John Dunne’s Uncapsizable Aeroplanes (Oct2010)
John William Dunne (1875-1949) followed his father into the army and fought in the Boer War. Invalided home he had time to pursue his dream of building a stable flying machine that would need no steering and be ‘uncapsizeable’. Like several other early pioneers, he was inspired by the remarkable gliding performance of the seed of the zanonia tree (pictured right). He experimented with models and gliders and when he was posted to the Army Balloon Factory at Farnborough in 1905 he began the construction of what would become Britain’s first military aeroplane.
In 1907 the Dunne D.1 glider was taken by rail to the Duke of Atholl’s estate in Scotland and, in secrecy, tested by Colonel Capper, CO of the Balloon Factory. Although the 8 second flight ended in the inevitable crash which slightly injured Capper it was deemed to be successful enough for Dunne to continue his work. The D.3 glider was an improvement and was followed by the powered D.4 which, although it flew for 120 feet on 10 December 1908, Dunne admitted was ‘more a hopper than a flier’. All his designs had a characteristic arrow-head shape inspired by the zanonia seed. However, the Army Council had lost interest in Dunne’s work and so he left the Balloon Factory.
Dunne formed a small company to continue his work on the D.5. This was built for him by the Short brothers. Its engine drove two propellers by chains. The swept back wings gave stability in pitch because they were built with wash-out, a progressive reduction in the angle of incidence towards the tips. The only controls were the elevons, hinged surfaces at the wingtips which combined the functions of elevator and ailerons. There was no rudder. The vertical panels at the wingtips gave directional stability. It was said that the aeroplane ‘couldn’t be side-slipped’.
Dunne took the opportunity to show off his newly-built machine when he invited Griffith Brewer and Orville Wright (pictured right) to see its capabilities in December 1910. Brewer was a prominent member of the Royal Aeronautical Society and the Royal Aero Club which was responsible for awarding aviators’ certificates. He was a pioneer balloonist and was the first Englishman to fly in an aeroplane – as a passenger with Wilbur Wright in France in 1908. He became a close friend of the Wrights and was appointed their agent in England. He also introduced them to the Short brothers who took a licence to build Wright-type biplanes. Dunne’s account of this occasion makes fascinating reading.
Obviously, the first thing to do was to show that the machine could fly as well and as strongly as those of the ordinary T-shape, to exhibit the power of control and manoeuvre given by the two little steering flaps and above all to show that with this type of machine good turns, with the correct amount of banking and no side-slipping, could be effected without recourse to the complicated ‘three-rudder’ system.
I therefore contented myself with a closed circuit, allowing the machine to climb to 100 ft on the turn and as this was the first time I had turned at any height I confined my attention to making a neat job of it and made no particular attempt to show off the automatic stability of the machine until it came to descending.
It is a well-known rule of flying that, before throttling the engine, the machine’s bow should be pointed slightly downwards to avoid the loss of speed that would otherwise ensue and it is in the proper manipulation of the levers immediately afterwards to maintain speed and keep the machine under control that the trained aviator has to exercise his greatest skill. So, both in this flight and in the second, I first locked the levers in the central position to which they are left while flying, then throttled and immediately threw up my arms and left the machine to come down from the flying tilt to the gliding tilt of its own accord and then make its way earthward. The steep slope of the ground at the point of landing rendered it unsafe to attempt the requisite flattening of the trajectory before touching earth by the use of the throttle alone, so at the last moment, I used the flap-controls for this purpose.
The next point was to prove the safety of the machine. As we have no space for passengers in the present apparatus I suggested that I should go around the same short circuit and carry out the writing test. I proposed this as I know of nothing else which so thoroughly puts to the proof the aviator’s real trust in his machine’s fitness to look after itself compelling, as it does, absolute detachment of the mind. One may eat, smoke, click a camera, take off one’s coat, or do a hundred other things and all the time keep one’s eye ahead to see what the machine is really doing and be ready to snatch a lever if necessary. But when writing, sitting low in our big boat, one’s attention is perforce completely withdrawn from one’s surroundings.
I therefore contented myself with a closed circuit, allowing the machine to climb to 100 ft on the turn and as this was the first time I had turned at any height I confined my attention to making a neat job of it and made no particular attempt to show off the automatic stability of the machine until it came to descending.
It is a well-known rule of flying that, before throttling the engine, the machine’s bow should be pointed slightly downwards to avoid the loss of speed that would otherwise ensue and it is in the proper manipulation of the levers immediately afterwards to maintain speed and keep the machine under control that the trained aviator has to exercise his greatest skill. So, both in this flight and in the second, I first locked the levers in the central position to which they are left while flying, then throttled and immediately threw up my arms and left the machine to come down from the flying tilt to the gliding tilt of its own accord and then make its way earthward. The steep slope of the ground at the point of landing rendered it unsafe to attempt the requisite flattening of the trajectory before touching earth by the use of the throttle alone, so at the last moment, I used the flap-controls for this purpose.
The next point was to prove the safety of the machine. As we have no space for passengers in the present apparatus I suggested that I should go around the same short circuit and carry out the writing test. I proposed this as I know of nothing else which so thoroughly puts to the proof the aviator’s real trust in his machine’s fitness to look after itself compelling, as it does, absolute detachment of the mind. One may eat, smoke, click a camera, take off one’s coat, or do a hundred other things and all the time keep one’s eye ahead to see what the machine is really doing and be ready to snatch a lever if necessary. But when writing, sitting low in our big boat, one’s attention is perforce completely withdrawn from one’s surroundings.
I ran down across the wind, hopped off, touched again, and then began to rise steadily. As soon as I saw that I should clear the bushes on the boundary dyke I locked the levers and felt for the paper and pencil given to me by Mr Griffith Brewer. The paper was in one pocket and the pencil in another; by the time I had got them ready I must have flown a considerable way.
I started to set down certain points I was anxious to observe and remember. First I counted the divisions on the revolution indicator, which has no figures between the 1,000 and 1,500 marks. When I began to set them down I found that, unfortunately, it was almost impossible to write on the thin paper with only the fingers and palm of the hand as a backing thereto and that a certain amount of excitement rendered that task still more difficult. I then observed the position of the levers relative to the toothed racks and made a note of that. I next looked about the inside of the boat for something else to note and, while doing so, became aware of the violent wind in my face, which, curiously, I had entirely failed to notice on the previous flight.
As I had been anxious to ascertain how far the front screen shielded the aviator, I wrote this fact down. From the time I had first locked the levers till now I had not paid the smallest attention to what the machine was doing or where it was going. It had been left to follow its own fancy and might at this time be anywhere or in any position for all I knew. However, looking up I saw that it was still level, but had drifted downwind and was aiming to hit a wind-pump, so I decided to commence the turn.
I separated the levers, holding them until the turn started, noted its radius, which was shorter than I required, diminished the difference between the lever positions, locked them, waited a little time, hands off, until I was satisfied with the radius of the turn and, with the rapidity with which the machine was mounting, got hold of my paper and, with some difficulty wrote ‘turning now’. Looking over the port bow I saw a farmhouse nearly beneath me and, realising that the circle was now bigger than I intended and also that I was much higher than I thought, I pushed each lever into the fourth notch and, sitting with my hands in my lap, allowed the machine to swing itself sharply round. Then I locked the levers centrally and sat back, but did not continue writing as I was puzzled by a momentary failure to recognise the ground below me.
I am not a balloonist and am unused to heights. After a moment I realised that a little dark green blob was the pond in the middle of the ground. So I turned the machine towards it and then wrote ‘straight again’. By the time I got that down I saw that I should have to descend at once if I meant to get back to my starting point. So I moved the machine’s nose a degree or two round, aiming at the point in question, returned each lever carefully to its central notch , throttled the engine and held up my arms. Instantly the machine’s head dropped a little and, without any abatement of forward speed, she began to sink towards the ground. I landed her as described before.
The D.5 was developed by fitting a lighter, more reliable, single propeller. After an accident, it was modified and rebuilt, emerging as the D.8, Dunne’s most successful model. In 1913, he flew it from Eastchurch to Paris, where it was enthusiastically received. The Nieuport company ordered one, with plans to build them under licence. Dunne arranged for Shorts to produce another D.8 and for two more to be built at Hendon. It was at Hendon where the D.8 was displayed to the public in October 1913. Two aeroplanes were ordered by the RFC and the Royal Navy showed interest in the design as a trainer. It was this that might have been its undoing.
The Dunne was undoubtedly successful as a safe and stable machine but the Navy considered it would be dangerous to use it for training pilots. It would instil a false sense of security incompatible with other military types designed for quick control and manoeuvrability. The War Office also lost interest.
To compensate for this severe disappointment, a new avenue opened when W Starling Burgess, an American plane and boat builder, acquired a licence. During 1914, Burgess produced a total of thirteen of Dunne’s designs. One of these, powered by a nine-cylinder Salmson engine, was the first aircraft to be purchased by the US Signal Corps. There were some private sales and the US Navy ordered six. But there was a fire at the factory and the Navy didn’t renew the order.
To compensate for this severe disappointment, a new avenue opened when W Starling Burgess, an American plane and boat builder, acquired a licence. During 1914, Burgess produced a total of thirteen of Dunne’s designs. One of these, powered by a nine-cylinder Salmson engine, was the first aircraft to be purchased by the US Signal Corps. There were some private sales and the US Navy ordered six. But there was a fire at the factory and the Navy didn’t renew the order.
Enter the Canadian military. Their first expeditionary force was soon to sail for France in October 1914 to play its part in the Great War and their flying arm possessed not a single aeroplane. A hastily-appointed ‘provisional commander’, Capt Janney, was sent across the border to find one. Availability was a prime requirement and the Burgess company was persuaded to part with their well-used demonstration model floatplane - after a quick overhaul. The company pilot left for Canada with Janney as ‘navigator’
A forced landing took place within an hour of take-off and the two were briefly held as suspected enemy agents. A second problem resulted in a rescue by a passing motor boat and a replacement of the old engine. However, they reached Quebec in time and the Canadian Aviation Corps (two officers, one mechanic, one Burgess-Dunne floatplane) embarked on the SS Athenia. Tied on an open deck it was damaged in transit and languished, unwanted, on an English dockside. Eventually it disappeared into obscurity.
Its designer, too, faded from the aeronautical scene when ill health forced his retirement. He did not leave unrecognised. With the rare distinction of having designed the first military aeroplanes of the United Kingdom, Canada and the US Army and also producing the first aeroplane to be flown on auto-pilot his considerable achievements were acknowledged by his investment as a Fellow of the Royal Aeronautical Society
Its designer, too, faded from the aeronautical scene when ill health forced his retirement. He did not leave unrecognised. With the rare distinction of having designed the first military aeroplanes of the United Kingdom, Canada and the US Army and also producing the first aeroplane to be flown on auto-pilot his considerable achievements were acknowledged by his investment as a Fellow of the Royal Aeronautical Society
Dunne’s work had its legacy. He was consulted by Professor G T R Hill who had been a test pilot with the Royal Aircraft Factory. Hill’s aim was to produce a safe aeroplane which avoided the dangers of stalling. In 1928, a series of gliders and powered test planes resulted in the Pterodactyl, made by Westland and clearly, with Air Ministry interest. The design was developed and the Mk 4 was the first tailless aircraft to be spun, looped and rolled.
The Mk. 5, powered by a 600 hp RR Goshawk was intended as a two-seat fighter, the rear-facing gunner having an exceptional field of fire. Although it had a commendable top speed of 190 mph no production order followed.
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Others who followed in Dunne’s footsteps were the Granger brothers of Nottingham who outdid Hill with a more outrageous name when they built their Archaeopteryx in 1930. For a time it lived and flew at Old Warden. It’s now back with the Granger family and being rebuilt with the assistance of Rod Millinchip.
The final accolade comes from Jack Northrop, the man who carried the development of tailless aeroplanes towards the current B-2 stealth bomber. He began his work in 1929 and acknowledged that part of his inspiration came from the success of John William Dunne in 1910.
The final accolade comes from Jack Northrop, the man who carried the development of tailless aeroplanes towards the current B-2 stealth bomber. He began his work in 1929 and acknowledged that part of his inspiration came from the success of John William Dunne in 1910.