Light Weight May Reduce Safety
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IN our issue for last week we published a description of a large-capacity body_ which has been cleverly constructed on aircraft principle's. Considerable use was made of 2 mm. plywood and glue, and the result, no doubt, is proving highly satisfactory from the points of view of minimum weight with a good factor of safety. Whilst the effort is distinctly commendable, why, may we ask, was it necessary for this hauliercum-bodybuilder to go to these lengths to obtain such a body? The answer is to be found in the ridiculous regulations concerning unladen weight, which cramp the style of all bodybuilders and chassis makers in this country; So long as such a system remains vehicles will be built to a lower factor of safety than they need be. Could there be any greater incentive to reduce the strength of component parts when a matter of a pound or two can make all the difference between a vehicle being allowed to travel at a maximum speed of 30 m.p.h. as against 20 m.p.h.? Usually, the "under 60-cwt." machine is built so closely to its permissible weight limit that, after being in service for some time, moisture on the body and any accumulation of road matter on the chassis will actually bring it outside its legitimate weight category.
Good Reputations Easily Lost We have heard in the past of the alleged flimsy nature of some of what were then "under 50-cwt." chassis, arduous service ultimately showing up serious weaknesses in the main frame. Bad news seems always to travel quickly, and hence the maker of a machine in which the highest factor of safety has been sacrificed in order to build down to a weight limit, loses a valuable reputation, which, as a result, is, more or less, suspect for years afterwards.
In the first place, it is sonfewhat unfair to lay the blame on the chassis maker, for, after all, he is endeavouring to supply the best possible vehicle. without being free to do as he would wish. In the second place, the operator, in many cases, is more than a contributory cause of bringing about the premature failure of a chassis by excessive overloading. Owing to the fact that manufacturers have been compelled to use cast iron in major components and steel for panels where light metals were previously employed, it has been necessary for the regulations to be altered so that the maximum permissible speed of 30 m.p,h. now applies to 3-tonners.
Whether there will be a reversion to the old weight limit when lighter materials become more generally available remains to be seen, but, in our view, the extra 10 cwt. would make all the difference to this particular class of chassis. With this additional weight to play with, a maker could, as other parts become lighter, 'employ a frame of deeper section or, alternatively, he could use a heavier gauge of steel, should either of these features have been found advisable as the result of experience. There would then be fewer complaints from, say, operators of tipping lorries in respect of bent, cracked or broken frames.
Bad Effect on Overseas Buyers It must always be remembered that a vehicle which earns a bad name for itself in this country will also be looked upon with suspicion overseas, for, as we have previously mentioned, such news travels quickly and, incidentally, far. Whilst we are fully aware of the way in which the British chassis maker is restricted in respect of giving full effect to his own ideas as to how a machine should be built, it is difficult to make such a story ring true to operators who have no occasion to respect the hundreds of pettifogging regulations which really concern only users. in Britain. So long as the n m.p.h. speed limit applies to vehicles of such a low unladen weight as 3 tons, so long will operators buy these machines when they know full well that, were it not for the considerable advantages attached to the extra 10 m.p.h., they would, particularly for certain classes of work, purchase a heavier type of vehicle more suited to the work which it has to do.
If there must be this difference in speed limits, and we contend that there is no such necessity, why should there not be an intermediate one of 25 m.p.h. to cover vehicles of, say, from 5 tons to 8 tons? Machines up to 4 tons would then come into the 30 m.p.h. class, whilst those over 8 tons would remain in the 20 m.p.h. category. ' As, however, the efficiency of the braking systems on commercial vehicles is in a favourable ratio to the class of machine concerned, there is no logical reason why there should be any differentiation between goods vehicles and private cars.
When considering the problem of unladen weight there is also a further factor which must receive close attention ; this is the amount of licensed tonnage which a carrier in the A and B categories may employ. He cannot, without the sanction of the R.T.C. for his region, replace, say, a vehicle of 50 cwt. by one weighing 3 tons, unless, of course, he has been operating previously a tonnage which was under that permitted to an extent sufficient to allow for the additional weight.
Making the Roads Safer In Winter
AT times like these, when conditions of frost and snow ma:y prevail over large areas of the country, the weakness of the control of our road system, particularly so far as its maintenance is concerned: is brought well to the fore, although, perhaps, " well " is the wrong word to employ !
Chats we have had with road operators indicate the irregular way in which such important tasks as snow clearance and gritting or sanding are performed—and not only in connection with minor thoroughfares. One quite small municipality may do its work of this type most efficiently, and, perhaps, the roads for two miles at each side of its centre will be made comparatively safe, but outside this area the conditions may be vastly different. For instance, quite recently, on an important by-pass, lorries were all over the place, and there was even a Tank carrier, complete with its Tank, overturned into the ditch. The excuse that there is lack of man-power available to deal with sudden emergencies such as this will undoubtedly be put forward, but some of those authorities responsible appear to carry out their work quite well, whilst others either delay suitable treatment or do not carry it out at all.
In such instances, the wastage of carrying capacity and of time and the darnage to vehicles must be considerable. In importance they may far outweigh the cost and difficulty of -providing a little extra labour.
The Government, through the M.O.W.T., is responsible for some thousands of miles of main roads, but a huge mileage is still controlled by county and smaller authorities.
We cannot at this juncture—or, indeed, at any time—afford any wastage which may be caused in road transport, quite apart from the danger to vehicles and personnel which is thereby involved. There is also a considerable risk to other forms, of road traffic, including cyclists, not to speak of that to pedestrians, for walking on icy footpaths and roads is not easy unless they be well gritted, and a tumble may result in injury as serious as the breakage of a limb, which, again, may cause loss of production. Something must be done, and that quickly, to alleviate dangerous conditions as they
OCCIN.