It happened during the spring of 1914, at one of the famous Hendon Saturday afternoons. A very strong, gusty wind was blowing… The first machine to be brought out was an 80 h.p. Morane monoplane piloted by Philippe Marty, a Frenchman, who asked me whether I would like to accompany him as his passenger. With the enthusiasm of youth, I agreed to do so.
Marty taxied out to the far side of the aerodrome in order to take off into the wind; but the machine left the ground all too quickly, with the result that a strong gust lifted us up about forty feet in the air and then left us in a stalled attitude, with practically no forward speed. The machine staggered for an ominous moment and then stalled.
I have never forgotten the horrible sensations of the next few seconds, and I don’t suppose I ever shall. The left wing seemed to drop out of sight, and I saw the right wing sweep round the sky above us like a sort of windmill vane. Then the roar of the engine stopped.
I thanked heaven that Marty had switched off in time, for a second later the Morane’s nose hit the ground with a bang and a crash, just as she had settled into the position of a vertical nose-dive. As she cartwheeled over on to her back I ducked well down inside the fuselage, and there we were – upside down, unable to move an inch and fairly soaked with petrol from the burst tank.
Meanwhile the aerodrome staff had hastened to the scene of disaster. When the machine’s tail was lifted up we both fell out of the fuselage, whereupon all our rescuers began to laugh. This only sent Marty off into spasms of mirth-provoking Anglo-French fury. All of which may have conveyed the impression that we were rather a heartless set of fellows, but although a pilot who was hurt in a crash came in for his due share of sympathy, it was the custom at Hendon to give him a dose of ridicule if he was fortunate enough to escape injury.20
This vignette of a typical flying accident a few months before the First World War is revealing on several counts, apart from acting as a reminder that even today, a century later, a stall on take-off still causes multiple fatalities each year around the world, especially in light aircraft like this. At the time it was a familiar occurrence and the writer, Louis Strange, was very lucky. Many such crashes caught fire and their trapped survivors, often still very much alive and all too audible, were burned to death in front of the horrified spectators and ground crews. Aviation spirit, together with the aircraft’s wooden construction covered in doped fabric, could produce a raging bonfire within seconds. Despite the rapid developments in aircraft design that the war was to expedite, flying remained a high-risk pastime for many years, as the aeronautical engineer and future popular novelist Nevil Shute was to discover when working for the de Havilland company in the 1920s.
The jocular phrase that one was going out to flirt with death was not entirely jocular in 1923. Humour was grim at times on Stag Lane Aerodrome. There was a crash wagon with fire extinguishers on it ready at all times when flying was in progress, as is usual, and this crash wagon was provided with a steel rod about eighteen feet long with a large, sharpened hook at one end. This was for the purpose of hooking the body of the pilot out of the burning wreckage when the flames were too fierce to permit any gentler method of rescue. It was the custom at Stag Lane when a pupil was to do a first solo to get out this hook, to show him that his friends had it ready…21
As it turned out, Louis Strange’s luck went on holding to a phenomenal extent (as will shortly become even more apparent). He was the pilot mentioned in the previous chapter who had flown the first F.E.2b out to France and he was to have a most distinguished war, emerging practically unscathed from his years as a combat pilot and flying instructor, neither of which profession was noted for longevity. His pilot that day at Hendon, Philippe Marty, was not so lucky. He was to die only a few weeks later from stalling his machine once again, this time at 200 feet.
The story shows vividly how very susceptible early aircraft could be to chance gusts of wind. This was because they were of the lightest possible construction, which in turn was the result of the aero engines of the day being generally weak. This further restricted what could be achieved by designers’ limited understanding of aerodynamics. Among the earliest pioneers the Wright brothers in America were the most consistently scientific and systematic in their approach to flight, and this undoubtedly formed the bedrock of their success. Not only did they build a primitive wind tunnel to test their wing shapes, they also designed the first true aero propeller. Various propellers had already been tried on dirigibles, but they were mostly based on ships’ screws and even on paddles. It was the Wright brothers who broke decisively with the nautical model and reasoned that a propeller blade was in effect a little narrow wing that needed to be given a twist to ensure it created more lift than drag along its entire length as it revolved. Since the engine was mounted horizontally this lift simply became thrust. The propellers they crafted out of wood for their ‘Flyer’ were a mere 4 or 5 per cent less efficient than are the best computer-designed propellers well over a century later. It was a stroke of engineering genius for two men calculating with paper and pencil in a bicycle workshop.
Besides adequate thrust, powered flight depended on the aircraft being controllable. The Wrights and the German pioneer of man-carrying kites, Otto Lilienthal, are between them credited with having worked out the basic principles of aerodynamics and control. However, as the Wright brothers themselves acknowledged, credit for that actually belonged to an extraordinary Englishman, George Cayley, who was born in 1773. He was the first person known to have worked out that the four main forces acting on any aircraft as pairs of opposites are gravity and lift, thrust and drag. He also designed the first cambered wing for generating lift; this became the standard aircraft wing shape such as the Wrights tested in their wind tunnel and which has persisted to the present day. Cayley first constructed and flew a model glider as early as 1804, and in 1853 an employee of his bravely made the first manned glider flight in one of Cayley’s designs at Brompton Dale in Yorkshire, nearly half a century before Lilienthal’s experiments with what were essentially the first hang-gliders. Modern replicas of Cayley’s glider have since been flown successfully in Britain and America to prove that, primitive or not, it really had worked.
As the Wrights and their contemporaries in Europe had learned from their kite-building, there are three basic axes in flight: roll, yaw and pitch. Roll is when an aircraft tilts or banks to one side or the other; yaw is when the tail swings from side to side like oversteer in a car; and pitch is its nose-up or nose-down attitude: climbing or diving. To steer their ‘Flyer’ by using yaw, the Wrights employed the same vertical rudder that they and others had used for their gliders, although they mounted this at the front, canard-style, rather than at the back. To achieve both pitch and roll they devised a system of wing warping, or bending the entire wing. This device was still used extensively on early aircraft like the Morane-Saulnier GB type in which Marty and Strange stalled and crashed at Hendon in 1914, although by then the method was obsolescent: a process that the Wrights themselves had unintentionally hastened.
For, in the wake of their epoch-making success of late 1903, the brothers made an error of judgement that was to cost America the lead in aviation and cede it to Europe. This was to take out a patent on their aircraft’s control system and then to become litigious. It was not only their own wing-warping they patented but any form of flight control that involved interfering with the airflow over the outer portions of a wing. Their lawyer was quick to bring legal actions against aspiring rivals in the United States and even against visiting aviators from Europe who experimented with any form of wing-bending to control their own aircraft. This was vociferously condemned as selfishly hindering progress, especially in Europe, where no pioneer was about to quit his own researches out of respect for an American patent. This attempt to monopolise the science of controlling an aircraft backfired even in the United States itself where another great figure of early aviation, Glenn Curtiss, was harried by the Wrights’ lawyer. The mantle of leadership effectively passed across the Atlantic to men like France’s Voisin brothers (who had opened their first aircraft factory as early as 1904), the Farman brothers, Armand Deperdussin and Louis Blériot. Other European pioneers included the young Dutchman Anthony Fokker and in Britain the American Samuel Cody, the Irishman J. W. Dunne, A. V. Roe, Geoffrey de Havilland and Claude Grahame-White. In the United States it was a measure of Glenn Curtiss’s brilliance and determination that despite the Wrights’ opposition he still managed to produce original and sound early aircraft as well as founding one of the great American aircraft companies. Generally speaking, however, after its pioneering start in aviation the United States rested on its laurels to such an extent that when it finally went to war on the Entente (Allied) side in 1917 American pilots were obliged to fight in French and British combat aircraft, with the honourable exception of a few Curtiss HS-2L flying boats that performed long-range escort duties for cargo ships running the gauntlet of German submarines.
British aviation owes a very large debt to Samuel Cody who, as mentioned in the previous chapter, was the first to achieve powered flight in Britain. Calling himself Colonel Cody, he was a barely literate Texan showman with a twelve-inch moustache. At the turn of the twentieth century he was touring British music halls giving ‘Wild West’ exhibitions of trick shooting and riding. But what really fascinated him was flying, and he devised a series of man-lifting box kites for military observation. These duly caught the eye of both the British Army and the Royal Navy and by 1906 Cody found himself at the Army’s Balloon Section at Farnborough. His problem was money, since at the time the military were still only interested in balloons and could see no future in the powered aircraft he wanted to build. In the teeth of opposition, by one means or another (and mainly by sheer force of ebullient charm) he managed to put together something he called the ‘British Army Aeroplane No. 1’, and on 16th October 1908 he flew it. Like most of the pioneers he had taught himself to fly and had no formal education in aircraft design. Carpers accused him of having cribbed his machine from his fellow American, Glenn Curtiss, but by now there were aeronautical inventors in most European countries, travelling around to displays, swapping information, accusing one other of plagiarism and promoting their own designs while learning from each other. Nevertheless, at Farnborough Cody was often ridiculed as ‘the Texan showman’ and ‘the cowpuncher’ for being no scientist and generally self-taught.
In 1913 the Daily Mail offered a prize of £5,000 for the first person to fly a ‘waterplane’ around Britain, including a flight across the Irish Sea to Dublin. Cody, by then aged fifty-three, built a new aircraft of his own to meet this challenge. It was his sixth design: a biplane so large it was mocked at Farnborough as ‘Cody’s Cathedral’. The young Geoffrey de Havilland, who as well as being a pilot had formally studied aircraft design, infuriated Cody by sauntering over to his immense machine, plucking its flying wires like harp strings and telling the old showman that he really needed to double them for added strength. Cody assured this whippersnapper that it was as strong as a house. On 7th August, the day Cody was due to fly his ‘Cathedral’ down to Calshot to have its floats fitted for the competition, he decided to give two friends the flights he had long promised them. On the second of these he took up W. H. B. Evans, the captain of the Hampshire cricket team.
Two of Cody’s three sons, Leon and Frank, were among those watching as Cody circled the clubhouse of Bramshot golf course and turned back towards Laffan’s Plain. They saw the plane stagger and the wings fold upwards. Cody, easily identified by his white coat and cap, followed by his passenger, were catapulted from their seats at a height of between 300 and 500 feet. Their bodies, followed by the wreckage of the plane, fell into a clump of oak trees 50 yards apart. Cody’s publicly expressed wish that, when it came, death would be ‘sharp and sudden, from my own aeroplane, like poor Rolls’, had been granted.22
‘Poor Rolls’ was the Hon. Charles Stuart Rolls, who had gone into partnership with Henry Royce in December 1904. On 12th July 1910 Rolls was piloting a Wright ‘Flyer’ at Bournemouth when its tail broke off and he was killed, the first person in England to die while flying a powered aircraft. As for Cody, the Daily Mail gave him an epitaph on 11th August in the form of a bitter poem by a certain J. Poulson.
Crank of the crankiest, ridiculed, sneered at,
Son of a boisterous, picturesque race.
Butt for the ignorant, shoulder-shrugged, jeered at,
Flint-hard of purpose, smiling of face.
Slogging along on the little-trod paths of life;
Cowboy, and trick-shot, and airman in turn.
Recklessly straining the quick-snapping laths of life,
Eager its utmost resistance to learn.
Honour him now, all ye dwarfs who belittled him,
Now, ’tis writ large what in visions he read.
Lay a white wreath where your ridicule killed him;
Honour him, now he’s successful – and dead.
As a sacrificial victim of early aviation Sam Cody was hardly alone. He had his counterparts all over Europe and elsewhere: men with a mechanical bent who for ten years had been putting together flying machines of their own design in sheds and garages, each convinced that his would prove revolutionary, only for the dream to end in a tangle of wire and fabric in the middle of rough pastureland. ‘The only bones left unbroken in the cadaver,’ as one army medic bleakly observed, ‘were probably those of the inner ear.’
The single flight that first made it clear aviation was a practical mode of transport and not just a spectacular way of getting killed was Louis Blériot’s across the English Channel on 25th July 1909. His model XI was the world’s first powered and truly airworthy monoplane and it was to inspire several other similar designs, including those by Morane and Fokker. Blériot’s soon became the world’s most-produced aircraft, being bought by flying schools and several European countries for evaluation of its military potential. Indeed, it was Anthony Fokker’s derivation of it, the Fokker E.1 Eindecker (monoplane), that was to establish temporary German air superiority in the skies above France and Belgium in 1915. Yet by then early monoplane design was revealing its limitations. With the exception of the E.1’s forward-firing machine gun the aircraft itself was rather old hat and could be outperformed by several biplanes at the time.
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This prompts a question. Why was it – to judge from contemporary photographs and films and all the popular imagery of the first air war – that the vast majority of aircraft in those days were biplanes and even triplanes? Only part of the answer is that four wings produce more lift than two. Four wings can also be made much stronger, the struts and wires between the pairs producing the effect of box girder construction. A box girder resists torsion, or twisting; and twisting was the inherent problem of the wood-framed wings of the day. Because Blériot, Fokker and many others at first used Wright-style wing warping to control their monoplanes’ pitch and roll, the wings had to be able to twist. But as speeds increased, together with a need for more manoeuvrability, so much torsion could be set up that the wing could be torn entirely off. Aircraft shedding their wings as Cody’s ‘Cathedral’ had were a distressingly familiar sight at air shows and also accounted for a good many deaths in Fokker’s and other monoplanes of the period. Blériot’s famous model XI was similarly plagued by structural failure and earned itself the nickname of ‘The Killer’. It was obvious that as a method of control, wing warping was doomed. Quite apart from anything else, it was mechanically complex. As Fokker himself later admitted of his own aircraft, ‘To warp the wings for elevator action required twelve wires, running on rollers and centring on the control stick. This was bad mechanics, however good a theory it might be.’23 The wings of a biplane, on the other hand, could be made remarkably stiff when built as a box girder, and pitch and roll could then be achieved by the far simpler method of ailerons: hinged flaps on the trailing edges at the ends of the wings. In this way pairs of stiff wings equipped with simple ailerons revolutionised control and effectively became the basic design for most of the aircraft that flew in the First World War.
However, designers soon found that doubling the number of wings did not double the lift. The reason for this is inherent in the way a wing works. Its cambered shape produces a drop in pressure in the airflow as it passes over its curved upper surface, creating a vacuum effect that ‘sucks’ the wing upwards. At the same time the flatter underside of the wing, at an angle to the airflow (the ‘angle of attack’), produces an increase in pressure that ‘pushes’ the wing upwards. Both these forces together produce lift. In a biplane, though, with one wing above the other, there is interference between the positive pressure beneath the upper wing and the negative pressure above the lower, cancelling some of the potential lift. It was for this reason that, as the war went on, aircraft designers tried either increasing the distance between the top and bottom wings or else ‘staggering’ them so they were not directly above each other. Usually the top pair was placed slightly ahead of the bottom pair.
It was soon discovered that, with careful placing of a biplane’s centre of gravity and by not designing it for stability at all costs, it could be made much more agile if often trickier to fly. This might be achieved by ‘short-coupling’: reducing the length of the fuselage so the aircraft became stumpier. There were subtleties of fine-tuning, too. The diagonal wires between the pairs of wings could be tightened or slackened by means of turnbuckles. By careful alignment of the tail with the centre section (the roofed ‘box’ of struts that surrounds the cockpit), the aircraft could be deliberately trimmed to fly in a particular way. ‘Tuning’ a biplane to suit its pilot became a valued skill on the part of his rigger mechanics.
Sundry variations in design were tried during the war, including that of adding a third pair of wings. The first triplanes to be seen were the big Voisin bombers of 1915 and 1916, when a third wing was very obviously a load-bearing measure. When Britain’s Sopwith company came up with the first little triplane fighter in 1916 it seemed revolutionary. It was found that three pairs of somewhat shorter wings could confer amazing agility in the air and the design of the ‘Tripe’ was quickly copied. As mentioned earlier, a plethora of different triplanes came from Austro-German manufacturers, most notably Fokker’s Dr.I which today is most associated with Baron von Richthofen. Yet the triplane craze was short-lived. While increasing the number of wings can indeed increase lift, it also adds weight and drag. The Dr.I was noticeably slower than many of its contemporaries and although initially it climbed well it soon became sluggish at altitude.
The French company Nieuport, which built some of the war’s most successful fighters, went in another direction, that of the sesquiplane. This literally means ‘a wing and a half’, and the Nieuport design was a biplane in which the lower two wings were much narrower and shorter than the upper. They were pretty machines and generally very agile. The flying aces Eddie Rickenbacker, ‘Billy’ Bishop, Albert Ball and Charles Nungesser all flew Nieuports for preference at one time or another. They liked their manoeuvrability and responsiveness to the controls. But even they needed to be careful not to over-stress the aircraft because the narrow lower wings suffered from the same old problem that monoplanes had: they couldn’t be built rigid enough to withstand too much torsion, and the twisting forces sometimes caused the wing to fail, which usually led to the break-up in mid-air of the entire machine.
The generic problem with biplanes of all kinds was always going to be that of drag, which in turn would limit speed and demand ever more power to overcome it. Biplanes needed struts and wires between the wings, and it hardly helped that they also had fixed undercarriages, a further potent source of drag. There was simply a mass of stuff obstructing the airflow and contributing nothing in the way of lift. In the earlier part of the war aircraft were practically always of all-wood construction, although as engines became more powerful and weight a little less critical metal began to be used for certain parts of the airframe. It was all a matter of weight and the availability of materials. Aerodynamicists realised that in the end the only way to make an aircraft fly faster was to reduce drag and go back to monoplane design; but the problem remained of how to make a cantilever wing stiff enough to withstand the twisting and flexing forces of high-speed manoeuvres. Wood and contemporary glues lacked strength. Making main spars of steel would be too heavy. What was needed were light alloys, but the sort of metallurgical research needed to develop and test them was very time-consuming and besides, even if the ideal metal – both strong and light – were found, the uncertainties of wartime supply made it unlikely that any sort of mass production could be reliably undertaken. At the same time aviation-quality seasoned wood of all kinds became progressively scarcer as the war went on and frames of steel tubing and even monocoque (stressed metal skin) construction were introduced here and there before the war’s end, most notably by German companies like Junkers. It is a measure of the difficulties that only in the early 1930s did all-metal structures slowly become the norm for larger aircraft, while military biplanes persisted here and there even into the Second World War (the Gloster Gladiators that defended Malta in 1940, for example). These late biplanes now had metal frames even if their flying surfaces were still partially covered with fabric. Debatably the most impressive, as well as the fastest, biplane fighter of all time was the Italian Fiat CR.42 ‘Falco’ that flew in numbers in several theatres in the Second World War. It was actually a sesquiplane, its lower wings being much shorter than the upper. Yet although outstandingly manoeuvrable and quick, it was ultimately no match for that war’s potent all-metal monoplane fighters. Even so, wood continued to be used to advantage in certain airframes, most notably in the Hawker Hurricane and the de Havilland Mosquito.
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Manoeuvrability was always going to be a critical factor in aircraft and its development was much accelerated by the requirements of war flying. For some time, though, what pilots could do in the air was limited not merely by their machines’ structural weakness but by an incomplete understanding of aerodynamics. In addition, the conservative way in which pilots were trained deterred them from performing certain evolutions. By 1914 rolling, diving and even looping an aircraft were all crowd-drawing novelties at any air show, thrilling spectators with both the spectacle and the likelihood of disaster. However, at that time the RFC actively discouraged such ‘stunting’ by its own pilots as being no better than vulgar showing-off. This revealed how very far the British Army still was from recognising the need for pilots skilful enough to fight rather than just to act as chauffeurs for their observers. For at least the first two years of the war stalling and spinning remained aviation’s great bugbears, to be avoided at all cost. In particular, spinning was a phenomenon that scared pilots everywhere simply because nobody really understood its cause, still less how to stop it and regain control.
It was recognised that the main way to trigger a spin was by losing flying speed. The stall at Hendon that Louis Strange survived showed classic symptoms, and had it occurred at a higher altitude – say 500 feet – the Morane would undoubtedly have spun into the ground. Strange’s observation that the aircraft gave a ‘stagger’ is an exact description of the buffeting that occurs at stalling point. In his case the Morane’s left wing stalled first, losing all lift and gaining drag, while the right wing maintained lift and so swung up and around. Luckily for Strange and Marty they were still low and impact with the ground prevented this from developing into a full autorotation that the pilot appears helpless to stop. Several showmen of the day claimed to be able to spin at will, but there is no reliable evidence for this. What they were probably doing was known then as a ‘tourbillon’ spin: essentially a tight downward spiral as opposed to autorotation. In other words they were maintaining airspeed and were under control, effectively rolling the aircraft but vertically downwards instead of horizontally. All they had to worry about was being able to pull out high enough above the ground without their wings folding up under the strain. A genuine spin was a very different matter and for a while it was nearly always fatal.
At six in the morning of 25th August 1912 a young naval lieutenant, Wilfred Parke, and his RFC observer took off from the Army’s Larkhill aerodrome on Salisbury Plain in an Avro biplane for a three-hour qualifying flight. They returned to the airfield at nine o’clock at an altitude of around 700 feet and Parke banked the machine to lose height in order to land. Thinking his angle of descent too steep, he pulled back on the control wheel and the machine immediately stalled and whipped into a left-handed spin. The technical editor of Flight described it for the magazine’s next issue:
[T]he machine was completely out of control, diving headlong at such a steep angle that all the spectators described it as vertical and stood, horror-stricken, waiting for the end. According to Parke the angle was very steep, but certainly not vertical; he noticed no particular strain on his legs, with which he still kept the rudder about half over to the left (about as much as is ordinarily used in a turn), nor on his chest, across which a wide belt strapped him to his seat. His right hand he had already removed from the control wheel in order to steady himself by grasping an upright body strut… This he did, not for support against the steepness of the descent but because he felt himself being thrown outwards by the spiral motion of the machine, which he describes as ‘violent’. It was his recognition of the predominating influence of the spiral motion, as distinct from the dive, that caused him to ease off the rudder and finally push it hard over to the right (i.e. to turn the machine outwards from the circle), as a last resort when about 50 feet from the ground.
Instantly, but without any jerkiness, the machine straightened and flattened out – came at once under control and, without sinking appreciably, flew off in a perfect attitude, made a circuit of the sheds, and alighted in the usual way without the least mishap.24
This incident became famous in aviation circles as ‘Parke’s Dive’, and remains the first known detailed description of an aviator surviving an unintentional spin. It so happened that the Royal Aircraft Factory at Farnborough had recently been asked to investigate the phenomenon of spinning and by good fortune the young Geoffrey de Havilland was present at Larkhill that day as their representative. He promptly debriefed Lieutenant Parke at length in the mess. It seems unlikely that Parke would have had much of an appetite for breakfast and his observer – who had worn no seatbelt and had been pinned helplessly to the side of the aircraft by centrifugal force – still less. But de Havilland, self-taught pilot that he was, must have clearly noted the lesson of Parke’s Dive because at some date in 1914 he deliberately spun an aircraft knowing how to regain control.
Dunstan Hadley, a Fleet Air Arm pilot who flew Fairey Barracuda torpedo-bombers in WW2, made a particular study of the history of spinning and consulted records in the USA, France, Italy and Germany as well as in the UK. He concluded that Geoffrey de Havilland was ‘the first British pilot to have spun intentionally, knowing he could recover; and until any earlier claim is discovered and verified, it stands as both the British and world record for the earliest known deliberate spin’.25 As for Lieutenant Parke, he had just under four more months to live, being killed while flying a Handley Page Type F monoplane when it suffered engine failure on a flight from Hendon to Oxford in December 1912. He was twenty-three.
Thereafter, one would have thought the method for getting out of a spin would have spread like wildfire throughout the flying fraternity – reduced to a life-saving mantra such as Full opposite rudder, stick centred, throttle back or, a little later, Throttle back, stick forward, pause, opposite rudder. Yet the mere fact that spins were still almost superstitiously feared four or five years later shows it did not. Even a pilot as accomplished as Cecil Lewis was clear on that point:
In 1916, to spin was a highly dangerous manoeuvre. A few experts did it. Rumour had it that once in a spin you could never get out again. Some machines would spin easier to the left than to the right; but a spin in either direction was liable to end fatally. The expression ‘in a flat spin’, invented in those days, denoted that whoever was in it had reached the absolute limit of anger, nerves, fright, or whatever it might be. So spinning was the one thing the young pilot fought shy of…26
Even so, 1916 was also the year Major Lanoe Hawker, VC, put his DH.2 through a series of spins above his squadron’s airfield to demonstrate to his assembled pilots that this aircraft’s reputation for fatal spinning was unwarranted, and that it was perfectly possible to spin it deliberately and regain control.
Part of the reason for this fear must also have been that for many pilots the remedy for a spin was counter-intuitive. One instinctive reaction was to freeze and steer into the spin, as though to mollify the machine by going along with it before finding a way of coaxing it out of its disorder. Yet any horseman would know that was fatal. It required a masterful hauling of the beast’s head round, using strength. Full opposite rudder. Also, if you were heading for the ground out of control, the last thing you felt like doing was pushing the stick forward. Yet the chances were the stall occurred in the first place because you had the stick back and had lost flying speed. It was soon learned that each aircraft, as well as every type, could have slightly different stall and spin characteristics. Even so, it would not be until 1925 that the RAF made it mandatory for a company’s test pilots to complete spinning tests on any new aircraft before it was accepted for trials by the RAF’s own test pilots.
As combat became more aerobatic during the war, the more adventurous pilots did learn to spin at will, knowing they could recover, and it became a trick used to simulate being shot down in order to fool an opponent. Yet by no means every pilot either mastered it or wished to try. Spinning in general went on having a bad reputation, while particular aircraft became notorious for it. A centre of gravity too far aft was always a danger sign. An additional problem was that the slightest alteration to the airframe – putting on an external mount for a camera or adding a fairing behind the pilot’s head – could sometimes drastically change an aircraft’s spin characteristics and a new set of trials would be needed. As Dunstan Hadley observed, ‘Even by the 1930s the dynamics of the spin were imperfectly understood and trial and error was very much the order of the day.’ It should be added that much the same applied to the stall, which continues to be a problem to this day, as witness several recent accidents to commercial airliners involving the loss of all on board. Any complacency in flying of any kind sooner or later proves fatal, as does putting too much faith in training pilots entirely in simulators in order to save money. There is no substitute for live cockpit experience, preferably including a couple of hundred hours in light aircraft or gliders.
Quite apart from pilot training, though, it should be remembered that every light aircraft has a personality of its own: not just the different types but each individual machine. It can differ in ways no rigger or fitter or mechanic can account for, acquiring a reputation for docility or sluggishness, the engine not giving full revs in a steep turn or overheating, even occasionally making a mysterious faint whinnying sound like a pained horse. Some aircraft feel eager to fly as soon as the engine starts, others much less so. It can’t be explained. (Many drivers feel the same way about cars.) This was especially true in the First World War when so much production was farmed out to various factories, each of which had slightly differing work practices according to what they had been making before the Munitions of War Act obliged them to build aircraft. The machines they turned out may have looked identical – may have been identical in the sense of meeting specifications – but they seldom flew identically.
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In many ways it was the engine as much as a growing understanding of the basics of flight that determined the progress of early aviation. Weight was absolutely critical, and power-to-weight became a ratio that haunted every aircraft designer. It can be argued that an equal hero of the Wright brothers’ first controlled and powered flights was their mechanic, Charlie Taylor, who was asked to provide an engine for what was essentially one of the Wrights’ manned gliders. In the absence of any existing engine light enough to power an aircraft weighing only 604 lb, Taylor built a 12 h.p., four-cylinder inline engine whose block was cast aluminium. He did it from scratch in six weeks and the resulting engine weighed a mere 180 lb. For its time it was a masterpiece of off-the-cuff engineering.
On the other hand, it was weak. French aviation pioneers like the Voisin brothers were not satisfied with the Wrights’ top airspeed of 30 mph in 1904. This was, after all, the year Henry Ford set a new land speed record of 91 mph. They turned to the rotary engine. This was originally a French invention, although by the turn of the twentieth century it had been developed elsewhere, notably in the United States for use in cars. Now the three Voisin brothers set up a rotary aero-engine business called Gnome, which along with Le Rhône and Clerget was to become a major engine supplier to the Allies during the war. Many companies also made Gnome rotaries under licence, especially in Germany. Trade was trade, even in wartime.
Rotary engines look like radial engines in that both have their cylinders arranged as a ‘clock face’, but they function quite differently. A radial engine, like a car engine, is stationary and turns a crankshaft in the normal fashion, whereas the rotary’s crankshaft is fixed and the entire block of cylinders turns around it. If it is to be used in an aircraft, a propeller is simply bolted to the front of the rotating engine. By modern standards this may seem a bizarre arrangement but in the early days of aviation it offered important advantages over a conventional stationary engine, the main one being that it had an impressive power-to-weight ratio since it was very light. As the cylinders whirled around they cooled themselves in the air and there was therefore no need for a bulky system of radiators and water jackets. Secondly, a rotary engine ran very smoothly because the whole thing acted as a flywheel. And thirdly, it was extremely compact, amounting to little more than the clock-face of cylinders with its circular sump in the middle, like a fat hub surrounded by spokes. This compactness was a useful feature, and in a fighter like the Sopwith Camel it meant that the first seven feet of airframe could accommodate the entire ‘works’: engine, fuel tank, guns and pilot. This design led directly to that fighter’s hair-trigger handling which was to gain it so many combat victories.
But back in the summer of 1914 it is practically certain that not a single British military aircraft that flew in the first batch to France had a British engine. Initially, our development of both aero engines and aircraft was seriously hampered by a chronic lack of machine tools, ball bearings and magnetos, as well as steel and alloys of sufficient quality. Britain, the erstwhile cradle of the Industrial Revolution, now had only a single ball bearing factory capable of bulk output and supplies had to be imported urgently from Sweden and the United States. As for magnetos, home-grown production proved equally inadequate and until mid-1916 the RFC relied largely on a pre-war stockpile of German-made magnetos to enable its aircraft to fight Germany.27 By 1918 the desperate modernization of British industry had gathered considerable pace and things had much improved. Even research into new alloys had become advanced.
For the first two years of the war, however, the RFC was almost entirely reliant on French-designed rotary engines. In fact, in August 1914 there were only two British-designed aero engines being built, the 60 h.p. Wolseley that powered the earliest B.E.1 and Sunbeam’s 120 h.p. Crusader. Both were V-8s and as such were bulky and heavy for their output. Rotaries were the obvious choice: it was a capable and ingenious design. Tens of thousands were built by all sides throughout the war, and yet they virtually disappeared the moment the Armistice was signed. By then their drawbacks had exceeded their usefulness.
While the rotating engine did indeed provide smoothness, it also produced a powerful gyroscopic effect that could make an aircraft easy to turn in one direction but less so in the other. This feature became notorious in Sopwith Camels, which were typically powered by the 130 h.p. Clerget engine. That aircraft also had a marked tendency to swing on take-off and landing, one of several tricky features that led to countless crashes in training. Because rotaries lacked carburettors they were tricky to control with a throttle. They tended to run ‘full on’, and the normal way to reduce power was by using a cut-out switch that prevented every other cylinder from firing and required repeated ‘blipping’ of the engine. This – together with a fuel-air mixture control that demanded constant monitoring – made flying all rotary-engined aircraft a handful, and the Camel most of all. Rotaries also worked on a ‘lost oil’ principle that used great quantities of castor oil, much of which was sprayed back half-burnt over the pilot.
None of this was ideal, although it had to be lived with at the time. The real reason why the engines fell out of fashion so quickly after the war was because aircraft designers wanted more and more power. Rotaries were comparatively slow-revving and the propeller could only turn as fast as the engine, unlike stationary engines where the power could be greatly increased and the propeller geared for maximum efficiency. (The underlying problem is that petrol engines reach their maximum efficiency at relatively high speeds, whereas propellers are more efficient at lower speeds.) During the First World War rotaries were developed as far as they could be, even acquiring a second bank of cylinders ‘staggered’ with respect to the first. The high point was probably reached with the Bentley BR.2, a magnificent 25-litre rotary engine whose single bank of nine cylinders produced 250 h.p. But rotaries had reached their limit for reasons of simple physics. The faster the cylinders whirled, the more the drag on them increased (since drag in air increases with the square of the velocity). But the power needed to overcome drag is the cube of speed, and very soon a point was reached when much of a rotary engine’s power was spent in making itself turn.
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Given the various armies’ more or less dismissive attitudes to aviation at the outbreak of war, it is ironic how quickly they came to rely on aircraft as engines and airframes improved. It is now possible to view the whole development of aviation during the First World War as a direct consequence of the static trench and artillery warfare on the ground, with rapidly escalating demands for aircraft to fill different and more demanding tactical roles. By early 1915 more accurate anti-aircraft defences were forcing pilots up to 8,000 feet or so, over twice as high as they had been used to flying a mere six months earlier. But at 8,000 feet accurate observation by eye of what was happening within the intricate network of trenches was very difficult, particularly as so much was increasingly disguised from aerial spying by the burgeoning art of camouflage. An observer peering over the side of his cockpit, attempting to stop his goggles being torn off his face in the seventy-mile-an-hour gale while trying to draw maps and take pencil notes on flapping paper with frozen fingers – this was clearly no way to conduct a vital military survey. Thus cameras became more and more important while gaining in intricacy, size and weight, which in turn necessitated better aircraft performance at altitude.
Aeroplanes became increasingly vital for artillery observation, too, which meant it was essential to have quick and accurate communication with the gunners on the ground. No longer could an airborne spotter rely on signalling their hits and misses by shooting off a series of colour-coded flares from his Very pistol. He needed to carry a wireless transmitter, which in turn meant still more weight and improved engine and airframe design to cope with it. In time, aircraft with bombing capabilities were expected to fly to more distant targets with a heavier bomb load, which also meant having to fly higher to avoid anti-aircraft fire. Once aircraft were armed with effective machine guns, observation machines and bombers also needed them for their own defence, as well as increased speed and the ability to climb fast in order to avoid trouble. By the war’s end combat aircraft were regularly reaching 22,000 feet, an unimaginable height only four years earlier.
In this escalating fashion the developing war on the ground fed directly into the way aircraft were built, and it all happened at a breakneck pace. The rival air forces watched each other closely for any new technology, eagerly tore apart their opponents’ latest downed aircraft for its secrets, tried always to keep one step ahead. Serious aeronautical institutions like that at Farnborough did their best to work out the intricacies of flight theory; but in the companies that actually built the aircraft, practice was often more the product of hunches and bright ideas than of theory, and not all the hunches worked. Thus, aviation from 1903 to at least the end of the First World War can be seen as a constant series of experiments as little by little the basics of twentieth-century aerodynamics came together in a solid body of knowledge. The science of flight certainly did not stop there; but a good deal of the raw spadework was achieved in that first air war, albeit at prodigious cost in money and lives.
Many aspects of aircraft design were dictated by factors that had nothing to do with aerodynamics. The sundry French – and particularly British – ‘pusher’ machines were made necessary simply because at the time they had no synchronisation gear allowing a machine gun to fire forward through the propeller arc, therefore the propeller was most easily placed behind. They were not beautiful, those pusher biplanes with a blunt nacelle sticking out in front like a canoe while behind that an open trellis-work of bare metal tubing enclosed a yawning space wide enough to accommodate a whirling eight- or nine-foot diameter propeller. This trellis joined together some fourteen feet behind to support a fabric-covered tail. Pusher aircraft like the D.H.2 were often good for what they were, and usefully manoeuvrable, and at any time other than war they probably offered a pilot the most pleasant flying experience of the day, with all the noise behind him, no prop-wash blowing into his face, and wonderful visibility. But pushers also had inherent disadvantages. One was that any hard object sucked rearwards out of the open cockpit in front – as a pair of goggles or even a pencil might be – could damage or even shatter the propeller. But the chief disadvantage of the pusher type was that the open framework of the ‘fuselage’ caused a good deal of drag that would always put a limit on performance.
Another measure forced upon aircraft designers of the period (not to mention the pilots) was that no ordinary machine had wheel brakes. This was, of course, to save weight; but it did mean that landing in a restricted space could be tricky indeed. Instead, there was a tail-skid (sometimes steerable) that dragged along the ground and slowed the aircraft after landing: always crude but not always effective, especially if the ground was frozen. To limit the run-out trainees were taught to make ‘three-point’ landings: touching down on the main wheels and tail-skid simultaneously. If the machine’s attitude at rest on the ground was at a particularly steep angle, this took practice. The propeller’s size sometimes dictated how a tractor aircraft sat on the ground. A nine-foot propeller at the front of a typically stocky Sopwith design meant the aircraft sat at an angle that left the pilot staring up into the sky. This not only made the view ahead when taxiing almost non-existent without weaving from side to side, but until a pilot got used to it doing a ‘three-pointer’ could go badly wrong.
The same applied to the Royal Aircraft Factory’s generally awful R.E.8, or ‘Harry Tate’ two-seater observation machine. This had been designed to sit with a very nose-high attitude on the ground, not to provide propeller clearance but so that the upward angle of the wings would produce more drag on landing and hence a braking effect when touching down in small fields. It took a lot of getting used to, and no-one was keen to botch a landing in a Harry Tate, an aircraft that already had an evil reputation for catching fire in a crash. (The fuel tank was sited immediately behind the engine, so when – as usual – it split on being forced forward, petrol promptly gushed over the red-hot exhaust manifolds.) Nothing could have made plainer the gulf between the boffins at Farnborough who designed this detail and the wretched men who had to fly the aircraft:
I well remember one very windy day when I had been forced to land on an R.E.8 aerodrome owing to having received a bullet through my petrol tank. Flying conditions were abominable, and I watched four R.E.8s land, all within half an hour. Two pulled up safely, one crashed on landing, and the fourth turned over on the ground. In both latter cases the machines immediately burst into flames, killing pilots and observers. A tribute is due to the squadrons using these machines, and while we scout pilots laughed at them to their faces, behind their backs we heartily respected and admired them.28
On the other hand one Harry Tate became famous as a ‘ghost’ aircraft that never did catch fire. It was doing artillery observation one day in December 1917, flown by two Australians from No. 3 Squadron, Lieutenant J. L. Sandy and his observer, Sergeant H. F. Hughes. Hughes managed to shoot down an Albatros D.Va scout that attacked it and a larger battle ensued when two more R.E.8s from 3 Squadron turned up as well as some more German machines. In the end the Germans broke off the attack and one of the R.E.8s, noting that Sandy and Hughes looked fine, gave a wave and let them get on with their ‘art. obs.’
Somewhat strangely, no further wireless messages were transmitted from Sandy’s R.E.8 and apprehension increased as the evening approached and the aircraft had not returned. To all intents and purposes the aircraft and its crew seemed to have vanished from the face of the Earth. The perplexing mystery was not solved until 24 hours later, when a telegram was received from a hospital at St. Pol, stating that the bodies of Sandy and Hughes had been found in a crashed R.E.8 in a nearby field. It was ascertained that both men had been killed instantly during the aerial combat, when an armour-piercing bullet had passed through the observer’s left lung and thence into the pilot’s head. They had not been injured in the crash-landing, and the R.E.8 itself was only slightly damaged. Apparently, after the crew had been killed, the aircraft had flown itself in wide left-hand circles until the petrol supply ran out. This theory was supported by the fact that a north-easterly wind was blowing and the aircraft had drifted south-west before crash-landing about 50 miles from the scene of the combat. This extraordinary occurrence provided a striking example of the inherent stability in the flying characteristics of the R.E.8 – the aircraft had flown and landed itself without human assistance.29
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The R.E.8’s inherent stability regardless, few would dispute that overall it was a bad aircraft. How else describe a machine notorious for burning its crews alive? Statistics seem to bear this out since it sustained the second highest losses of all British aircraft on the Western Front, 661: a figure exceeded only by that for the Sopwith Camel at 870.30 Debate becomes heated over the issue of which of all these dozens of First World War aircraft were good. Bar-room and internet forum discussions still take place between armchair aviators bickering over which was the ‘greatest’ aircraft of a hundred years ago. Given that few of these people are qualified to fly aircraft of that vintage, and even fewer have ever flown a Fokker D.VII or an S.E.5a or a SPAD S.XIII, the discussion is about as meaningful as those similarly impassioned debates about the greatest-ever Formula One car that regularly occur in pubs between stout and opinionated men who would never fit into one, still less be given the chance to drive it. In one sense there was no truly ‘great’ aircraft in the whole of the first air war, and for a very good reason. At the time, the development of aircraft was everywhere so rapid that almost none escaped becoming obsolete after six months’ active service. Thanks to production delays many a type was already outmoded even as the first squadrons took delivery of it, having been leapfrogged in the interim by a new enemy machine: a syndrome that would reappear in both the Second World War and the Cold War. A combination of materials (or engine) shortage, battlefield emergency and administrative incompetence obliged several aircraft such as the B.E.2c to plod on above battlefields long after they should have been grounded.
The criterion for true ‘greatness’ surely has to reside in something more than a short-lived combat advantage, no matter how impressive that was at the time. A genuinely great aircraft must offer a more enduring quality such as longevity and all-round reliability (like the Douglas DC-3), utterly transcendent performance (like the Lockheed SR-71 ‘Blackbird’), overwhelming aesthetic beauty, like Concorde, or the capacity for constant uprating of its basic design like the B-52 bomber which, by the time the last one is scheduled to leave USAF service in 2040, will have racked up an astounding ninety years’ active service. None of the First World War’s aircraft comes close to measuring up to any of these yardsticks. That being said, a Sopwith Pup might still afford a skilled pilot immense pleasure even today, but the same could be said of a pre-1920 racing car without either machine qualifying for the timeless accolade of greatness.
This is obviously not to deny that hundreds of WWI pilots often found a new type wonderful and exhilarating to fly, usually because it was so much better than the machine they were used to and which had increasingly been feeling like a deathtrap when confronting the enemy. On the British side Sopwith’s Pup, Triplane and Camel, as well as the Royal Aircraft Factory’s S.E.5a, were a revelation to those who first flew them in combat; and at the time, as also today, each aircraft had its dedicated supporters. W. E. Johns’s punning title for an early collection of his stories, The Camels Are Coming, shows that fighter still had a certain legendary quality to it fourteen years after the war’s end, even though its active service life lasted a scant eighteen months after its introduction in the summer of 1917.
The stumpy little Camel was neither beautiful nor easy to fly. In fact it was notoriously tricky, ‘a fierce little beast’, as one airman described it, although those who mastered it found it a highly effective fighting machine. All the same, by late 1917 many German pilots reckoned their new Pfalz D.III was easily the Camel’s equal and in less than a year the Fokker D.VII was plainly the better fighter. One aviation historian, the late Peter Grosz (son of the German Expressionist painter Georg Grosz and an acknowledged expert on German aircraft), described the Camel baldly as ‘probably the most over-rated and accident-prone fighter in the Allied inventory’, going on to add that ‘surprisingly, only the D.H.5 was superior to the Pfalz in speed, climb rate and manoeuvrability’.31 ‘Accident-prone’ the Camel certainly was, which must partly explain why it so easily heads the list of British types lost. Many an experienced British pilot dreaded having to convert to it:
They were by far the most difficult of service machines to handle. Many pilots killed themselves by crashing in a right-hand spin when they were learning to fly them. A Camel hated an inexperienced hand, and flopped into a frantic spin at the least opportunity. They were unlike ordinary aeroplanes, being quite unstable, immoderately tail-heavy, so light on the controls that the slightest jerk or inaccuracy would hurl them all over the sky, difficult to land, deadly to crash: a list of vices to emasculate the stoutest courage, and the first flight on a Camel was always a terrible ordeal. They were bringing out a two-seater training Camel for dual work, in the hope of reducing that thirty percent of crashes on first solo flights.32
Nevertheless, once in the air the Camel had an agility all its own, partly down to the lightness of its construction and the weight of engine, guns, tanks and pilot all being concentrated in the nose. The gyroscopic effect of the engine was very marked, as might be expected with a mass of 350 lb whirling around at 1,250 rpm. Seen from the pilot’s little wicker seat the propeller rotated clockwise. This meant that if he climbed or turned to the right the nose would drop sharply, and if he dived or turned to the left the nose would rise. It also meant that lightning-fast right-handed turns were easily performed. Left-handed turns were another matter, however, and pilots found they could often turn 90 degrees left quicker by making a right turn of 270 degrees. This is not an ideal characteristic in any aircraft, but the most skilled pilots eventually found ways of instinctively going with rather than against the engine’s gyroscopic pull. The Camel is credited with being the top-scoring fighter of any side in the war, with 1,294 victories.33 On the other hand it killed 350 trainee pilots, or more than one non-combat death for every four enemy aircraft downed (but not necessarily with a fatality): a high price to pay.34 Like the contemporary French SPAD S.XIII, it stalled readily and spun viciously. Because of its tail-heaviness it could never for a moment be flown ‘hands-off’ and was therefore a very tiring aircraft to fly. Its combat success rate unquestionably makes the Camel one of the best fighters – and by that sole yardstick the best – of WWI. Yet that still does not make it a great aircraft because it so obviously could be improved, as was demonstrated by Sopwith’s next aircraft, the Snipe, which came late in the war and was willy-nilly adopted as the RAF’s first postwar standard fighter because there was nothing else available at the price. The Snipe was derived from the Camel and was equally manoeuvrable (hence its name), but it was much easier to control while affording the pilot far better all-round visibility. It was also slightly faster, being fitted with Bentley’s powerful BR.2 rotary engine.
Some biplanes were undoubtedly a good deal more elegant than others, and aircraft with the longer stationary (especially in-line) engines often looked more streamlined and better-proportioned. In this the German machines predominated because their designers were less wedded to rotary engines than were the French, the British, the Italians or the Russians. But the Royal Aircraft Factory’s S.E.5a with its stationary Hispano-Suiza or Wolseley Viper V-8 engine had the look of a serious modern fighter and was much respected by German pilots. Once initial problems with the supply and reliability of the engines had been overcome, the S.E.5a was looked on as the equal of the new Fokker D.VII, which ended the war with a fearsome reputation for all-round competence. After the Armistice the Allies, in punitive mood, impounded Germany’s entire fleet of Fokker D.VIIs as being too dangerous to be allowed to fall into others’ hands. This was really pure superstitiousness because by then the Fokker was already dated. Its top speed was only about 118 mph whereas Britain’s new Martinsyde F.4 ‘Buzzard’ was capable of a top speed at low level of 146 mph and was technically the fastest aircraft of the war. Unfortunately, it came too late to make the game-changing impression it otherwise might have done.
Long before then the war had determined the trajectory of aviation and of flying itself. A quirk of history ensured that what had started out as an entirely civilian enterprise had been comprehensively hijacked by the military. This is why considerations of a pilot’s pleasure – or even of his safety – did not figure on the list of specifications to which aircraft designers worked. This was also made clear in the matter of how to arm aeroplanes, where guns and bombs soon became the most significant part of many an aircraft’s payload, outweighing the aircrew both literally and metaphorically. The next chapter deals with this subject which, in the case of machine guns, was to afford a turning point in aerial warfare.