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65-534: The Dunne D.8 of 1912 was a tailless swept wing biplane , designed by J. W. Dunne to have inherent stability. One example was supplied to RAE Farnborough . License-built Burgess-Dunne models were used by the US Signal Corps and United States Navy and the short-lived Canadian Aviation Corps . It was the latter's first and only warplane. J. W. Dunne's first swept biplane wing aircraft, designed to have automatic stability, dated from his employment at

130-469: A War Office order for two D.8s, though one was cancelled because of late delivery. The other was delivered to Farnborough on 3 March 1914, where it was given the RFC number 366. It made several flights on 11 March piloted by N. S. Percival, who had flown the first D.8 many times at Eastchurch and was now an RFC officer. The general judgement was that in the search for balance between stability and controllability,

195-487: A bell-shaped lift distribution which minimises induced drag for the aircraft weight. He applied this distribution in the "Prandtl-D" series of designs. By the end of 2017, he had flown three such research models. War Office The War Office has referred to several British government organisations in history, all relating to the army. It was a department of the British Government responsible for

260-515: A fuselage nacelle between the planes with rear-mounted pusher propeller and fixed endplate fins between each pair of wing tips. After his Army work had ended, in 1910 the D.5 biplane was witnessed in stable flight by Orville Wright and Griffith Brewer , who submitted an official report to the Royal Aeronautical Society to that effect. It thus became the first aeroplane ever to achieve natural stability in flight, as well as

325-470: A high angle of attack while the back section is more horizontal and contributes no lift, so acting like a tailplane or the washed-out tips of a swept wing. Reflex camber can be simulated by fitting large elevators to a conventional airfoil and trimming them noticeably upwards; the center of gravity must also be moved forward of the usual position. Due to the Bernoulli effect , reflex camber tends to create

390-518: A highly swept delta wing the distance between trailing edge and aerodynamic centre is larger so enlarged surfaces are not required. The Dassault Mirage tailless delta series and its derivatives were among the most widely used combat jets. However even in the Mirage, pitch control at the high angles of attack experienced during takeoff and landing could be problematic and some later derivatives featured additional canard surfaces. A conventional aeroplane

455-421: A pair of levers, one either side of the pilot. The D.8 initially used just one pair of elevons, mounted on the upper wing, a rectangular cutout in the side curtains allowing for their movement as on the D.5. Large parts of the aircraft were manufactured by Short Brothers . The D.8's water-cooled 4-cylinder, 60 hp (45 kW) Green engine directly drove a single pusher propeller, saving weight compared with

520-718: A separate Minister of Defence for the first time in 1947. In 1964, the present form of the Ministry of Defence was established, unifying the War Office, Admiralty, and Air Ministry. As early as 1718 letters from the Secretary at War were addressed from "The War Office". His department had several headquarters in London until it settled at Horse Guards in Whitehall during 1722. It remained there until 1858. Then, following

585-440: A series of tailless aircraft intended to be inherently stable and unstallable. Inspired by his studies of seagulls in flight, they were characterised by swept wings with a conical upper surface. The cone was arranged so that the wing twisted progressively outwards towards the tips creating negative incidence, and hence negative lift, in the outboard sections, creating overall stability in both pitch and yaw. A single control surface on

650-413: A small downthrust, so the angle of attack of the wing is increased to compensate. This in turn creates additional drag. This method allows a wider choice of wing planform than sweepback and washout, and designs have included straight and even circular (Arup) wings. But the drag inherent in a high angle of attack is generally regarded as making the design inefficient, and only a few production types, such as

715-436: Is a tailless design which also lacks a distinct fuselage , having the pilot, engines, etc. located wholly or partially in the wing. A conventional fixed-wing aircraft has a horizontal stabiliser surface separate from its main wing. This extra surface causes additional drag requiring a more powerful engine, especially at high speeds. If longitudinal (pitch) stability and control can be achieved by some other method (see below),

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780-432: Is an example. Many early designs failed to provide effective pitch control to compensate for the missing stabiliser. Some examples were stable but their height could only be controlled using engine power. Others could pitch up or down sharply and uncontrollably if they were not carefully handled. These gave tailless designs a reputation for instability. It was not until the later success of the tailless delta configuration in

845-589: Is augmented by the aerodynamic techniques described. A classic example is the Rogallo wing hang glider, which uses the same sweepback, washout and conical surface as Dunne. Stability can also be provided artificially. There is a trade-off between stability and maneuverability. A high level of maneuverability requires a low level of stability. Some modern hi-tech combat aircraft are aerodynamically unstable in pitch and rely on fly-by-wire computer control to provide stability. The Northrop Grumman B-2 Spirit flying wing

910-634: Is known to have influenced later designers such as John K. Northrop (father of the Northrop Grumman B-2 Spirit stealth bomber). After WWI, pilot Geoffrey T. R. Hill also sought a stable, unstallable design. Dunne gave some help initially and Hill went on to produce the Pterodactyl series of tailless aircraft from the 1920s onwards. Hill also began to develop the theory of the intrinsically stable aerofoil and incorporated it into his designs. German theorists further developed

975-414: Is unstable in yaw and needs a tail fin to keep it straight. Movement of the ailerons creates an adverse yaw pulling it out of the turn, which also has to be compensated by the rudder . While a swept wing is stable in straight flight, it still experiences adverse yaw during a turn. One solution is to give the wing sufficient twist for the outer section to angle downwards and give negative lift. This reverses

1040-618: The Army Balloon Factory (later RAE Farnborough ) during 1906–09. After leaving Farnborough, Dunne set up a private company, the Blair Atholl Aeroplane Syndicate Ltd. Its first aircraft was the Dunne D.5 . When this crashed in 1911 it was rebuilt as the first D.8. The two models shared similar wings and the same engine, but the D.8 had a single pusher propeller instead of the chain-driven pair of

1105-906: The Commander-in-Chief of the Forces , the Secretary at War , and the twin Secretaries of State ; most of whose military responsibilities were passed to a new Secretary of State for War in 1794. Others who performed specialist functions were the controller of army accounts, the Army Medical Board , the Commissariat Department, the Board of General Officers, the Judge Advocate General of

1170-638: The Council of War , an ad hoc grouping of the King and his senior military commanders which managed the Kingdom of England 's wars and campaigns. The management of the War Office was directed initially by the Secretary at War , whose role had originated during the reign of King Charles II as the secretary to the Commander-in-Chief of the Army . In the latter part of the 17th century, the office of Commander-in-Chief

1235-803: The DINFIA . Similar to the DH.108, the twin-jet powered 1948-vintage Northrop X-4 was one of the series of postwar X-planes experimental aircraft developed in the United States after World War II to fly in research programs exploring the challenges of high-speed transonic flight and beyond. It had aerodynamic problems similar to those of the DH.108, but both X-4 examples built survived their flight test programs without serious incidents through some 80 total research flights from 1950 to 1953, only reaching top speeds of 640 mph (1,035 km/h). The French Mirage series of supersonic jet fighters were an example of

1300-498: The Fauvel and Marske Aircraft series of sailplanes, have used it. A simpler approach is to overcome the instability by locating the main weight of the aircraft a significant distance below the wing, so that gravity will tend to maintain the aircraft in a horizontal attitude and so counteract any aerodynamic instability, as in the paraglider . However, in practice this is seldom sufficient to provide stability on its own, and typically

1365-595: The Imperial General Staff was virtually dismantled. Its role was replaced effectively by the Committee of Imperial Defence , which debated broader military issues. The War Office decreased greatly in importance after the First World War, a fact illustrated by the drastic reductions of its staff numbers during the inter-war period. Its responsibilities and funding were also reduced. In 1936,

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1430-516: The Me 163 Komet . It was the only rocket-powered interceptor ever to be placed in front-line service, and was the fastest aircraft to reach operational service during the war. In the 1930s, Walter and Reimar Horten started to build simple tailless gliders, the first of which flew in 1933. The Hortens designed the world's first jet-powered flying wing , the Horten Ho 229 In parallel with Lippisch, in

1495-533: The Nine Years' War and who, from his appointment as Secretary in 1684, had greatly expanded the remit of his office to cover general day-to-day administration of the Army. After Blathwayt's retirement in 1704, Secretary at War became a political office. In political terms, it was a fairly minor government job (despite retaining a continued right of access to the monarch) which dealt with the minutiae of administration, rather than grand strategy. The Secretary, who

1560-534: The Northrop B-2 Spirit bomber. Disadvantages include a potential sensitivity to trim . Tailless aircraft have been flown since the pioneer days; the first stable aeroplane to fly was the tailless Dunne D.5 , in 1910. The most successful tailless configuration has been the tailless delta , especially for combat aircraft, though the Concorde airliner is also a delta configuration. NASA has used

1625-488: The Tupolev Tu-144 , were tailless supersonic jet airliners, with ogival delta wings. The grace and beauty of these aircraft in flight were often remarked upon. The American Lockheed SR-71 Blackbird strategic reconnaissance aircraft is the fastest jet powered aircraft, achieving speeds above Mach 3. The NASA Preliminary Research Aerodynamic Design To Lower Drag (PRANDTL-D) wing has been developed by Al Bowers at

1690-432: The 'tailless' description for the novel X-36 research aircraft which has a canard foreplane but no vertical fin. A tailless aircraft has no other horizontal surface besides its main wing. The aerodynamic control and stabilisation functions in both pitch and roll are incorporated into the main wing. A tailless type may still have a conventional vertical tail fin ( vertical stabilizer ) and rudder . A flying wing

1755-598: The 1867 confederation of the Dominion of Canada , was to split the military administration of the British Empire much as the War and Colonial Office had: In February 1855, the new Secretary of State for War was additionally commissioned as Secretary at War, thus giving the Secretary of State oversight of the War Office in addition to his own department. The same procedure was followed for each of his successors, until

1820-791: The Armed Forces , the Commissary General of Muster , the Paymaster General of the forces , and (particularly with regard to the Militia ) the Home Office . The term War Department was initially used for the separate office of the Secretary of State for War; in 1855, the offices of Secretary at War and Secretary of State for War were amalgamated, and thereafter the terms War Office and War Department were used somewhat interchangeably. The War Office developed from

1885-610: The Army Council was recommended by the War Office (Reconstitution) Committee, and formally appointed by Letters Patent dated 8 February 1904, and by Royal Warrant dated 12 February 1904. The management of the War Office was hampered by persistent disputes between the civilian and military parts of the organisation. The government of H.H. Asquith attempted to resolve this during the First World War by appointing Lord Kitchener as Secretary for War. During his tenure,

1950-605: The Cabinet. The disastrous campaigns of the Crimean War resulted in the consolidation of all administrative duties in 1855 as subordinate to the Secretary of State for War, a Cabinet job. He was not, however, solely responsible for the Army; the Commander-in-Chief had a virtually equal degree of responsibility. This was reduced in theory by the reforms introduced by Edward Cardwell in 1870, which subordinated

2015-470: The Commander-in-Chief to the Secretary for War. In practice, however, a large influence was retained by the conservative Commander-in-Chief Field Marshal Prince George, 2nd Duke of Cambridge , who held the post between 1856 and 1895. His resistance to reform caused military efficiency to lag well behind that of Britain's rivals, a problem that became obvious during the Second Boer War . The situation

Dunne D.8 - Misplaced Pages Continue

2080-430: The D.5's chain drive. As a consequence of the propeller position the fuselage was shortened at the rear; it was also extended in the nose. This first D.8 was a single-seater like its D.5 predecessor, the pilot sitting at mid chord. The undercarriage was complex, comprising a narrow-track pair of sprung wheels with wingtip skids. It featured undamped, opposing springing and an elaborate anti-noseover skid. The Green engine

2145-399: The D.5. Their fuselages and undercarriages were also different. The D.8 was a tailless four bay unstaggered biplane with constant chord wings swept at 32°. The wings were built up around two spruce spars, the forward one forming the leading edge. To help achieve stability the incidence and interplane gap decreased outboard, the former becoming negative. This washout on tips well behind

2210-666: The D.8 was fitted with an 80 hp Gnome engine which greatly improved performance and reliability. In August 1913 Commandant Felix piloted it across the English Channel from Eastchurch to Villacoublay , Paris . Nieuport had obtained a licence to build the D.8 and Felix gave a series of demonstration flights in France on their behalf. A Nieuport-built Dunne appeared at the Paris Aero Salon in December 1913. Like

2275-503: The Dunne design overemphasised the former. Data from Bruce 1992 General characteristics Performance Related lists [REDACTED] Media related to Dunne D.8 at Wikimedia Commons Tailless aircraft Theoretical advantages of the tailless configuration include low parasitic drag as on the Horten H.IV soaring glider and good stealth characteristics as on

2340-499: The NASA Armstrong Flight Research Center . Bowers was inspired by the work of Ludwig Prandtl and, like Dunne, by watching bird flight. As with the Dunne design, it has a wing twist sufficient to set the wing tips at a negative angle and create the same positive roll-yaw coupling. Bowers developed a quantitative analysis of the lifting characteristics, leading to his more general discovery of

2405-537: The US, Jack Northrop was developing his own ideas on tailless designs. The N-1M flew in 1941 and a succession of tailless types followed, some of them true flying wings. In the 1940s, the British aircraft designer John Carver Meadows Frost developed the tailless jet-powered research aircraft called the de Havilland DH.108 Swallow , built using the forward fuselage of the de Havilland Vampire jet fighter. One of these

2470-792: The administration of the British Army between 1857 and 1964, when its functions were transferred to the new Ministry of Defence (MoD). It was at that time, equivalent to the Admiralty , responsible for the Royal Navy (RN), and (much later) the Air Ministry , which oversaw the Royal Air Force (RAF). The name 'War Office' is also given to the former home of the department, located at the junction of Horse Guards Avenue and Whitehall in central London. The landmark building

2535-510: The adverse yaw action of the ailerons, helping the plane into the turn and eliminating the need for a vertical rudder or differential-drag spoilers. The bell-shaped lift distribution this produces has also been shown to minimise the induced drag for a given weight (compared to the elliptical distribution, which minimises it for a given span). Between 1905 and 1913, the British Army Officer and aeronaut J. W. Dunne developed

2600-430: The building required five years to complete, at a cost of more than 1.2 million pounds. The building is somewhat oddly shaped, forming a trapezoid in order to maximise the use of the irregularly shaped plot of land on which it was built: its four distinctive domes were designed as a decorative means of disguising the shape. It has around 1,100 rooms on seven floors. After 1964 the building continued to be used, under

2665-433: The centre of gravity provided longitudinal stability in the same way as a conventional tailplane set at lower incidence than the wings. Camber increased outwards. Simple, near parallel, pairs of interplane struts joined the spars. Fixed side curtains between upper and lower wing tips helped to control sideways airflow and provided additional directional ( yaw ) stability. Wing tip elevons were used for control, operated by

Dunne D.8 - Misplaced Pages Continue

2730-787: The dissolution of the Board of Ordnance, the War Office moved into the Board's former offices in Cumberland House , Pall Mall . Over the ensuing years it expanded into adjacent properties on Pall Mall before it was relocated to purpose-built accommodation, in what is now known as the Old War Office Building, in 1906. Between 1906 and its abolition in 1964 the War Office was based in a large neo-Baroque building designed by William Young , completed during 1906, and located on Horse Guards Avenue at its junction with Whitehall in Central London. The construction of

2795-667: The establishment of the Colonial Office in 1854). From 1824, the British Empire (excepting India , which was administered separately by the East India Company and then the India Office ) was divided by the War and Colonial Office into the following administrative departments: NORTH AMERICA WEST INDIES MEDITERRANEAN AND AFRICA EASTERN COLONIES The War Office, after 1854 and until

2860-404: The first being developed by the pioneer aviator J. W. Dunne . Sweeping the wing leading edge back, either as a swept wing or delta wing , and reducing the angle of incidence of the outer wing section allows the outer wing to act like a conventional tailplane stabiliser. If this is done progressively along the span of the outer section, it is called tip washout . Dunne achieved it by giving

2925-535: The first practical tailless aeroplane. The later D.8 was license-built and sold commercially by W. Starling Burgess in America as the Burgess-Dunne. He also returned to his monoplane. The D.6 of 1911 was a pusher type high-wing monoplane which also featured pronounced anhedral or droop to the wing tips. The control surfaces now also acted as rudders. Many of Dunne's ideas on stability remain valid, and he

2990-419: The government of Stanley Baldwin appointed a Minister for Co-ordination of Defence, who was not part of the War Office. When Winston Churchill became Prime Minister in 1940, he bypassed the War Office altogether, and appointed himself Minister of Defence (though there was, curiously, no ministry of defence until 1947). Clement Attlee continued this arrangement when he came to power in 1945, but appointed

3055-448: The jet age that this reputation was widely accepted to be undeserved. The solution usually adopted is to provide large elevator and/or elevon surfaces on the wing trailing edge. Unless the wing is highly swept, these must generate large control forces, as their distance from the aerodynamic center is small and the moments less. Thus a tailless type may experience higher drag during pitching manoeuvres than its conventional equivalent. In

3120-496: The job of Secretary remained occupied by a minister of the second rank (although he was occasionally part of the Cabinet after 1794). Many of his responsibilities were transferred to the Secretary of State for War after the creation of that more senior post in 1794 (though the latter was also responsible for Britain's colonies from 1801, and renamed Secretary of State for War and the Colonies , an arrangement which only ceased with

3185-499: The name The Old War Office, by the Ministry of Defence . On 1 June 2007 the building, other than the steps that give access to it, was designated as a protected site for the purposes of Section 128 of the Serious Organised Crime and Police Act 2005 . The effect was to make it a specific criminal offence for a person to trespass on the building. In August 2013 it was announced that the building would be sold on

3250-632: The office of Secretary at War was abolished altogether in 1863. In 1855, the Board of Ordnance was abolished as a result of its perceived poor performance during the Crimean War . This powerful independent body, dating from the 15th century, had been directed by the Master-General of the Ordnance , usually a very senior military officer who (unlike the Secretary at War) was often a member of

3315-624: The open market, with a goal of realising offers above 100 million pounds. On 13 December 2014 the Ministry of Defence confirmed that the building would be sold to the Hinduja Group for an undisclosed amount. The building was sold on 1 March 2016 for more than 350 million pounds, on a 250-year lease, to the Hinduja Group and OHL Developments for conversion to a luxury hotel and residential apartments. Hinduja and Raffles plan to open

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3380-409: The revised D.8 it was a Gnome powered two-seater, but it showed significant differences both aerodynamically and structurally. It combined the double upper wing elevons into a single surface and had very rounded rear wingtips. The fuselage was modified and built around steel tubes rather than wood. The interplane struts were streamlined steel tubes. It also had a simplified undercarriage. Dunne obtained

3445-421: The stabiliser can be removed and the drag reduced. A tailless aeroplane has no separate horizontal stabilizer. Because of this the aerodynamic center of an ordinary wing would lie ahead of the aircraft's center of gravity, creating instability in pitch . Some other method must be used to move the aerodynamic center backward and make the aircraft stable . There are two main ways for the designer to achieve this,

3510-705: The tailless delta configuration, and became one of the most widely produced of all Western jet aircraft. By contrast the Soviet Union's equivalent widely produced delta-winged fighter, the Mikoyan-Gurevich MiG-21 , does have a tail stabiliser. In the 1950s, the Convair F2Y Sea Dart prototype became the only seaplane to exceed the speed of sound. Convair built several other successful tailless delta types. The Anglo-French Concorde Supersonic transport , and its Soviet counterpart,

3575-597: The theory of the stable aerofoil. The designer Alexander Lippisch produced his first tailless design, the Delta I, in 1931. He went on to build a series of ever-more sophisticated designs, and at the end of the Second World War was taken to America to continue his work . During the Second World War , Lippisch worked for the German designer Willy Messerschmitt on the first tailless aircraft to go into production,

3640-434: The trailing edge of each wing tip acted as combined aileron and elevator. Dunne had an advanced qualitative appreciation of the aerodynamic principles involved, even understanding how negative lift at the wing tips, combined with steep downward-angled anhedral, enhanced directional stability. Although originally conceived as a monoplane , Dunne's initial designs for the Army were required to be biplanes , typically featuring

3705-649: The upper wings carried a pair of elevons, nearly doubling the control surface area. The maiden flight of the first D.8, fitted with a Green engine, took place at Eastchurch in June 1912. It was present at the Larkhill Military trial in August 1912, though it did not take part in the competition. Despite the two handed arrangement of the D.8's controls, the one-handed Capt. A. D. Carden gained his Royal Aero Club Aviator's Certificate on it in June 1912. In 1913

3770-488: The wing upper surface a conical curvature. In level flight the aircraft should be trimmed so that the tips do not contribute any lift: they may even need to provide a small downthrust. This reduces the overall efficiency of the wing, but for many designs – especially for high speeds – this is outweighed by the reductions in drag, weight and cost over a conventional stabiliser. The long wing span also reduces manoeuvrability, and for this reason Dunne's design

3835-430: Was later replaced by an 80 hp (60 kW) 7-cylinder Gnome rotary engine . This engine also powered the second aircraft, which was a two-seater with the pilot placed just ahead of the wing leading edge and the passenger (who had dual control) at the trailing edge. There were now control surfaces on both upper and lower wings, the side curtains having the rear corners cut off at an angle to allow them to move. Each of

3900-638: Was only remedied in 1904, when the job of Commander-in-Chief was abolished, and replaced with that of the Chief of the General Staff , which was replaced by the job of Chief of the Imperial General Staff in 1908. An Army Council was created with a format similar to that of the Board of Admiralty , directed by the Secretary of State for War, and an Imperial General Staff was established to coordinate Army administration. The creation of

3965-427: Was possibly one of the first aircraft ever to break the sound barrier – it did so during a shallow dive, and the sonic boom was heard by several witnesses. All three built were lost in fatal crashes. The DINFIA IA 38 was a 1960s Argentine four-engine experimental tailless transport aircraft , designed under the direction of Reimar Horten and based on the German Horten H.VIII project and built by

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4030-419: Was rejected by the British Army. An alternative is the use of low or null pitching moment airfoils , seen for example in the Horten series of sailplanes and fighters. These use an unusual wing aerofoil section with reflex or reverse camber on the rear or all of the wing. With reflex camber the flatter side of the wing is on top, and the strongly curved side is on the bottom, so the front section presents

4095-411: Was sold on 1 March 2016 by HM Government for more than £ 350 million, on a 250 year lease for conversion into a luxury hotel and residential apartments. Prior to 1855, 'War Office' signified the office of the Secretary at War . In the 17th and 18th centuries, a number of independent offices and individuals were responsible for various aspects of Army administration. The most important were

4160-432: Was usually a member of the House of Commons, routinely presented the House with the Army Estimates, and occasionally spoke on other military matters as required. In symbolic terms, he was seen as signifying parliamentary control over the Army. Issues of strategic policy during wartime were managed by the Northern and Southern Departments (the predecessors of today's Foreign Office and Home Office ). From 1704 to 1855,

4225-473: Was vacant for several periods, which left the Secretary at War answering directly to the Sovereign; and thereafter, even when the office of Commander-in-Chief was restored on a more permanent basis, the Secretary at War retained his independence. The department of the Secretary at War was referred to as the 'Warr Office' (sic) from as early as 1694; its foundation has traditionally been ascribed to William Blathwayt , who had accompanied King William III during

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