Has Bodywork Design
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Reached Its Zenith?
Until Conventional Practice in Chassis Construction has been Abandoned, Little Advance in Scientific Body Production will be Possible, According to a Contributor who has Made a Close Study of the Many-sided Aspects of the Subject
IT is evident that, at present, improvemint in 'body design is difficult, but the responsibility for the creative lull cannot be laid at the 'door of the body designer alone. It is, in many respects, due to conventional chassis layout. Bearing in mind the fact that the present decade is one of speed, and that, in transport, increased speed, with economy, is the ultimate goal of all power-unit producers, it seems natural to suppose that the streamlining vogue, as applied to passenger vehicles, even with the existing restriction on speed, has come to stay.
Viewing the "streamlined" bodies of to-thy, it is no exaggeration to state that only the effect of streamlining is achieved, and that by means of blatantly swept mouldings. Why is this so '! Is it because, in practice, true streamlining is out of the question, or that exterior mouldings and paint lines swept in an elaborate manner are sufficient to give an impression of flowing bodywork?
One cannot imagine an egg-shaped body designed to give the operator sufficient reason to believe that he can run it at a profit, despite a reduction in the number of seats caused by the loss of headroom at the rear. Body designers are aware that before they can reduce wind resistance, and produce a suitable contour to achieve that object, they must put their case before the chassis designer and invite him to plan a chassis that will lend itself better to genuine streamlined bodywork.
Drawbacks of the Half-width Driver's Cab.
Consider the coachwork of the present day, as fitted to the forward-control chassis. The half cab mars the symmetry of the front of the vehicle, besides leaving an air pocket under the canopy on the near side. Of all things essential in this connection, a completely enclosed front is one of the most important. But how can this object be attained without coming up against the difficulty of engine accessibility, not to mention the fumes from the engine permeating the interior of the vehicle and the amplification of engine noise.
On vehicles having totally enclosed fronts, the ingenuity of the body designer is put to the test in overcoming the accessibility problem. An instance which the writer has in mind is that of a body, the floor of which, immediately inside the "engine door," forward of the near-side bulkhead pillar, is made to hinge upwards, so that easier inspection of the engine is possible. A lamp is fitted in a lower position to light up the darkness caused by the bodywork shadows. Even with such provision for maintenance, it must be borne in mind that the engine is still required, on some occasions, to be wholly withdrawn from its housing.
The difficulty of engine accessibility has been sufficient to dissuade many body designers from producing totally enclosed fronts. Yet of all things a smooth front panel is an essential element of the design of a streamlined body. Has not the chassis of to-day reached a stage when serious consideration should be given to the arrangement of its components, to bring it more into line with the requirements of genuine streamlined coachwork?
Factors Influencing the Position of the Engine.
It would seem that no general transformation in the position of the engine will take place for some time to come. But there are signs. Manufacturers of chassis with side-mounted engines are still producing this type, and, there. fore, it may be surmised that they are practical and commercial propositions. Furthermore, the new axial engine may be setting an example in reducing the site of the power unit, and, apart from its other qualifications, may be an asset to the layout of the chassis from a body designer's point of view, inasmuch as chassis manufacturers may, with smaller engines, be tempted to take them from the front and place them elsewhere.
It is the writer's opinion that the question of engine accessibility, and the necessity of increasing the seating accommodation, will play a great part in keeping the engine at the side of the chassis. Whatever change takes place, it must be an improvement on the half-bonnet type.
Consider, for a moment. the case for the engine at the side. First, seating accommodation can be increased, the front of the vehicle may he properly shaped, and a driving position giving even better forward vision than is at present obtainable on existing chassis can be arranged, The driver's comfort is also greatly improved.
Regarding the bodywork, there are advantages to be gained. The doorway may he placed alongside the driver "under his eye." The body ,rnay he lightened by eliminating the front bulkhead, which is essential with the half-bonnet type of chassis.
In the case of the rear-engined chassis, if the power unit could be placed behind the back axle and at the side, even greater advantages would accrue. There can be a great saving of weight in connection with the transmission items, the number of traps cait he reduced, the chassis frame forward of the hack axle can be lower and can be devoted almost entirely to the will of the body designer. A lower centre of gravity can be obtained, with better braking potentialities, and, altogether, lower body height results—a great advantage from the streamlining point of..
A chassis having these virtues would, indeed, be an advance along the right lines. There is, in fact, a rear-engined bus in service in this country—another sign that the conventionality of chassis design is beginning to lose its hold.
The Frontal Design of the Double decker.
The double-decker has more need than any other type of body for correct frontal arrangement, and careful attention in this connection, especially where a fleet of vehicles is concerned, may result in an appreciable yearly saving in operating costs. It is obvious that a waste of power must be experienced in overcoming wind resistance (the frontal area of a double-decker is about 100 sq. ft.), and the saving over the year on the petrol consumption is considerable when a fully enclosed front is incorporated in the design of a vehicle.
The necessity of breaking away from conventional chassis design cannot he more apparent than at the present time. In the near future, it is hoped, conditions generally governing road transport will have been improved. With greater speed, the need for a nearer approach to streamlined bodywork wilt become axiomatic.
It may truly be asserted that the advance in the design of the bodywork of the not-too-distant future will be the outcome of the researches ot that school of thought in chassis design which, forgetting the term " conven• tionality," allows the body designer greater freedom than he now enjoys in producing scientifically sound coachwork. Until that time arrives, body design can practically be considered as having reached its zenith.