All the signs in the paddock showed a very healthy situation in Formula One and -a good start to the European season. There were no fewer than 46 competitive cars on hand, of which 10 were brand new cars, and among them were four brand new designs. There was the Lotus 79 in its latest form, a pair of new TS20 Surtees cars, the new Ligier JS9 and a startlingly new Wolf. In addition to these there were new cars in their current series from Brabham-Alfa Romeo, Ferrari, Shadow, McLaren and Arrows. All in all, a truly impressive collection of machinery.
With engine power, whether it be from a Cosworth V8, a Ferrari flat 12, an Alfa-Romeo flat-12, a Matra V12 or a turbo-charged V6 Renault, more or less equal, give or take a few horsepower, and suspension knowledge known to everyone, designers are trying to get an advantage over their rivals by aero-dynamic means. Trying to control the air flow to the car’s advantage by nose fins, cockpit shapes and rear aerotbils has been exploited to the maximum, now the trend is towards using the air around the car as a whole. There are various routes to take, either preventing any air from going under the car, and utilising the air flow over it, or encouraging the air to go under the car and then controlling it to create a suction to draw the car down onto the track. Whether you try to suck the car down, or press it down from above, the object is to load the tyres for increased adhesion in the corners, or under braking and accelerating. Different designers take different routes, Gordon Murray on the Brabham BT46 has a vee-shaped skirt under the nose of the car to deflect the air sideways, and similar skirts along the sides of the car to stop air getting underneath. These skirts are of’ a special plastic and rub on the road surface continually. A smooth flow over the body utilises the air in the nose section and over the tail and rear aerofoil. McLaren designer Gordon Coppuck follows a similar route. Cohn Chapman takes the opposite way, he encourages the air to flow under the car, and flexible side skirts keep it underneath until it can escape out the back. In its passage under the car It is forced to follow an inverted aerofoil section, which creates negative lift, or suck. Tony Southgate followed this lead on the Shadow DN9 and took it with him to the Arrows FA1. Now Harvey Postlethwaite has joined this school of thought with his new Wolf WR5, designed and built in an incredibly short time since the Brazilian GP.
The normal Cosworth V8 exhaust system has a bunch of four pipes on each side of the engine, gathering together into their own tail pipe running low down under or through the rear suspension. The bunches of pipes block the passage of air along the side of the car, so both the Wolf WR5 and the latest version of the Lotus 79, have the pipes curling upwards over the engine into tail pipes above the gearbox, the Wolf having long tail pipes, the Lotus having short ones. The two tail pipes, very close to each other, make a new sort of music on the Formula One scene, giving a very high pitched note compared to the normal Cosworth sound. Whereas the Lotus uses flexible side-skirts that bend as the car rolls or goes over bumps, the Wolf uses a rigid skirt that moves up and down in a slot in the side pod, on each side of the car. These skirts are hung on thin strip wishbones anchored to the chassis on ball-joints so that the whole skirt can rise up or down, or it can rock for-and-aft. At the front is a metal skid that can ride over a bump or a kerb, and in so doing a system of levers lifts the skirt out of harm’s way. When being moved about the pits or paddock the skirts are lifted up by hand and held up by the insertion of a locking pin. The two pins are joined by a plastic chain looped over the engine bay, which ensures that Scheckter does not go out on the track with the skirts in the up position. When the pins are removed the skirts drop down into contact with the road, under their own weight, and there are stops to prevent the skirts falling out of the guide slots if the car becomes airborne.
While the Lotus 79 retains the “winklepicker” or “needle” nose form of the previous designs, with side fins, it no longer carries the oil radiator in the nose; this is now carried in the left-hand side pod, and the water radiator is in the right-hand pod. The Wolf WR5 has abandoned this type of nose and uses a Ferrari-type, with a hill-width aerofoil mounted on an outrigger ahead a the front bulkhead on the monocoque. In the centre is a graduated knurled knob tor adjusting the angle of this aerofoil. The oil radiator has been moved to a position on the scuttle, in front of the driver and above his knees, with heat resistant foil and deflectors to keep the heat out of the cockpit. Front suspension on the Wolf is entirely new, with sturdy doublewishbones, with the top one extended inboard to operate the coil spring/damper unit. The Lotus 79 has changed from a box-section upper rocker arm operating the front spring, to tubular wishbones, while at the rear there are new tubular wishbones controlling the lower ends of the hub carriers. The major change at the back of the Lotus 79 is a complete redesign of everything in order to take a standard Hewland gearbox in place of’ the Lotus-Getrag gearbox, which has been withdrawn from service for some further development and design.
Almost everyone has now copied the adjustable rear anti-roll bar mechanism, introduced by Lotus some years ago, in which one arm of the roll bar is in the term of’ a blade of steel which can be rotated about its longitudinal axis by a lever in the cockpit operating a Bowden cable and a link system. The stillness of the anti-roll system depends on the angle of the blade, presenting maximum stillness at one extreme to minimum when turned at 90-degrees. Even Ferrari has now adopted this system, having tried the complicated sliding mull arrangement at Long Beach. Any Formula One car without an adjustable-from-the-cockpit rear anti-roll bar is behind the times. The new Lotus 79 now has an adjustable front anti-roll bar, operated by a pushpull control on the felt of the instrument panel. Other designers will probably take note. The bodywork on the new Lotus covers the mechanical components completely, as well as the up-and-over exhaust system, which kept blistering the black paint and making a nasty smell of scorching fibre-glass. The rear aerofoil is mounted on side-plates and the bodywork flows into these. The Lotus 79 first appeared on test last winter, but that prototype was scrapped and 79/2 appeared at the International Trophy at Silverstone, only to suffer major damage when Andretti slid oil the road and hit the new Shadow DN9. The impact wrote off the felt front corner and the force of t he blow shock-waved through the chassis and tore the right-front engine mounting out by the roots. During its major rebuild the whole back-end was redesigned to take a Hewland gearbox, so that Lotus 79/2 is now in a sort of Mark 3 version of the initial 79 design.
The new Ligier JS9, using a lighter Hewland gearbox joined to the Matra V12 engine by a long cast-alloy spacer, to give a longer wheelbase than the normal JS7, concentrates on improved airflow over the car rather than under it. The monocoque is of a much smoother shape with a smooth hump over the engine behind the cockpit that deflects air onto an enormous rear aerofoil that joins up with the main bodywork and is mounted on sideplates that are extensions of the body. The basic layout of the suspension is unchanged, though the sizes of things and the geometry has been tried out on the interim JS9/JS7 car. A full-width front aerofoil is retained.
The Surtees TS20 design embodies much of the thinking of the TS 19, with triangular section monocoque, but the water radiators are sunk into the sides of the engine bay, lying flush with the sloping sides of the monocoque. New double wishbone front suspension, with rising-rate geometry for the coil springs is used, and the fullwidth nose of the TS19 has given way to a needle nose with side fins. Due to having two different sponsors John Surtees was in the invidious position of having to build two new cars before the design could be tried under racing conditions, as each sponsor wanted the new car. This stretched the working capacity of the Edenbridge team to the maximum, and it meant they were short of vital spares, particularly for the clutch mechanism, which gave trouble in practice. Brambilla drove TS20/01 and Keegan drove TS20/02 during practice, but neither car raced.
Five teams had new cars to existing designs, Brabham producing BT46/5 for Watson, so that BT46/3 became the team spare, with Lauda retaining BT46/4. However the new car had something fundamentally wrong with the front suspension, so Watson changed to BT46/3 during practice and also used it for the race. None of the Brabham cars were using the carbon-fibre brakes as these have been withdrawn for further research and development. Ferrari completed 312 T3/035 and it was brought along as the team spare. Reutemann tried it briefly in practice, but used 312 T3/032 for the race, and Villeneuve used 312 T3/034. All three cars had the new type of adjustable rear anti-roll bar, and new rear aerofoils with small box-kite style appendages on each rear corner. The Shadow team completed another DN9, the fourth in the series, which Regazzoni used, while Stuck kept to DN9/1A. The Arrows team also completed a new car, FA1/3 which was given to Patrese, but he clobbered a corner and creased the monocoque, so took FA1/2 for the rest of practice and the race, though this was nearly destroyed by him in the last practice. Interestingly, the impact with FA1/3 was short and sharp against the steel barriers, and the shock-loads bent a front wishbone, wrecked the steering rack and transmitted the blow directly into the monocoque, which deformed. The accident to FA1/2 was a long lingering one, bouncing and rubbing along the guard-rail until the kinetic energy was expended, during which time bits and pieces were ripped off the monocoque, but the structure itself received no direct shock loads, so did not deform. It: the kinetic energy of a mass, be it a car or human being, can expend itself at its own rate of deceleration, little damage will be done. If the energy is absorbed abruptly, by contact with a solid object, the damage can be extensive. This is why you can fall off a motor-cycle at 100 m.p.h. and slide to a stop without damage, provided you do not hit anything, yet can break an arm or a leg falling over at 5 m.p.h., if your vertical energy is absorbed abruptly by hitting the ground.
The last of the new cars was a new McLaren, number M26/6 built to the order of Brett Lunger and the B&S Fabrications team. For the rest of the 46 cars in the paddock they were all the regular runners. The Tyrrells were 008/3 (Depailler), 008/4 (Pironi) and 008/1 the spare. Lotus has 78/3 for Andretti and 78/2 for Peterson, with no spare, as 78/4 had been sold to Hector Rebaque and painted brown to match his first car, 78/i. McLaren had M26/4 (Hunt), M26/6 (‘rambay) and M26/3 as spare. The two Penske cars modified by March for Nis were as before, apart from new, sleeker cockpit surrounds. Fittipaldi had his two Copersucar sponsored cars, F5/2A and F5/3A, looking more and more like Lotus 78s in mechanical detail since Ralph Bellamy has been to work on them. Renault had RS01/02 and 03 with changes in the turbo-charging layout, to get better pick-up, and were back to the NACA duct intake for the turbo-charger, in place of the horn used at Long Beach. Scheckter had WR1 as a spare to the new WR5 Wolf, but used the old car for the race, it being the car he won with last year, though it has been revised in detail for this year. Ensign had MN06 which Ickx raced, and MN08 as their spare, having sold MN07 to the German sponsors of Harald Ertl. The Hesketh team had numbers 4 and 5 in the 308E series, and Daly damaged number 4 in pre-practice qualifying. Laftite had JS7/03 in short-wheelbase form as a spare to the new J59, and Jones had Williams FW06/002 as spare to FW06/001 which he raced. Lunger had his M23/11 in reserve but did not use it, its nose cowling and oil radiator having been altered to M26 form. The Martini MK23 was driven by Arnoux, while Rosberg had the Theodore TR 1-2, and Merzario had his home-built special now painted black and carrying new advertising. –D.S. J.