Under the skin of C21.

The Sauber-Petronas C21 is, according to the team, a completely new car, uniting the latest regulation changes regarding safety and the most recent experience gathered in the wind tunnel, from calculations, production and material technology.

The principal aim of the development programme - carried out under the auspices of technical director Willy Rampf and his team - has been to maintain the excellent consistency and performance of the C20, which took both Nick Heidfeld and Kimi Raikkonen to top ten championship finishes, while introducing obvious improvements to the 2002 machine.

Aerodynamics

Seamus Mullarkey, Sauber's head of aerodynamics, and his team of twelve spend approximately 40 weeks a year at the wind tunnel situated in Emmen, about one hour's drive from the team's Hinwil base.

The first wind tunnel tests for the C21 were carried out as early as June 2001. During the conception phase of the C21, the requirements of the Petronas 02A engine, regarding cooling and space, were integrated into the programme.

The development aim for the C21 - to increase aerodynamic efficiency (the ratio of downforce and drag) while increasing engine cooling compared to the C20 - was achieved successfully by our aerodynamicists. At the moment, the aerodynamics department is focusing on further in-creasing the C21's efficiency and on working out different aerodynamic set-ups for specific track requirements with regard to the first races overseas. During the season, wind tunnel testing continues with unchanged intensity; new insights are applied for the further development of the car.

Weight

In principle, a constructor aims at making the lightest possible car, so that as much ballast as possible can be distributed usefully, up to the required 600kg of minimal weight set by regulations (including driveable car including driver and an empty fuel tank). With the C21, the Sauber team managed with much detail work and new construction principles to reduce the car's weight by another 10kg, so that more ballast can be placed in order to improve the car's driveability. Ballast is also an efficient means of lowering the car's centre of gravity.

Reliability

"You can only score points if you finish the race," reminds technical director Willy Rampf.

That is why, during the conception phase of the C21, the team made sure to take over reliable systems and develop them further, as well as using new developments on C20 test drives so as to discover their weaknesses early.

With a total of 80 per cent of newly constructed parts in the C21, it is clear that this is a very challenging task for construction, planning and manufacturing, and will reveal how well the team works behind the scenes.

The new engine in the is more powerful, lighter and smaller than its predecessor. Sauber continues its co-operation with both Petronas and Ferrari, which started five years ago and has been very successful. Throughout the season, about 40 engines will be built for Sauber in Maranello, but badged as Petronas V10s courtesy of the team's Malaysian backer and fuel supplier..

The Petronas 02A is based on the extremely reliable Ferrari engine, developed to the stage the Scuderia enjoyed mid-September 2001, which made Michael Schumacher and Rubens Barrichello so successful last season.

As Osamu Goto, head of the Team Sauber Petronas engine department, said: "The Petronas 02A is highly competitive. It will be very good."