The March 711 raced on into 1972 with the independent Williams team, which ran it with a more conventional nose and a single element rear wing
Prix, qualifying fifth and finishing second again behind Stewart. The Austrian Grand Prix on the fast-
flowing Österreichring circuit threw up another problem. Peterson struggled home to an uncompetitive eighth place finish, while F1 debutant, Niki Lauda, was slowest of all in qualifying, and pulled out of the race with handling problems before half distance. ‘If the front wing was tipped up too
far, the downforce disappeared,’ explains Herd. ‘The 711 didn’t work very well on circuits with long, fast corners, and the absolute killer was the Österreichring. At that track we were really stuck in a downward spiral. In a fast corner the aerodynamics are significant and the downforce generated at the front of the car is about 40 per cent. The driver accelerates as soon as he can and as the nose of the car lifts under acceleration, it reduces the downforce so the car tends to develop an aerodynamic understeer. You can live with that for a while on normal circuits, but on tracks with long, fast corners it tended to overload the front tyres because of the understeer. At the Österreichring the drivers found that it was okay for a few laps but it would
eventually get to the point where the tyres would not be able to recover before the next corner.’ The 711 ought to have been perfectly
suited to the high-speed straights and corners of Monza, the venue for the Italian Grand Prix, and to maximise its low-drag potential, the 711’s front wing and most of the elements of the rear wing were removed. ‘The 1971 race at Monza was the last time F1 cars ran at Monza before the chicanes were built,’ recalls Herd. ‘Because of the high speeds, the teams would look to cut drag as much as they could. The 711 was very much in its element at Monza, but it wasn’t as fast as it could have been. Due to finances that year, Ronnie’s engine should have been rebuilt two races before and so was way down on power. Ronnie finished second to Gethin’s BRM by only 1/1000th of a second. With a fresher DFV it might have been different…’ The Monza race also brought to an
end Costin’s involvement with the 711. At the beginning of the project he had agreed to be paid a fee calculated on the amount of effective horsepower gain due to reduction of the aerodynamic drag of the car relative to the 701 it replaced. A method of determining the improvement
End plates are fixed to several of the wings in current Formula 1 use. Their purpose is to prevent air spilling over the sides of the aerofoil, reducing the lift. Air tends to flow from the high pressure beneath the surface to the low pressure above, so creating a trail of ‘tail vortices’ from both wing tips. End plates tend to prevent this end flow, but unfortunately the plate size needed to prevent these vortices must be so large that they create a significant amount of drag themselves. However, with the limited wing span of a Formula 1 car this ‘artificial’ means of raising the aspect ratio has its attractions. Much of this problem can be overcome using an elliptical rather than a rectangular wing shape in plan view – a shape such as was used on the Spitfire.’ Robin Herd, Autocourse, 1968.
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