ANATOMY AND THE SPORTS CAR.
A Plea for more Comfortable Driving Positions. THE pundits of the motor world are never tired of pointing out the progress which has been. made in the design of pleasure vehicles during the past ten years. This is undoubtedly true as far as engine efficiency, chassis design and braking systems are concerned, but these developments have overshadowed to some extent the needs of the driver and his passengers. Certain
physical exertion was needed to control cars such as the old 30-98 Vauxhall and the three litre Bentley, the premier sporting vehicles of the day, and consequently designers took care that the driver had plenty of room to get at his gear-lever and his brake, to lock over his steering wheel and also to see where he was going. ‘The raising of the bonnet, the adoption of a low driving position and the ease of manipulation of the modern light sports car have brought with them problems which have not received their share of attention.
The smallest type of car such as the M.G. are usually free from annoying faults of driving position, since the occupants sit, as it were, outside the body, with their outside elbows over the side, while a short wheelbase prevents anything but an upright seat at the wheel. The worst offenders are cars developed from touring chassis, in which the only method of securing the fashionable low seating position is to place the occupants practically on the floor. This implies an upright seat-back so that the driver must sit with his legs stretched out horizontally in front with the greater part of the weight of the legs supported by the heels. This type of body is difficult to enter, puts an unpleasant strain on the legs and often causes an =pleasant cramp of the pit of the stomach after a long run. Another fault of which ever high-class coachbuilders are guilty is to have the seat-back raked back at an excessive angle, so that one is compelled either to sit upright without proper support, or to loll back with loss of control and further discomfort of the central regions. Even on the best of roads the body is subjected to a certain amount of vibration, and if the stomach muscles are relaxed to allow the upper part of the body to swing back, one’s food is subjected to a sort of channel-crossing motion. Nuvolari and other racing men always go
to considerable trouble to obtain a vertical position, and the fast tourist will find that he will benefit from following their examples.
More trouble should be taken with the position of the steering wheel and the rake of the column. The best angle varies according to the distance from the wheel at which the driver is intended to sit and will require to be more upright the closer to it he sits. Large spring wheels have greatly increased driving comfort, since the shoulders remain fully open and the chest is unre stricted. High placed steering wheels are tiring, for the weight of the arms hangs from the wrist instead of the shoulders,
instead of the shoulders, and one also gets restriction of blood flow which means cold hands. A short steering column is tiring for a tall driver, but in many cases the shaft may be lengthened without great difficulty. Driving seats carried with their centres beyond the steering column seem unpractical, but one gets used to them quite
quickly. Body width is determined largely by the size of the chassis and the performance which the finished car is intended to have. On a narrow body the arm and shoulder must obviously project outside, while a wide one pays the penalty of increased wind-resistance, but on one or two cars I have driven lately the makers have struck a most unhappy medium, for my elbow remained firmly wedged between my side and the edge of the body
and my right arm remained out of action till the end of the journey. More cutaway is needed for body sides, with a flap to allow the elbow to project, while much can be done on a closed car by fitting an armhole in the depth of the door. Few points have greater bearing on driving comfort than the placing of the pedals and other controls, and one or all of the points are neglected on present-day
cars. If possible the clutch and brake should be placed at such a height that the heel slides along the floor when the foot is moved up to them, while the ball of the foot should come in contact with the plate. The support of the floorboard is at any rate essential for a steady pressure on the accelerator pedal. The pedals should follow the same axis as that of the leg, but one of the most essential points is that from the normal seating position they should reach the bottom of their travel without the legs having to be straightened completely, or in the case of the throttle pedal without having to stretch the ankle muscles. There is nothing more tiring than trying to urge a car up to the maker’s catalogue speed with the right foot extended as for ballet dancing.
Most people prefer the throttle pedal on the right, for in that position the body should be steadied by the right and left heels on either side of the steering column. “Should be “is deliberate, for in a number of cases I have found that owing to the steep angle at which the ramp board is set, only the toe can be rested on it, a fault which proves very tiring on a long journey. Even more annoying is a car on which there is not sufficient space for the left foot between the clutch pedal and the clutch housing and the gear-box.
Remote control gear-levers have in most cases done away with the need for groping in the “office,” but brake levers are still all too often tucked away out of reach, with the sharp edge of the facia board ready to remove the knuckle of the unwary. The craze for long and high bonnets combined with a low seating position means that on many cars the near-side and even the off-side mudguard is invisible, and precise manceuvring in traffic and in crowded garages is rendered un
necessarily hard. In a thick fog too the driver of the modern car is almost helpless, for he cannot see the kerb closer than ten to fifteen feet in front of the car, while lorry drivers and motor cyclists, who can see vertically downwards, continue to make steady progress. In-their efforts to reduce frontal area, designers are bringing the bonnet lower than before, but with the driver still sitting down on
the floorboards, his range of vision is not much extended.
Well-arranged windscreens are much rarer than they ought to be. For myself I Still prefer the three panel affair as fitted to the three litre and 4litre Bentleys, in which one of the flaps can be Opened for driving in fog. The single panel type no doubt gains in neatness, but coachbuilders are inclined to cut off those extra inches which mean clear vision without bending the neck. A wider field of vision could be obtained even with a narrow sheet of glass if it were brought hearer to the driver.
Another thing. Why are the screen pillars, especially of saloons, of a thickness worthy of an L.G.O.C. bus, and often further obstructed by a driving mirror mounted just in the most blind spot ? The weight of a canvas hood or the roof of a saloon car should not need such massive supports. Sidescreens with a three inch opaque strip at the forward end are not conducive to clear vision either. This catalogue of woes may well end on the question of upholstery. The air cushion has undoubted advantages on the sports car, for it absorbs those small vibrations which stiff springs and shockabsorbers fail to eliminate. On the other hand I have driven quite a number
of cars which no alteration of tyre pressure and ” shocker” adjustment seemed to stabilise, only to find that the uneasy feeling was caused by the rolling of the seat. The new Dunlop cellular filling overcomes this difficulty, but needs to be fairly deep. For shallow cushions a wider use should be made of those air-bags which either contain a number of tubes or the other type with large ” holes ” through them. Every new car which one drives seems to have some snag to which one has to become acclimatised, such as a carefully concealed horn-button, a steering wheel where the gloved hand gets caught up on a switch, the back end of the scuttle or something equally stupid. All designers, I think, ought to be made to average at least 40 m.p.h. for 500 miles on each of their new productions to get a fair idea of their discomforts, and should be com
pelled to build ears which are not intended (a) for a double-jointed dwarf, (b) for a six foot driver with a body 18 inches long and no neck, and (c) for a Siegfeld Folly who never has to wear clothes heavier than a bathing costume, who are apparently the three types of person for whom the average sports car has been constructed. Like the clever boy in ” Eric, or Little by Little,” my criticisms arc not entirely
destructive, and so I give my own idea of a comfortable driving position.
The back of the seat should be sloped back at not more than 10 degrees, and should be high enough to support the shoulders and shaped to engage in the small Of the back. Pneumatic squabs do away with the necessity of making individual measurements. The seat cushion, which must be proof against rolling, slopes back at 10 degrees, and may have a raised portion at the front end to prevent Slipping forward with violent braking. Cars can now be fitted witha special form of seat slide which allows the angle of tilt to be adjusted to suit the individual.
The driver is now supported in a position from which he can best control his car, and one from which sudden changes in speed will not tend to shift him. His legs, principally the left one, are employed to steady him, and to do this the whole foot must rest on the ramp board, with the • foot bent at a natural angle. The upper and lower part of the legs should be at about 45 degrees to one another to give flexibility, and if the left foot is too far away when the right foot is properly placed for the pedals a block should be screwed to the front board to give the necessary support. The heel of the right foot gets its stability on the floor board and for preference should also come up against the ramp. The boss of the steering wheel should be level With the centre of the chest, and the rim should be at a distance such that forearm and uppe4 arm both slope downwards, avoiding both stretching and cramp. Seated in this fashion, with a windscreen giving a wide field of view, and with controls so placed that no effort is needed to reach them, the driver passes from being merely the helmsman of a fast
mechanism propelled by as the licensing authorities have it, and becomes Otte with his machine like the expert horseman and his mount.
How little these needs are appreciated was brought home to me the other day when I drove the experimental and afterwards the finished production of a famous firm. Everything was perfect in the experimental body, but driving the sales manager’s pride and joy I found that one’s feet fouled the steering column, the ramp board was too short for people with large feet, while the passenger’s legs were in danger of being amputated by the facia board each time we went over a bump. Nobody drives his best on an uncomfortable car, and it is up to every owner to search out the weak points and to bring them to the attention of the manufacturer concerned. I don’t guarantee, however, that the fault will be rectified on subsequent cars !
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