Formula One Trend Of Design
DESIGNING AERODYNAMIC aids for the modern Formula One car is one thing, making the best use of them is much more difficult Information about the effectiveness of front to. or a rear aerofoil, has to come from the driver by way offeer and this information 11) turn has to be analysed by the engineer. Adjustments can be infinitesimal or very sizeable in the shape of an entirely different set of fms or a different rear aerofoil, and once again the effectiveness depends on the perception of the driver, or oc.sionally in lap times. Basically, the steeper the angle of the aerofoils to the direction of travel the greater the downforce being applied through the chassis, and thus to the tyres, and the harder a tyre is pressed onto the ground the better it will grip. Balanced against this aerodynamic downforce is the aerodynamic drag caused by the aerofoils, the steeper their angle the greater their drag. In theory you cannot have too much downforce and grip front the tyres and the cornering force generated is proportional to this, but bearing in mind that the aerofoils have to be pushed through the air, you could arrive at the situation of a car having enormous cornering power but no speed, as the b.h.p. of the engine was only just overcoming the drag of the aerofoils. Where mire than one adjustment is available everything has to be a compromise, so on most circuits the aim is to generate as much cornering Iorce as possible without losing any speed on the straights.
On circuits like Kyalami and Paul Ricard, with long straights, you can easily arrive at the situation of reducing drag to a minimum in order to attain maximum speed, but having poor adh.ion on the conners. Alternatively you can produce immense cornering power but suffer from loss of sp.d on the long straights. There is no definite answer, it is entirely up to the engineer to decide what is good for his driver and for the driver to confirm that he feels happy with the result and no two results are exactly the saine. It is alts hit-and-miss game and the best compromises come from a driver/engineer combination that is harmonious.
Types of frontal fins or full-width aerofoils and r.r aerofoils have already been discussed in this seri., and much of the choice is fashion, following the trends set by a successful car. When Lotus were winning with the Lotus 79 with the rear aerofoil mounted on sideplates, there was a lot of copying. Then Williams began winning with the rear aerofoil mounted on a central pillar and that was suddenly in vogue. The adjustments for the aerofoils vary quite considerably, frorn pre-set aerofoils that are changed complete with the mountings, as on the Ferrari, to movable aerofoils with degree graduations marked off as on the Renault. On the Renault the fore and aft aerofoils are hinged along one edge and move about an arc in guide-slots, with locking devices to fix them at the desired angle. On the nose of the car and on the fixed portion of tho rear mounting arc fine graduations clearly marked so that the aerodynamic surfaces can be raised or lowered a degree at a time. When aerotbilS were in their infancy there were few rules and driver control of the adjustment was popular, but the rule-makers banned this and now you are only allowed to alter the angle of incidence of an aerofoil while the .r is in the pits and they must be locked in place.
Most designers mount their front fins on a tube running through the n000 slobs kver and screw adjustment for rotating this tube in either direction, thus altering the angle of incidence of the fins. Sometimes the screw adjuster stands proud of the fibreglass nose, in other cases it is inside and reached with a screwdriver poked down through a small hole. Renault, Brabham, Williams, Tyrrell and Shadow all have degree markings on the bodywork against which to align the edge of the fins, while others have them prc-set at a base angle and then work on the number of turns of the adjusting screw, either one tuni up or one turn down, it being ascertained in the design stage what the ratio of turns to degrees is. Ferrari is entirely alone on front aerofoils, using one very wide one, made of aluminium, mounted well ah.d of the car, like an air shovel. The aerofoil is attached to a tubular structure, with a magnesium casting at the attachment point, and the tubes slot into locations on the front of the monocoque. Three quick-release pins hold the assembly to the chassis and the whole thing can be changed in a matter of .conds. A selection of different size and different shaped unit.= taken to each circuit. Rear aerofoils mounted on a central pillar are the most popular layout and in Most cases the pillar is attached to the gearbox casting by a long,. bolt about which the pillar can hinge. Another bolt locatos through a hole in the pillar which hoes up with any of a number of holes in the mounting bracket. This method allows the incidence of the rear aerofoil to be altered quickly and easily by pulling out the locating pin, hinging the pillar to line up with another hole and inserting the pin. Onoo again, in the design stage the pattern of locating holes is co-related to the angle of incidence. This popular method was perfected by
McLaren a long time ago and copied by numerous designers as being a simple and effective solution. Another method is to pivot the pillar through an arc with clamp bolts in slots to give infinite adjustment, ands spirit level laid fore and altos the aerofoil will give the required angle.
With improvements in the effectiven.s of the air passing under the car the sizes Of front fins and rear aerofoils has been drastically reduced and the fashion now is to do away with nose fins altogether. So far experiments in doing away with rear aerofoils have not been very encouraging, but if sufficient downforce can be created by the bodywork then we may see the disappearance of the rear aerofoil. As the recent 13elgian GP Brabham, Lotus, Williams, Ligier, Fittipaldi, Tyrrell and ATS were all running in the race without nose fins, which indicates a very distinct trend of design. or a fashion. — D.S.J.
More VEV Odds and Ends
TH 1 ‘s t.c.,, 11 V( Run from London to Milton Keynes. sponsored by Milton Keynes Development Corporation, StartS frOITI Alexandra Palace, N. London. and goes via Muswell Barnet, St. Albans, Dunstable and Bletchley to finish at Central Milton Keynes. the date being September 21st. Before this the same Club has its Commercial Vehicle Display with which is incorporated the Vintage Lorry Driver of the Year Competition. and the National Fire-Engine Contest, at the Royal Showground, Sttineleigh, Warwickshire over the week-end of August 23n1/25th. Details from: S. Burborough, 68, Coombe Drive, Dunstable, Beds. ‘rhoo interested in the older “heavies” may care to note these dates.
The Daksman for No March had an article recalling the famous break hill-climb at Rosedale Abbey Bank in N. Yorkshire, known to motoring folk as the Rosedale Chimney. Apart from sonic interesting information about the road it qelf, it See= that the “Chisimey” was first o,c’d000 freak hill-climb in 1919, by the Bradford MC &. LCC. Large numbers of onlookers gathered m see the fun in 1920 and 1921 and were pleased when the local rider, Arthur Champion of Rosedale. won by O point from Moorhouse, riding a 1911 123½ h.p. BSA. From 1923 the York & DMC combined the Sutton Bank speed hill-climb with the Rosedale Chimney freak climb over one weekend. The Bradford MC & I.CC also used the latter hill, after their members had attended a Stmday service conducted by the Rev. 0000000. They had a brass band playing and made the White Horse Hotel at the foot of the hill their headquarters. Champion now had an AlllefiCall Excelsior motorcycle, which won the solo class, the side-car section going to Wood’s Scon Squirrel. The car boys then got the id.. a ster performer being Archie Frazer-Nash in his GN. Jowett driven by W. Cannery 0000 000 of the last to use the gradient, on an occasion when his friend’s Crossley fabric saloon broke down and had to be rescued by a breakdown truck t’rora. Kirbymoorside, the friend being Joe Hepworth of Hepworth & Grandage, the piston-ring peoPie, who had raced a Jovvett at one tinto. Other freak hills were Post Hill (I in 11,, against the reputed 1 in 21/2 or I in 3 of the “Chimneyn, Hepolite Scar near Bradford and Dalton Bank Huddersfield. A variant was a siou hill-climb, tn Garroway, in 1919. Incidentally, the Rosedale Chimney, dismantled in 1972, carried ,Inae from steam engines used to haul ironstone waggons up the incline from Hollis Mine: the bridge taking the baisk over the incline is still stancling.—W.B.