Opinions and Queries
Page 62
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Greater Power: Greater Profit MANY of us who sell British commercial vehicles overseas were pleased to read Mr. P. A. C. Brockington's article, "Greater Power Can Reduce Costs" (June 1). We do not agree with every word of it, but it touches upon some basic facts which ought to have been realized long ago by British operators and designers. Only general understanding of these facts can create a united opinion which could ultimately sweep away the restrictions that have for many years hampered commercial-vehicle operation and development in Britain. Only when this happens, and when designers have adjusted their outlook accordingly, will the British commercial vehicle industry become fully competitive in world markets.
The restrictions I have in mind are the speed limits and the lack of modern motor roads that permit highspeed operation. Too much money and ingenuity have been spent in keeping down unladen weight and fuel consumption at low speeds.
However desirable these ends may be, many British designers have gone too, far and have achieved these objects at the expense of more essential characteristics, such as ability to maintain a high average speed and to do a maximum of useful work in a day. Whenever operation is not hampered by the peculiar handicaps existing in Britain, the capacity for high average speed and maximum output of work has been the supreme factor in overall operating economy.
Even an increase from 20 m.p.h. to 30 m.p.h. in the speed limit on heavy goods vehicles will still leave Britain far behind those countries where 35-45 m.p.h. is the normal cruising speed and 50 m.p.h. is safe even for heavy lorries drawing trailers. A network of modern roads is needed to permit these speeds to be attained.
National differences in topography, climate and road conditions would present a minor problem to the manufacturer who was willing to offer optional ranges of equipment, gear ratios and so on, for vehicles of basically similar design for all markets.
This is impossible, however, when national conceptions of what a vehicle must be able to do to be economic, differ. Mr. Brockington said that in Australia, Canada and South Africa, operators had the American mentality and preferred a powerful engine, as opposed to the British attitude of assessing a vehicle's worth in terms of ton-miles per shilling of operating costs.
Judging by registration figures for countries with such widely differing conditions as Sweden, Norway, Holland, Belgium and Denmark, Mr. Brockington is mistaken when he says that the British view is shared by some smaller European countries.
I know Norway and Denmark particularly well. In both these countries, a powerful engine is a good sales point. The Norwegian buyer wants it because of the many winding roads and steep gradients. The Dane requires it because, on his smooth and mostly level roads, it enables him to maintain a high cruising speed without undue engine wear, or to haul a trailer. Their primary reasons for requiring more power are the same—to do more useful work per day.
So far as I can see, the main difference in outlook is that the British operator is likely to overestimate the importance of costs, whereas overseas operators put the emphasis on profits, which, of course, involves both cost and revenue.
c24 In their efforts to reduce cost per ton-mile, some British designers have lowered the power-weight ratio far below the standards required overseas to enable a vehicle to do a maximum of useful work and to produce the greatest possible revenue.
The operator has two ways of increasing his profit. One is to cut costs without a corresponding reduction in work. The other is to increase the number of tonmiles, even at the expense of higher costs. British users seem to be concerned mainly with the first possibility, but the second offers greater scope for larger profits wherever operating conditions offer increased facilities for vehicle "productivity."
Last year, a leading British manufacturer announced a new series of 5-ton oilers, costing and weighing no more than the average British lorry in this class, but with engines developing about 15 per cent, greater torque than their nearest competitors. Taking the example of such a vehicle, the items most likely to increase when a larger engine is used amount to little more than half the total operating costs per mile. If a 15-per-Cent. larger engine will increase productive tonmileage, by, say, 20 per cent., which is quite common, the operator can afford to pay more per mile for fuel, lubricants, tyres, repairs and depreciation, and still raise his overall profit.
My own experience on the Continent indicates that a 20-per-cent. rise in productive mileage by using a 15-percent. larger engine, would, on the average, increase the cost per mile for fuel, oil, tyres. 'repairs and depreciation by some 15 per cent. The greater mileage yields 24 per cent. more gross profit.
In fact, I have often seen productive ton-mileage raised by 20-25 per cent, with only 10 per cent, more engine power. This is possible under British conditions, even with the present speed limits and traffic congestion.
This is especially true where much tractive effort is used to overcome rolling resistance, such as when carrying building materials over poor roads, or working in gravel pits. If, in such a case, a laden 5-tonner has a rolling resistance of 600 lb. and by raising the engine torque by a tenth, the tractive effort in top gear is increased from 800 lb. to 880 lb., the surplus traction available for acceleration and hill-climbing would rise by at least 40 per cent. from 200 lb. to 280 lb. This means so much in average speed and reduced need for gear-changing that 25 per cent. more daily ton-mileage will often result.
The use of a trailer, which is generally the case in medium and long-distance haulage in Denmark, would have a similar effect on productivity. On a good Danish road with few hills, a 5-tonner with a top-gear tractive effort of 800 lb. can haul a gross train weight of about 151 tons and maintain a satisfactory average speed. The total payload would be about 101 tons. But with an engine developing 10 per cent. more torque the gross train weight can be raised to about 171 tons without sacrificing speed, thereby increasing net payload by some 2.4 tons (about 22 per cent.).
In this case, not only is total revenue improved, but costs per ton-mile are reduced, so that profit is raised by 30-35 per cent.
Copenhagen. Denrnark. AXEL MORTENSEN.