Dave Roberts talks us through a flight in the legendary Sopwith Camel
The Sopwith Camel, so the popular saying goes, offered its pilot three choices: the Victoria Cross, the Red Cross, or a wooden cross: the Camel downed more enemy aircraft than any other scout in W.W.I - it’s credited with 1294 victories - but it was also responsible for a lot of own-goals. In the 17 months during which the Camel was operational, it wasn’t just combat that claimed the lives of its pilots. Alas, 385 more died from ‘non-combat related causes’, many of them on home soil, far from the front, while either training or indulging in the new-fangled sport of ‘stunting’.
It would have been a wonder, then, if Sopwith’s terrier-like scout had not acquired a reputation as something of an enfant terrible of the air, reflecting the dramatic and dangerous glamour that surrounded the Great War’s newly created field of honour - the sky. Indeed, such was its reputation that, according to Capt. Norman Macmillan OBE MC AFC, many pilots came to regard the Camel as a particularly difficult aircraft to fly. However, this was a view, said Macmillan - who’d been an operational Camel pilot - “usually held by those who knew comparatively little of this type of aircraft.” He maintained instead that a pupil who could fly the Avro 504 properly, “could take the Camel off the ground and do straight-forward flying with certainty and confidence.”
In fairness, he also described the Camel as, “a fierce little beast,” and admitted that it would take upwards of 20 hours on type before the average pilot would begin to feel ‘thoroughly at home’ in the cockpit. Part of the reason for his determinedly positive note, however, was that Macmillan, who had been responsible for advanced training on a Camel station, was writing handling notes with a view to helping wartime instructors prepare pilots for their first solo in a Camel. Prior to the introduction of the two-seat Camel in late 1917 / early 1918, of course, a pilot’s first solo was also necessarily his first flight in a Camel - the time when, according to the statistics, one in three Camel crashes occurred!
A neat line of 8 Sqn 1F1 Camels at Mont St Eloi. B3757 had a busy but short career of just three months with the squadron, shooting down an Aviatik, a Rumpler and an Albatros.
No wonder, then, that for the initiate, the first Camel flight was often, “a terrible ordeal.” At least, that’s what Victor Yeates called it, and he should know: Yeates flew 248 hours on Camels on the Western Front, and survived the war to write the splendid Winged Victory. In his account of life in a scout squadron, Yeates appears as Tom Cundall, who has at least some of the attributes that legend has taught us to expect of a Camel pilot: “After tea he took up a new aeroplane... and put it through its paces. It pulled well, and when he put it over vertical and gave it a touch of elevator, the horizon fairly spun round. It was a good Camel, and Tom adopted it for his own.” Hurrah!
With Macmillan’s pilot notes in one hand, then, and Yeates’ Winged Victory in the other, we - well, you actually; there’s only room for one - can attempt a first flight in the Camel, to better understand how much of its reputation was bark, and how much was bite!
This is the 1000th aircraft built by Ruston Proctor. It was finished in a special colour scheme that didn’t go down well in France and was returned, destined never to serve a front line squadron.
NATURE OF THE BEAST
‘Fierce little beast’ really does say it all: the wings are just 28ft in span, and from the nose of the Clerget engine to the tip of the neat, spoon-shaped tail, the Camel measures only 18ft 9in. It didn’t carry much weight, either - 950 lbs empty, or 1482 lbs with a war load on board, including the pilot, his scarf, and lucky mascot. What’s more, the principal masses - the engine, guns, controls, fuel and pilot - were concentrated in just seven feet of fuselage, an arrangement that helped to make the Camel highly manoeuvrable, especially when coupled to the torque of the rotary engine.
Camels were powered by a variety of motors - Gnomes or Le Rhones, or Bentley BR1s in the Royal Navy Air Service aircraft. Both Macmillan and Yeates, however, flew Camels with Clerget engines. Costing £907.10s a time - more than the rest of the aircraft put together! - the Clerget gave the Camel a power-to-weight ratio comparable to, say, an old Austin Mini with a 130hp engine. The difference, however, is that the Mini’s engine would neither rotate, nor would it be attached to an 8ft 6in propeller - characteristics that are fundamental to the Camel’s nature.
‘Newton Abbott’ was delivered to 65 Sqn on 8th Aug 1918 only to be shot down the following morning. Lt Illingworth was taken prisoner.
The rotating mass of the engine and prop’ acted as a gyroscope, and gyroscopes have two key properties - rigidity and precession. Rigidity means that the gyro’ will remain fixed in space and resist any external force trying to tilt it on its spin axis. The strength of this resistance is a function of its mass, the distribution of that mass relative to the axis of rotation, and the speed of rotation. In short, the greater the mass, the further it is from the axis, and the faster it spins, the greater the rigidity. You can see that the Clerget’s nine cylinders, which rotated at up to 1200rpm, distributed its 381 lbs fairly widely. The result was that it took quite a push to shift the engine and prop’ about their axis, and thanks to Newton’s Third Law it would push back just as hard - which is where precession comes in.
When you apply a force to a gyro’, it reacts as if the force had been applied at a point offset by 90° in the direction of rotation. In the Camel, the engine and prop’ rotated clockwise as viewed by the pilot. So, if you imagine sitting in the cockpit and pushing on the bottom of the spinning propeller disk (the six o’clock position) as if to raise the nose of the aeroplane, the rotating disc would react as if you’d actually pushed it in the nine o’clock position - the gyro’ would precess and tilt to the right.
It’s this property that made the Camel turn and roll faster than you can say ‘conservation of angular momentum’. It is also, Yeates tells us, why many pilots killed themselves by crashing in a right-hand spin when they were learning to fly Camels. Don’t worry about that for the moment, though. Just get into the aeroplane and observe the good Captain’s advice to accustom yourself to the seeming smallness of the wings and, “fasten the safety belt tightly...”
Camels would often take-off at sea from the deck of a lighter that would be towed into wind at top speed by a destroyer. This was the take-off method used by Lt SD Culley when he shot down a Zepplin off Borkum Riff lightship on 11th August 1918.
Now, Macmillan’s notes tell us that the Camel’s controls are sensitive in pitch, but less so in roll and yaw. Despite this, the stick needs to be pushed fully forward on take-off to raise the tail. This may sound suicidal, but it’s essential because the aeroplane is markedly tail-heavy in the take-off. This is partly a consequence of the full fuel tanks - there’s around 266 lbs of petrol sitting immediately behind you - and partly because of the way the Camel is rigged. The idea, apparently, is that by mid-patrol, when the aeroplane’s flying around its optimum operating altitude of 12,000ft, the set of the rigging will allow the craft to maintain more or less level flight with minimum stick load, which is obviously less fatiguing for the pilot. You can see, however, how this set-up may have contributed to the stalling accidents shortly after take-off that were not uncommon among inexperienced Camel pilots - a problem compounded by the Clerget’s sensitivity to fine adjustment of the fuel mixture. The rotary was susceptible to rich-cuts, and since a stall was generally followed by a spin, things could quickly become uncomfortable if this happened shortly after take-off: “One of the rear men,” said Yeates, recalling just such an incident, “had his engine cut clean out when he had reached 50ft, and he turned back to land on the aerodrome instead of going straight on. He tried to keep his nose up long enough to complete his turn downwind and, of course, lost flying speed and fell into a spin that only lasted half a turn before the machine crumpled on the ground.”
With that cheery thought to concentrate the mind, I’ll wave you off with the advice that Yeates was given immediately prior to his first flight in a Camel: “You may find it a bit difficult to keep straight at first,” he was told. “Keep just a shade of left rudder on to counteract the twist to the right; when you’re on anything like full throttle, you can feel the engine pulling to the right all the time. Don’t get wind up, and you’ll be quite happy.”
This replica Camel was built in 1969 by the Slingsby Aircraft Company. It’s now on static display in the FAA museum at Yeovilton.
GETTING INTO THE AIR
One place that you do need a bit of wind, though, is in the 24-gallon main fuel tank, which is pressurised using a pump in the cockpit; taking-off on the four-gallon gravity-feed emergency tank isn’t recommended.
The take-off itself will only last for about 150 yards: with a nine to 13kt headwind, the Camel will fly itself off the ground at an indicated 45kts, while a 60kt climb will put another 1000ft between you and the ground every minute - providing you remember to use your ear to keep the Clerget running sweetly, that is, and steadily lean off the fuel mixture.
Now that you’re up, you’ll have discovered for yourself that, “a Camel has to be held in flying position all the time, and is out of it,” as Yeates warned, “in a flash.” As you’ve no turn-and-slip gauge, you’ll have to judge your balance by the seat of your pants and the feel of the wind on your face: a buffeting on either ear lets you know that you’re side-slipping, and the chances are it’ll be your left ear taking the bashing as the engine yaws you to the right.
Gentle turns shouldn’t cause you any problems, providing you’re light on the controls and use rudder to help initiate the turns and counter the adverse yaw. Once the turn is started - whether to left or right - you’ll find that you need some left rudder, again to counter the pull of the engine. Don’t mess about with this stuff, though - scouts weren’t built for gentle turns. “A Camel,” Yeates’ instructor told him, “is an aeroplane not a house with wings” - a slighting reference, no doubt, to the 504 - “and you can put ‘em over vertical and back again quicker than you can say it.”
Oh, before you try that, a quick word on spinning. The Camel’s often accused of having vicious spin characteristics. The fact is that, while it seems happy to stall and fall into a spin, according to Macmillan the recovery is quite without drama: from an erect spin relax on the stick till it’s slightly forward of neutral and centralise the rudder. Stopping a right-hand spin, he says, takes less than half a turn, whilst a left-hand takes a little more.
Camel B3941 is pictured here alongside a Sopwith Pup. It was delivered to 84 Sqn at Lilbourne in August 1917.
A TURN TO THE LEFT...
Right then, with the power on try rolling left and pulling back slightly on the stick: the horizon, as Yeates noted earlier, fairly spins around! You’ll need to hold off the bank angle, mind, as the torque of the engine against the airframe tries to roll you further left, while at the same time using plenty of left rudder (some sources say full left rudder) to stop the nose being pushed upwards. I know, you were expecting left roll to produce left yaw, but that’s precession at work, pulling the airframe around the sky.
“It was just this instability,” Yeates said, “that gave Camels their good qualities of quickness in manoeuvre,” and you won’t find that quickness and manoeuvrability better demonstrated - with a Clerget, at least - than in anything that involves going to the right, when it’s aided by precession!
Steep turns, for example, were so quick, and could involve such a dramatic lowering of the nose that full left rudder was required to keep it above the horizon. Contemporary flying notes warned against inducing a high-speed stall by applying too much elevator (apparently, it’s only necessary to move the top of the stick sideways and back by two and three inches respectively to achieve a tight turn), and some even suggested that pilots do not turn to the right under 1000ft until they were thoroughly familiar with the machine. Once mastered, though, Macmillan - who fought for five months in Camels - reckoned that, “these qualities of speedy manoeuvre made her more than able to hold her own with faster flying and quicker climbing stationary-engine machines.” The Camel, for example, could make three turns to the right for every two made by the Albatross DV.
This Camel (B2541) had a busy career serving at Cranwell, Hendon, Yeovil and Martlesham Heath to name but a few. It never served with a front line unit.
...AND A FLICK TO THE RIGHT
The Camel’s party piece, however, was the flick turn to the right: pitch up to about 30, pull back sharply on the stick while applying full rudder and reducing the power by leaning the mixture. From this position you have a number of options. You can either centralise the rudder and turn the manoeuvre into a dive; let the turn develop into a roll, in which case one set of 1918 flying notes suggests that you, “take off rudder when upside-down and you’ll come butter-side up in normal flying position.” Yeates, however, claimed that splitting the difference and executing a half-roll was, “the only stunt useful in fighting,” and, “nothing would half-roll like a Camel. If you were going the wrong way,” he said, “it was the quickest known method of returning in your own slipstream!” These manoeuvres to the right could be so extreme, in fact, that it was claimed that the Camel could about-face in less than twice the length of the fuselage, and that flick rolls could be executed without loss of height.
The Camel’s big problem was that it wasn’t fast. Its top speed was just 113mph at 10,000ft, and as Yeates said, “a Camel could neither catch anything by surprise, nor hurry away from an awkward situation, and seldom had the option of accepting or declining combat.”
One of several Camels operated by 26 Training Depot Station at Edzell, Angus. Like so many other post First World War Training Depot Stations, the unit was disbanded in April 1919.
HOME FOR TEA AND MEDALS
If you want to know about fighting in the Camel, track down a copy of Chaz Bowyer’s Sopwith Camel: King of Combat. For the moment, however, you’d do better to try and get yourself back on the ground before you run out of juice.
Speaking of which, did we discuss forced landings? No? Well, if the engine should die on you, Macmillan recommends a brisk 45° side-slip into a suitable field, taking care not to pick up speed, and to take off all of the side-slip before the wheels touch - the Camel undercarriage has very low resistance to side-loadings. But then, you’d be in good company - Yeates pranged his kite four times.
The conventional approach, meanwhile, is flown in a 60mph glide. And do watch your speed: now that you’ve burnt off most of your fuel, the aircraft balance has shifted to produce a nose-heavy attitude. And - oh dear - the engine doesn’t sound happy on that closed throttle, does it. Unfortunately, the Clerget won’t run smoothly at low rpm, and the last thing you want is for it to foul its plugs with Castor oil so that it won’t pick up when you need it. The best thing to do, then, is set half revs and use the blip-switch on the joystick’s spade grip to reduce power by cutting the spark to a number of the cylinders. You’ve got to be judicious with your use of the blip-switch, mind, as once again gyroscopics will lay a trap for the unwary, particularly if you’re S-turning to lose some height. Restoring power suddenly could either lead to a side-slip off a right-hand turn - which is uncomfortable close to the ground - or a stall off a left-hand turn, which will take 100 - 200ft to recover.
Providing the speed is right, says Macmillan, “many pupils find a Camel easier to land than an Avro.” Clearly, he was writing at a time when all aircraft were tail-draggers (happy days!) and pilots were well-practiced at rounding out 6 to 12in above the grass, letting the aircraft settle - the Camel stalls at 33kts - and reining in any thoughts it might have of further flying by bringing the stick fully back.
And welcome home, sir!
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