While the principal objective of the rear aerofoil on a racing car is to provide a down-force on the rear tyres to improve adhesion for cornering and acceleration and braking, the aerofoils at the front are more important to the steering of the car. The static load on the front tyres of a Formula One car is surprisingly small, as can be seen when two or three mechanics lift the front up onto a trestle for easier working. Lightly loaded front tyres will encourage under-steer and a loss of adhesion of the front end before the back end when the limit of cornering power is reached, which leaves the driver in a helpless situation, as was seen when Patrick Depailler crashed while leading the recent Belgian GP. Front aerofoils are designed to improve the adhesion of the front tyres by increasing the load on them by using the wind pressure on the top surface of the front aerofoils. There are two basic schools of thought on front aerofoils, either a full-width single piece layout, or two aerofoils, in each side of the nose. Apart from applying a down-force on the front tyres by reason of the air pressure created by the speed of the car, they can also be used as “trim tabs” to balance the fore-and-aft loading on the car to improve overall stability. If all these things are considered in the light of 150 m.p.h., or the normal flying speed of a light aircraft, some idea of the possible effectiveness of aerodynamics on a racing car can be gained. At lower speeds the effectiveness drops off dramatically, but even at 50 m.p.h. it must still be there even if it is not possible to detect or measure it.
At the moment in Formula One the consensus of opinion among the designers as regards the front aerofoils seems to favour the “canard” fins on each side of the nose, these fins being individually adjustable, or adjustable as a pair from a central point. The aerodynamic form that the fins take depends on the individual designer, for there are a multitude of sections to choose form in the aerodynamic text books. Equally there is a great difference of opinion as to what the fins are actually doing to the air flow over the car. This is seen in the plates on the outer ends of the fins, which vary from virtually nothing, as on the Williams FW07, to enormous plates on the Tyrrell 009. It all depends on whether the designer thinks the air spills off the end of the fin, and if so, whether it is desirable, or on where he wants the air to go after it has passed over the nose fin; some want it to flow uninterrupted under the side pods, others want it to cool the front brakes, others try to feed it into the turbulence form the rotating front wheels.
The RS10 Renault and the ATS favour the same line of thought as the Tyrrell 009, while Ligier, Lotus, McLaren, Fittipaldi, Shadow, very small end-plates to the nose fins, those on the Ligier and Williams being minimal.
Ferrari follow a line of thought of their own, which Ligier used to copy, and that is a single-piece aerofoil mounted ahead of the nose of the car. This is adjustable on a central fulcrum, and also readily detachable complete with the nose-cone so that it is easily replaced as a complete unit in the case of damage, or different aerofoil sections can be substituted very easily. The Ferrari front aerofoil also favours small end-plates.
An entirely new school of thought is being pursued by Lotus and Brabham, the former not yet in racing, the latter working successfully. This is the effective abolition of the front aerofoil. On the Brabham there are no front aerofoils at all, it being considered that the down-force created by the body of the car provides sufficient loading of the front tyres. This is encouraged by the weight distribution of the Brabham BT48, with its relatively long V12 engine and very forward driving position. In consequence the Brabham has a chisel nose-cowling without any aerodynamic aids at all. This gives an added bonus in presenting less drag, as occasioned by the normal nose fins, and it permits a much cleaner entry for the air passing into the radiator ducts in the side pods, and also to the air passing under the side pods.
The same line of thought is seen in the Lotus 80, though here it is more sophisticated (or will be when it is made to work). The original design of the Lotus 80 had a very long nose cowling, without side fins, thus presenting an undisturbed air flow into and under the side pods, but to get a down-force on the front tyres the long nose cowling was utilised. Along each side of the nose cowling were sliding skirts touching the ground and the underside of the nose cowling was open. The air passing under the front of the car was channelled into this opening and deflected to pass out of the nose through an opening in the upper surface just ahead of the cockpit. This air flow was intended to provide a down-force by reason of the low pressure area created under the nose and sealed from the air going to the side pods by the nose skirts. Due to mechanical problems with these nose skirts this system has yet to prove effective, and in the meantime the Lotus 80 uses conventional canard fins. – D. S. J.