The 2009 FIA Formula One World Championship season will see some of the biggest changes ever made to the sport and Bridgestone are right at the very heart of this with the reintroduction of slick tyres, which have been absent for the past eleven years.
A slick tyre – where there is no pattern on the tyre tread surface – is the fastest type of dry weather racing tyre, however slicks have not been part of Formula One since the start of 1998, after the sport’s regulators introduced grooves in order to slow cornering speeds.
The return of slicks in 2009 has not been made to allow cars to go faster, however. Instead, the change has been made as part of a large number of revisions, brought about with the objective of making racing more exciting by giving a greater opportunity for overtaking to occur.
If a 2009 Formula One car lined up alongside its brother from the 2008 season, it’s easy to see the differences. The 2009 bodywork regulations are designed to mean less downforce for the cars, so there are fewer winglets and more restrictions to what teams can do aerodynamically to their chassis. The front and rear wings have been changed radically, with the front wing now far lower and wider than before, and the rear wing taller but narrower.
The changes are more than skin deep, with Kinetic Energy Recovery Systems (KERS) allowed within the regulations. These systems store energy which is generated during braking and allow the redeployment of up to 60kW (around 80hp or the same power as an entry-level Volkswagen Golf) of this energy in bursts of up to 6.5 seconds over a lap.
But for Bridgestone, the most significant change is the return of slicks.
“Slicks are a big change for Formula One, and it brings the sport back in line with most circuit racing formulae we see around the world,” says Bridgestone Director of Motorsport Tyre Development, Hirohide Hamashima. “A slick has a bigger contact patch than a grooved tyre of the same size and requires a softer tyre compound, so it gives more grip.”
Whilst the tyres give more mechanical grip, the cut in downforce means that the grip provided by the cars being pushed down into the road from their wings is significantly reduced which should mean an overall increase in lap time.
“The new cars, combined with our new tyres, mean that many variables have changed,” says Hamashima, “and learning how to gain the best advantage from these variables will be the challenge of the season.
“The front tyre now has a bigger contact patch relative to the rear tyres. This is because the grooved area on the front tyre took up a larger proportion of the tread area than on the rear tyre, so the removal of the grooves changes the balance.
“On top of this there is the aerodynamics change with a lower and wider front wing, combined with a taller and narrower rear wing, which also moves the balance in the direction of more aerodynamic grip at the front, and less at the rear.”
