop	1950 – 1970 1976,1977	175	83	0	1958 Monaco Grand Prix	1970 Belgian Grand Prix	8	9
5	Firestone	1950 – 1975	121	49	11	1950 Indianapolis 500	1972 Italian Grand Prix	4	3
6	Pirelli	1950 – 1958 1981 – 1986 1989 – 1991	200	44	0	1950 British Grand Prix	1991 Canadian Grand Prix	6	0
7	Continental	1954 – 1958	13	10	0	1954 French Grand Prix	1958 Argentine Grand Prix	2	0
8	Englebert	1950 – 1958	61	8	0	1955 Monaco Grand Prix	1958 British Grand Prix	2	0
9	Avon	1954 – 1958 1981 – 1982	29	0	0	N/A	N/A	0	0

External links

• FIA tyre regulation summary
• FIA tyre regulations
• The Aerodynamic Development of the Formula One Car
• Bridgestone Teams, Single Tyre Formula And Sole Supplier
• The ATLAS Rough Guide: How to Set Up a Formula One Car (Part One)
• MSN Formula One: Tyres