Features - Technical

SEPTEMBER 1, 1994

The 1995 Technical Regulations

BY JOE SAWARD

There will be a radical change in F1 design next year, but most of the design parameters will not be changing. The 1995 rules demand that the underside of the car - which is currently flat - has to be 'stepped' so that on either side of the central section of the car, the bottom of the car must be raised by 2.5cm. This may not seem much but it will have a dramatic effect, removing as much as 50% of the downforce generated by the current flat bottom.


There will be a radical change in F1 design next year, but most of the design parameters will not be changing. The 1995 rules demand that the underside of the car - which is currently flat - has to be 'stepped' so that on either side of the central section of the car, the bottom of the car must be raised by 2.5cm. This may not seem much but it will have a dramatic effect, removing as much as 50% of the downforce generated by the current flat bottom.

The current arrangement uses the flat floor to create a low pressure area between the bottom of the car and the road, which has the effect of sucking the car to the road. But this only works if the floor is close to the road. By raising the floor on either side of the car, the FIA will reduce downforce from the flat bottom by as much as 50%, which translate into around 30% of the overall downforce of the car. A big reduction. And there will be further losses because the wings - front and rear - are also being reduced in size.

This will mean that engine power becomes increasingly important, because the greater the power available the greater speed achieved and the greater the downforce that can be generated.

But this will not necessarily bring about an entirely new era in F1 racing. It is a revolution in F1 thought, but it does not mean that the essential layout of the cars will change a great deal. The reality is that F1 designers are already very restricted as to the kind of cars they can design.

They must put the fuel tank between the driver and the engine, and this must not extend sideways more than 22.5cm from the centre-line of the car. It cannot be placed in the sidepods.

Moving the driver is also difficult because the driver's feet cannot be in front of the front axle line. In the past this has resulted in designers squeezing their drivers into too smaller a space, but the 1995 rules put paid to that by imposing a minimum distance of 75cm between the front of the cockpit opening and the front axle line. This means that 1995 cars will have to have longer monocoques.

Fuel cells will have no minimum size limitation in 1995 and designers are expected to reduce the tanks now that refuelling is allowed. Fuel tanks will probably be around 100-120 litres next year rather than this year's obligatory 200 litres. This will have the effect of making the cars much neater - and potentially shorter - at the rear.

Much will depend on research currently being done by teams to find the optimum size of a fuel tank in relation to the engine configuration.

There will also be a great deal of aerodynamic research going on which will reveal how best the car can be balanced aerodynamically. The aerodynamics will then dictate the weight distribution of the cars.

There are likely to be two distinct schools of thought, the choice being between a long gearbox or a very short one. Each solution has advantages. A short transverse gearbox keeps the overall weight down. But this will reduce the effectiveness of the rear wing as the airflow will probably be disturbed when it hits the rear wing.

The other solution is a long gearbox. This will make the car heavier and make it more prone to chassis twisting, but it will allow a much better airflow to the rear wing.

The other decisive factor in F1 design is cooling. The current F1 sidepod serves two purposes: it produces downforce and houses the radiators. It is no coincidence that pods are long and thin as these are the best way to maximize cooling.

Radiators can only handle so much air at a given speed. If air hits them at 200mph they cannot cope and thus sidepods are designed in such a way as to slow air to about 80mph before it goes through the radiator. This is done by having a narrow frontal opening for the sidepod through which air is forced at high speed. Inside the sidepod the air is allowed to expand into a wider chamber and consequently slows down.

Shorter sidepods will result in less efficient radiator air flow and, with engines being more important than ever because of the loss of downforce, good cooling is going to be essential. There may be a lot of research and development into radiator design, but this is already well-advanced because of the needs of turbocharged engines. If a revolutionary radiator can be found, sidepods may change, but otherwise they are likely to remain the same.

Thus in addition to restrictive regulations, there are practical considerations which reduce free-thinking in F1 design. This will probably mean that the F1 cars of tomorrow will not change greatly to the design of today.