The Vintagent Archive: Wheels And Wings

How Speed Work varies on Motor Cycles, in a Car, and in Aeroplanes

[From ‘Power and Speed’, published by Floyd Clymer, 1944]

By Flt.-LT C.S. Staniland

Chief test pilot, Fairey Aviation Ltd, Motor Cyclist and Racing Driver

 

I suppose that, before I begin writing about aircraft and motor racing, I had better tell you how I first came to be mixed up in this business of fast moving in the air, on four wheels and on two.

I have been keen on machines all my life. Racing cars, motorcycle and aeroplanes have fascinated me for as long as I can remember, and the men who performed great feats in theses spheres were my heroes at a very tender age. My very first machine was a motorcycle. Just after the war motor cars were fabulous machines costing a king’s ransom, or so it seemed, and when young men were infected with the desire of travelling fast, it was usually to motorcycles they first turned, graduating on two-wheels before moving on to four-wheelers, and so it was in my case. My first taste of the joys – and tribulations – of mechanical transport was found on my brother’s motorcycle, which was a 1911 Douglas – a very famous machine in those days on which many a well-known personage in the sphere of mechanical transport first made acquaintance with this form of getting about.

Soon after learning all I could about this Douglas I became the owner of my own machine, a Rudge Multi, looked upon in those days as something very hot indeed. It had a single-cylinder engine, belt drive, and a complicated arrangement whereby moving a lever altered the position of the back-wheel driving sprocket and so altered the gear ratio. The result was that with this device you had a very wide variety of gear ratios, with the option of a high top gear for fast cruising.

A variety of machines followed. Another Rudge, then a Velocette two-stroke, two Nortons, a Rex and an Indian, some of which were certainly very fast. This was in the days soon after the war and when I had just left Tonbridge school and was enjoying the cultural ministrations of a gentleman known as a ‘crammer’ – most of us have to undergo examinations at one time or another!

In 1923 I achieved an ambition and raced at Brooklands, and won my first race – a standing start lap at no less than 54mph. I rode Nortons in 1924 and in that year I joined the RAF. During this time I was stationed in Cheshire and raced consistently at Brooklands.  Soon after this I began to ride machines for my friend, RM ‘Nigel’ Spring, and we had rather a successful time in the 500cc and 750cc classes, including the breaking of several records.

In 1924 I had the good fortune to win four races in one afternoon at Brooklands, which naturally filled me with great glee. In 1925 that great wizard of motorcycle racing, the late Bert LeVack, offered me his 1000cc Brough Superior to ride in the 200 miles race, which excited me quite a lot, as this was without a doubt a very fast machine. In the race, however, things did not order themselves too well, and I had a good deal of bother with the tyres and carburetion, so that I met with no noticeable success. However, to make up for this, I won the 200 Miles Sidecar Race, and a few other races fell to me, plus a few records later in the year.

Up to this time I had always looked down on the motorcar racing game but I very much admired a Bugatti of George Duller’s, and in 1926 I acquired a 2-liter straight-eight Bugatti of my own, the second of the type imported into this country. With this car I had a shot at car racing at Brooklands and met with a measure of success. Since then I have raced motorcycles (not so much on the two-wheelers this last year or so, for various reasons) and all sorts and shapes and sizes of racing cars.

As you may know I was a member of the Schneider Trophy team in 1928-29, and then, leaving the Royal Air Force, I became test pilot for the Fairey Aviation Company, the famous aircraft concern.

Although naturally there are similarities, motorcycle and car racing are not very much alike, and of the two, car racing is, I think, the more difficult and, if anything, the more dangerous. Motorcycles seem to steer better than the cars, and in an accident the rider is usually flung clear, which is a great safety factor. Cars are, of course, much faster than the two-wheelers, but the latter form a magnificent training school for car racing. Many of the best racing-car drivers began as motor cyclists – the late Bernd Rosemeyer, Tazio Nuvolari [read about Nuvo’s motorcycle racing here – ed.], Achille Varzi, and in this country, Freddie Dixon, are examples.

In both forms of sport there is the same need for perfect judgement of speed, the same gentle touch for braking and the same benefits from experience. A motorcycle has to be ridden – there is no question of a machine keeping itself up owing to its speed. Riding a motorcycle at great speed calls for the utmost physical fitness. When you see a motor cyclist flying down a bumpy road at over 100mph it keeps upright by reason of the skill, courage, and experience of the rider and for no other reason.

Both in car racing and motorcycle racing a sense of balance is necessary, for in a car entering a corner, the driver must feel the slightest tendency of the car to slide – which is a sense of balance. In both forms of sport there is a need for the right touch on the controls, gentle when needed, and at times brutal. On the whole I think a car calls for more physical strength, both on a twisty road circuit and at high speed on the outer Circuit at Brooklands. In both forms of racing there is the same matching of hand and eye, the same judgement of distances for braking and of speeds for cornering, the same ear for the engine note and the same careful nursing of the machine. It it a poor driver who bursts his car by overdriving.

The fastest cars are faster than the best motorcycles. The power to weight ratio is about the same in both, but the car has better streamlining. A road-racing motorcycle will weigh about 350lb and will develop about 50 brake horse-power. A Grand Prix car of the 1937 type weighed about 18cwt and gave off about 500bhp. The car has better road holding, better suspension, better braking and greater inherent stability, which all tends to make the car faster on the road. On road circuits where cars and motorcycles both race at various times, the cars have proved the faster, by as much as 10mph on the lap speed.

As to acceleration, I suppose the motorcycle is faster off the mark and faster for perhaps the first 100 yards, but when a Grand Prix car has overcome initial wheelspin and inertia, its accelerations is better than that of the two-wheeler.

The motorcycle record for the standing start kilometre is 98.9mph whereas the car record for this distance is 117.3mph [this is 1938… ed.].

Racing motorcycles will develop as much as 120 or 150 horse-power per 1000cc of engine size, but the latest Grand Prix cars will exceed this. Most racing cars have supercharged engines, producing astonishing power from small units by this means, but supercharging has not yet caught on in the motorcycle world owing to special problems of carburetion, added to which although a supercharger can be mounted on a motorcycle quite neatly, it absorbs some power in the drive and the extra power produced seems offset by the power used up in the driving.

The carburetion problems of aircraft are far more complex than either in a car or a motorcycle. A car operates always at about the same barometric pressure, so that carburetors can be tuned with precision for every given racing circuit and left at that for the race. An aeroplane needs carburation for varying barometric pressures and for varying temperatures according to the height at which the aeroplane is flying, added to which the carburetion must be right for all weathers, including frosty conditions. An aeroplane starts off from sea level and is called upon for maximum speed at say, 20,000ft, where the weight of air drawn into the cylinders is far less than on the ground. Every tourist knows how his motor car loses power in climbing a high Alpine pass of perhaps 6000ft, owing to the fall in barometric pressure which allows the mixture to become too rich. An aeroplane at 20,000ft would in the same way have a hopelessly over-rich mixture and would lose a great deal of power at what is its usual service altitude.

To counteract this, supercharging is used, but on a more complicated system than in a racing car. Various forms of supercharger control are used, but in all the idea is to give a constant boot pressure at all altitudes. Some use a completely automatic device, rather like a throttle governor operated by a barometer which opens the throttle as the machine climbs higher; other have the same plus an ‘override’ to give extra boost for take-off only. The Rolls-Royce Merlin engine is a good example of the completely automatic type: the supercharger give plus 6lb boost at ground level and at all heights. At ground level the engine runs on a restricted throttle opening, which gradually opens to full throttle at a given height, the supercharger giving its plus 6lb boost all the time up to this height.

Aero engines resemble car engines in all essentials, but are much more expensively made, with the finest procurable materials, the best labour and with exhaustive tests, which all send up the price. A racing car engine is tuned much nearer to breaking point than an aero engine, and after one race has lost its fine edge of tune and has to be inspected and perhaps reconditioned. Thus after a Grand Prix, the German cars are sent back to the works for inspection and re-tuning, while a different team of cars is sent out to the next race. An aero engine, on the other hand, must be capable of giving off its full power for very long periods with only routine maintenance – checking of valve clearances, plugs, filters, and so forth.

In road racing the car engine never runs at full throttle for more than a few minutes at the outside – the life of such an engine at full throttle is very short. A Grand Prix engine will give about 500bhp for a matter of a few hours, after which, unless the throttle were closed down, there would be a loud bang in the works. An aero engine must be capable of passing the Air Ministry Type Test which is 100hours on nearly full throttle, and must give off power corresponding to the machine’s cruising speed – ie maximum safe revs – indefinitely (about three-quarter throttle). Reliability is good to have in a car – but is essential in aircraft.

Speed on two wheels feels colossal. A car feels slower at 100mph than a motor-bicycle at that speed owing to the rider of the latter being exposed to the wind and being much closer to the ground flashing away under him.

But 100mph in a car feels far more exciting than an aeroplane at 300mph – and many RAF aeroplanes will do far more than that flying straight and level. It is extraordinary how, after flying at high speed and the pilot comes in to land at 80mph, the machine appears to be crawling. Reduction from high speed to low velocities is always deceptive, as one mechanic found out at Brooklands when his driver slowed down to 30mph and the unfortunate man stepped out under the firm impression that the car had nearly stopped.