BRITAIN’S AIRCRAFT HIGHLY DEVELOPED DESPITE LACK OF GRAND PRIX EXPERIENCE
AMONGST the many arguments, some practical and some otherwise, which have from time to time been advanced in favour of Great Britain building Grand Prix racing-cars, is that of technical development. How, was it asked, could our engineers keep abreast of all the latest improvements in design of the internal combustion engine, in competition with foreign designers who were always experimenting, regardless of cost?
One could almost have introduced the situation into the recent propaganda film, “The Lion Has Wings,” where British love of the arts of peace is contrasted with goose-stepping Germans, Hitler’s raucous utterances with the genial bellows of bookies on the race-course, etc. Where Britain turned out family cars for peaceful touring, German technicians might have been depicted striving might and main to develop their engines for bombers and fighters. Perhaps it is as well that such a comparison was not drawn, or public opinion of the value of motor-racing would at any rate not have been improved. That Grand Prix racing does produce a highly developed form of the internal combustion engine is undoubted. An output of 100 b.h.p. per litre is now scarcely enough to enable one to hold one’s own even in a long-distance race, and on the smaller cars 150 b.h.p. per litre is being realised—alas, alter all verbs to the past tense. Yet a touring or sports-car which develops even 40 b.h.p. per litre is something of a phenomenon (one can still refer, if only just, to sports-cars in the present tense). What, then, of the British internal combustion engine, a term applying equally to both car and aircraft power units? Has it lagged so far behind? Happily for our peace of mind, and for the peace of the world, it is now certain that British aircraft are more than a match for their German rivals, even without the stimulus to design gained from Grand Prix racing.
Although the writer would deprecate any statement which could be construed as contrary to Grand Prix racing, the most spectacular sport on earth, the fact of the matter is that a Grand Prix engine is so highly specialised and so costly to build that lessons learnt from it can only be applied indirectly and very gradually. Such engines propel an extraordinarily small and light car at an amazing velocity, and in view of the resultant spectacle are well worth while, in the opinion of most enthusiasts, at any rate. Also they do breed a feeling of respect for the engineers who built them, and hence have a considerable prestige value.
The same applies to the chassis, but to a lesser extent. Front wheel brakes, for instance, though not actually first used on racing cars, as many believe, owed their development almost entirely to racing, and it was a simple matter thereafter to apply the principle almost direct to touring cars. In modern times independent suspension has received a similar fillip. Chassis development, however, as not applicable to aircraft, is beside the point here. It is the engine which we are considering, and the use which may be made of Grand Prix lessons. The first great limiting factor is the nature of the fuel used. Many have used this argument against Grand Prix racing-cars in general, as built under the last two formulas. The French, in particular, have for years advocated a restriction on the type of fuel allowed, on the ground, that development was being led on the wrong path, with engines drinking up methylated alcohol and nitro-benzole. Such an objection is justifiable, if one is looking solely for quick and direct application of racing lessons to engines for other types of work. Supercharger pressures and compression ratios, to mention only two factors, have risen much too high for any comparable results with ordinary fuel, even such as is used for aircraft. The whole of the Grand Prix engine, as built by the Germans with such success, has been based upon ability to use the fuel which produces that marvellous “boot-polish” smell.
With such fuel, however, the 3-litre Mercedes-Benz was only capable of about 2 m.p.g., and the French at one time hoped to offset the inferior speed of their 4½ litre unsupercharged cars by the fact that they would have to fill up less frequently. That such a hope was not realised was illustrated in the French Grand Prix last July, when two of the Talbot-Darracqs ran non-stop throughout the entire race, and yet were three laps behind the winning Auto-Union.
Aircraft cannot call at the pits during a bombing raid to refuel, and even the short range fighters already suffer a handicap through having to return to their base for more fuel after a limited time in the air.
Fuel consumption is thus of even greater importance for aircraft engines than in a long distance race, and it may readily be seen that direct application of the principles which produced so much speed and power for the Mercedes-Benz and Auto-Unions is hardly possible, even when one realises that the same firm, the Daimler-Benz is responsible for one of these cars, the Mercedes, and for a great number of the German aircraft engines.
This is not to say that the Daimler-Benz engineers have not benefited from their racing experience, for they must have learnt under the last two G.P. formulas how to build their engines light, and the science of light alloys has certainly been much advanced. Reduction of weight for aircraft is of vital significance, even it if only enables one to carry more fuel (or bombs).
Indeed, for aircraft development a G.P. Formula which included the weight of the fuel with that of the car in its restricting limit would be excellent. Neither of the last two formulas has had such a clause, cars coming to the weighing-in with empty tanks, and, during the 1935-1937 formula, without tyres on the wheels.
One might have said before the 1939 season that the German designers had also learnt to build their racing engines strong and reliable. The results of the French and German Grand Prix, however, in both of which races only two German cars finished, rather dispelled that idea. While one would hesitate to dub the 1939 Grand Prix cars as definitely unreliable, one must certainly allow a greater factor of safety for an aeroplane engine, than for a racing car, and thus again the direct application of racing practice is limited. On a racing car reliability is desirable. In an aeroplane it is essential. Many have scoffed at the huge cars produced by British designers for attacks on the land speed record. Why should over 36,000 c.c. be necessary for 300 m.p.h., they asked, when others reached 270 m.p.h. with engines one-sixth of the size? One answer is immediately apparent, that in Great Britain we already had large aeroplane engines capable of delivering the necessary power, whereas the smaller, highly efficient types of power unit had not been developed.
Capt. G. E. T. Eyston, however, told the writer that for his part he definitely preferred the big machine, as possessing an infinitely greater factor of safety. The Rolls-Royce engines in “Thunderbolt” were similar to those in the fighters and bombers that we hear roaring overhead. Can it be denied that Sir Malcolm Campbell and Capt. Eyston have played their part in developing exactly that type of engine which is most useful to British aircraft at the present time?
There again, the engines in “Blue Bird” and “Thunderbolt” were of racing type, and, again, special fuel was used. It was estimated that “Thunderbolt’s” two engines burnt fuel at the rate of eight gallons per minute! But the engines were not entirely different productions, like those of Mercedes and Auto-Union, and were merely developments of the service type of Rolls-Royce aircraft engine. This engine owed much, indeed, to racing, but not to Grand Prix. It was the Schneider Trophy series which enabled British engineers to demonstrate their mastery in this element. At a time when Italian racing-cars were at the top of the tree, Britain took the Schneider Trophy with her seaplanes at Venice in 1928, retained it against formidable opposition over Southampton Water in 1930, and won the Trophy outright in 1932, when none dared to appear to contend it.
If the Air Ministry had really instructed British –designers to get down to work for a fresh Schneider Trophy series in the last few years, in the same way that the Fiat factory was turned from racing-cars to racing aircraft in 1928 by order of the Italian Government, few would fear the result of a contest against the Messerschmitts and Heinkels, despite the racing prowess of the Daimler-Benz.
We knew it would happen one day, and it has. In “The Light Car” of December 9th, “The Blower ” thinks that it’s rather odd that while the Right Crowd refuses to regard midget car racing and cinder-track racing with any degree of seriousness, the same Crowd will go to Shelsley or Prescott and watch the uncertain prowess of Shelsley-Specials with every mark of respect. What “The Blower” loses sight of is that midgets are freak machines constructed solely to provide a spectacle for the less-well-informed section of the public. They do not motor at real racing speeds and, from what we have seen of them, they are not so consistently reliable as Shelsley-Specials, taken in general. They attract only because showers of dirt emanating from noisy machines all of identical performance and calling for a specialised skill in handling, does represent a rather thrilling spectacle. Our quarrel with such racing is that it does not serve to better the breed and that if a fatality occurs through careless staging, as has nearly happened so often at Lea Bridge, that accident will be broadcast in the :sensational Press to the detriment of motor-racing in general. The Shelsley Special may be equally far removed from conventional practice and teach equally few progressive lessons, but it is built to motor under natural conditions, at speeds which the better cars attain on the road. Enthusiasts are interested to see how these specials run under natural road conditions and how they respond to ordinary driving methods. Most of them are a thought more potent than the Austin Seven wheelbase, 12-inch wheeled midgets built under American midget-speedway rules, nor have we seen one crash so horribly as the midget pictured in the heading to this article in ” The Light Car.” Let us have midget car cinder track racing by all means, if there is a demand for it and it can be had without wholesale slaughter and injury. It might provide a pleasant fill up during the war. But do not let us commit the sacrilege of comparing midgets with real V-twin, chain-driven sprint racing cars.