Biplane
A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While a biplane wing structure has a structural advantage over a monoplane, it produces more drag than a similar unbraced or cantilever monoplane wing. Improved structural techniques, better materials and the quest for greater speed made the biplane configuration obsolete for most purposes by the late 1930s. Biplanes offer several advantages over conventional cantilever monoplane designs: they permit lighter wing structures, low wing loading and smaller span for a given wing area. However, interference between the airflow over each wing increases drag and biplanes need extensive bracing, which causes additional drag. Biplanes are distinguished from tandem wing arrangements, where the wings are placed forward and aft, instead of above and below; the term is occasionally used in biology, to describe the wings of some flying animals.
In a biplane aircraft, two wings are placed one above the other. Each provides part of the lift, although they are not able to produce twice as much lift as a single wing of similar size and shape because the upper and the lower are working on nearly the same portion of the atmosphere and thus interfere with each other's behaviour. For example, in a wing of aspect ratio 6, a wing separation distance of one chord length, the biplane configuration will only produce about 20 percent more lift than a single wing of the same planform; the lower wing is attached to the fuselage, while the upper wing is raised above the fuselage with an arrangement of cabane struts, although other arrangements have been used. Either or both of the main wings can support ailerons, while flaps are more positioned on the lower wing. Bracing is nearly always added between the upper and lower wings, in the form of wires and/or slender interplane struts positioned symmetrically on either side of the fuselage; the primary advantage of the biplane over a monoplane is to combine great stiffness with light weight.
Stiffness requires structural depth and, where early monoplanes had to have this added with complicated extra bracing, the box kite or biplane has a deep structure and is therefore easier to make both light and strong. A braced monoplane wing must support itself while the two wings of a biplane help to stiffen each other; the biplane is therefore inherently stiffer than the monoplane. The structural forces in the spars of a biplane wing tend to be lower, so the wing can use less material to obtain the same overall strength and is therefore much lighter. A disadvantage of the biplane was the need for extra struts to space the wings apart, although the bracing required by early monoplanes reduced this disadvantage; the low power supplied by the engines available in the first years of aviation meant that aeroplanes could only fly slowly. This required an lower stalling speed, which in turn required a low wing loading, combining both large wing area with light weight. A biplane wing of a given span and chord has twice the area of a monoplane the same size and so can fly more or for a given flight speed can lift more weight.
Alternatively, a biplane wing of the same area as a monoplane has lower span and chord, reducing the structural forces and allowing it to be lighter. Biplanes suffer aerodynamic interference between the two planes; this means that a biplane does not in practice obtain twice the lift of the similarly-sized monoplane. The farther apart the wings are spaced the less the interference, but the spacing struts must be longer. Given the low speed and power of early aircraft, the drag penalty of the wires and struts and the mutual interference of airflows were minor and acceptable factors; as engine power rose after World War One, the thick-winged cantilever monoplane became practicable and, with its inherently lower drag and higher speed, from around 1918 it began to replace the biplane in most fields of aviation. The smaller biplane wing allows greater maneuverability. During World War One, this further enhanced the dominance of the biplane and, despite the need for speed, military aircraft were among the last to abandon the biplane form.
Specialist sports aerobatic biplanes are still made. Biplanes were designed with the wings positioned directly one above the other. Moving the upper wing forward relative to the lower one is called positive stagger or, more simply stagger, it can help increase lift and reduce drag by reducing the aerodynamic interference effects between the two wings, makes access to the cockpit easier. Many biplanes have staggered wings. Common examples from the 1930s include the de Havilland Tiger Moth, Bücker Bü 131 Jungmann and Travel Air 2000, it is possible to place the lower wing's leading edge ahead of the upper wing, giving negative stagger. This is done in a given design for practical engineering reasons. Examples of negative stagger include Breguet 14 and Beechcraft Staggerwing. However, positive stagger is more common; the space enclosed by a set of interplane struts is called a bay, hence a biplane or triplane with one set of such struts connecting the wings on each side of the aircraft is a single-bay biplane.
This provided sufficient strength for smaller aircraft such as the First World War-era Fokker D. VII fighter and the Second World War de Havilland Tiger Moth basic trainer; the larger two-seat Curtiss JN-4 Jenny is a two bay biplane, the extra bay being necessary as overlong bays are prone to flexing and can fail. The SPAD S. XIII fighter, while appearing to be a two bay bip
Royal Flying Corps
The Royal Flying Corps was the air arm of the British Army before and during the First World War, until it merged with the Royal Naval Air Service on 1 April 1918 to form the Royal Air Force. During the early part of the war, the RFC supported the British Army by artillery co-operation and photographic reconnaissance; this work led RFC pilots into aerial battles with German pilots and in the war included the strafing of enemy infantry and emplacements, the bombing of German military airfields and the strategic bombing of German industrial and transport facilities. At the start of World War I the RFC, commanded by Brigadier-General Sir David Henderson, consisted of five squadrons – one observation balloon squadron and four aeroplane squadrons; these were first used for aerial spotting on 13 September 1914 but only became efficient when they perfected the use of wireless communication at Aubers Ridge on 9 May 1915. Aerial photography again only became effective the next year. By 1918, photographic images could be taken from 15,000 feet and were interpreted by over 3,000 personnel.
Parachutes were not available to pilots of heavier-than-air craft in the RFC – nor were they used by the RAF during the First World War – although the Calthrop Guardian Angel parachute was adopted just as the war ended. By this time parachutes had been used by balloonists for three years. On 17 August 1917, South African General Jan Smuts presented a report to the War Council on the future of air power; because of its potential for the'devastation of enemy lands and the destruction of industrial and populous centres on a vast scale', he recommended a new air service be formed that would be on a level with the Army and Royal Navy. The formation of the new service would make the under-used men and machines of the Royal Naval Air Service available for action on the Western Front and end the inter-service rivalries that at times had adversely affected aircraft procurement. On 1 April 1918, the RFC and the RNAS were amalgamated to form a new service, the Royal Air Force, under the control of the new Air Ministry.
After starting in 1914 with some 2,073 personnel, by the start of 1919 the RAF had 4,000 combat aircraft and 114,000 personnel in some 150 squadrons. With the growing recognition of the potential for aircraft as a cost-effective method of reconnaissance and artillery observation, the Committee of Imperial Defence established a sub-committee to examine the question of military aviation in November 1911. On 28 February 1912 the sub-committee reported its findings which recommended that a flying corps be formed and that it consist of a naval wing, a military wing, a central flying school and an aircraft factory; the recommendations of the committee were accepted and on 13 April 1912 King George V signed a royal warrant establishing the Royal Flying Corps. The Air Battalion of the Royal Engineers became the Military Wing of the Royal Flying Corps a month on 13 May; the Flying Corps' initial allowed strength was 133 officers, by the end of that year it had 12 manned balloons and 36 aeroplanes. The RFC came under the responsibility of Brigadier-General Henderson, the Director of Military Training, had separate branches for the Army and the Navy.
Major Sykes commanded the Military Commander C R Samson commanded the Naval Wing. The Royal Navy however, with different priorities to that of the Army and wishing to retain greater control over its aircraft, formally separated its branch and renamed it the Royal Naval Air Service on 1 July 1914, although a combined central flying school was retained; the RFC's motto was Per ardua ad astra. This remains the motto of other Commonwealth air forces; the RFC's first fatal crash was on 5 July 1912 near Stonehenge on Salisbury Plain. Killing Captain Eustace B. Loraine and his observer, Staff Sergeant R. H. V. Wilson, flying from Larkhill Aerodrome. An order was issued after the crash stating "Flying will continue this evening as usual", thus beginning a tradition. In August 1912 RFC Lieutenant Wilfred Parke RN became the first aviator to be observed to recover from an accidental spin when the Avro G cabin biplane, with which he had just broken a world endurance record, entered a spin at 700 feet above ground level at Larkhill.
Four months on 11 December 1912 Parke was killed when the Handley Page monoplane in which he was flying from Hendon to Oxford crashed. Aircraft used during the war by the RFC included: Airco DH 2, DH 4, DH 5, DH 6, DH 9 Armstrong-Whitworth F. K.8 Avro 504 Bristol's Bristol Scout single-seat fighter, F2A and F2B Fighter two-seaters Handley Page O/400 Martinsyde G.100 Morane-Saulnier Bullet Biplane Parasol Nieuport Scout 17, 24, 27 Royal Aircraft Factory B. E.2a, B. E.2b, B. E.2c, B. E.2e, B. E.12, F. E.2b, F. E.8, R. E.8, S. E5a Sopwith Aviation Company 1½ Strutter, Triplane, Dolphin SPAD S. VII Vickers FB5 On its inception in 1912 the Royal Flying Corps consisted of a Military and a Naval Wing, with the Military Wing consisting of three squadrons each commanded by a major; the Naval Wing, with fewer pilots and aircraft than the Military Wing, did not organise itself into squadrons until 1914. By November 1914 the Royal Flying Corps taking the loss of the Naval Wing into account, had expanded sufficiently to warrant the creation of wings consisting of two or more squadrons.
These wings were commanded by lieutenant-colonels. In October 1915 the Corps had undergone further expansion which justified the creation of brigades, each commanded by a brigadier-general. Further expansion led to the creation of divisions, with the Training Division being established in August 1917 and R
Aircraft fabric covering
Aircraft fabric covering is a term used for both the material used and the process of covering aircraft open structures. It is used for reinforcing closed plywood structures, the de Havilland Mosquito being an example of this technique, on the pioneering all-wood monocoque fuselages of certain World War I German aircraft like the LFG Roland C. II, in its wrapped Wickelrumpf plywood strip and fabric covering. Early aircraft used organic materials such as cotton and cellulose nitrate dope, modern fabric-covered designs use synthetic materials such as Dacron and butyrate dope for adhesive, this method is used in the restoration of older types that were covered using traditional methods; the purposes of the fabric covering of an aircraft are: To provide a light airproof skin for lifting and control surfaces. To provide structural strength to otherwise weak structures. To cover other non-lifting parts of an aircraft to reduce drag, sometimes forming a fairing. To protect the structure from the elements.
Pioneering aviators such as George Cayley and Otto Lilienthal used cotton-covered flying surfaces for their manned glider designs. The Wright brothers used cotton to cover their Wright Flyer. Other early aircraft used a variety of fabrics and linen being used; some early aircraft, such as A. V. Roe's first machines used paper as a covering material; until the development of cellulose based dope in 1911 a variety of methods of finishing the fabric were used. The most popular was the use of rubberised fabrics such as those manufactured by the "Continental" company. Other methods included the use of sago starch; the advent of cellulose dopes such as "Emaillite" was a major step forward in the production of practical aircraft, producing a surface that remained taut The air battles of World War I were fought with fabric-covered biplanes that were vulnerable to fire due to the flammable properties of the cloth covering and nitrocellulose dope. National insignia painted on the fabric were cut from downed aircraft and used as war trophies.
The German aircraft designer Hugo Junkers is considered one of the pioneers of metal aircraft. The flammable mixture of fabric and hydrogen gas was a factor in the demise of the Hindenburg airship. By the World War II era many aircraft designs were using metal monocoque structures due to their higher operating airspeeds, although fabric-covered control surfaces were still used on early mark Spitfires and other types; the Hawker Hurricane had a fabric covered fuselage, they had fabric covered wings until 1939. Many transports and trainers still used fabric, although the flammable nitrate dope was replaced with butyrate dope instead, which burns less readily; the Mosquito is an example of a fabric-covered plywood aircraft. The Vickers Wellington used fabric over a geodesic airframe which offered good combat damage resistance. An interesting case of ingenuity under wartime adversity was the Colditz Cock glider; this homebuilt aircraft, intended as a means of escape, employed prison bedding as its covering material.
With the development of modern synthetic materials following World War II, cotton fabrics were replaced in civil aircraft applications by polyethylene terephthalate, known by the trade-name Dacron or Ceconite. This new fabric could be glued to the airframe instead of sewn and heat-shrunk to fit. Grade A cotton would last six to seven years when the aircraft was stored outside, whereas Ceconite, which does not rot like cotton, can last over 20 years. Early attempts to use these modern fabrics with butyrate dope proved that the dope did not adhere at all and peeled off in sheets. Nitrate dope was resurrected as the initial system of choice instead, although it was supplanted by new materials too. One fabric system, developed by Ray Stits in the USA and FAA-approved in 1965, is marketed under the brand name Poly-Fiber; this uses three weights of Dacron fabric sold as by the brand name Ceconite, plus fabric glue for attaching to the airframe, fabric preparation sealer resin and paint. This system instead uses vinyl-based chemicals.
Ceconite 101 is a certified 3.5 oz/yd ² fabric. There is an uncertified light Ceconite of 1.87 oz/yd² intended for ultralight aircraft. This method requires physical attachment of the fabric to the airframe in the form of rib-stitching, rivets or capstrips, which are usually covered with fabric tapes. In addition to Poly-Fiber, a number of other companies produce covering processes for certified and homebuilt aircraft. Randolph Products and Certified Coatings Products both make butyrate and nitrate-based dopes for use with Dacron fabric. Superflite and Air-Tech systems use a similar fabric, but the finishes are polyurethane-based products with flex agents added; these finishes produce high gloss results. Falconar Avia of Edmonton, Canada developed the Hipec system in 1964 for use with Dacron fabric, it uses a special Hipec Sun Barrier that adheres fabric directly to the aircraft structure in one step, eliminating the need for the riveting, rib-stitching and taping used in traditional fabric processes.
The final paint is applied over the sun barrier to complete the process. Newer systems were developed and distributed by Stewart Systems of Cashmere and Blue River; these two systems use the same certified dacron materials as other systems, but do not use high volatile organic compounds, using water as a carrier i
Morane-Saulnier H
The Morane-Saulnier H was an early aircraft first flown in France in the months preceding the First World War. German versions, both licensed and copied, were armed with forward-firing machine guns and became the first single-seat fighter aircraft so armed; the French Army ordered a batch of 26 aircraft under the designation MoS.1, the British Royal Flying Corps acquired a small number, these latter machines purchased from Grahame-White, manufacturing the type in the UK under licence. During the second international aero meet, held at Wiener Neustadt in June 1913, Roland Garros won the precision landing prize in a Type H; that same year, A Morane-Saulnier H was used to complete the first non-stop flight across the Mediterranean, from Fréjus in the south of France to Bizerte in Tunisia. French-built machines saw limited service in the opening stages of World War I, with pilots carrying out reconnaissance missions and engaging in aerial combat using revolvers and carbines. A German-built copy entered production as the Fokker M.5 in 1913: it featured a longer fuselage, framed in steel tube rather than wood, a comma shaped rudder, a redesigned undercarriage integrated with the under-wing bracing pylons.
When armed in 1915 with a synchronised machine gun it became the first of the Fokker "Eindecker" monoplane fighters. The type was produced under licence in Germany by the Pfalz Flugzeugwerke: during the war the company built armed versions as the E. I, E. II, E. IV, E. V, E. VI, with powerful engines. Like the better known Fokkers, with which they were confused by Allied airmen, these were armed with a single, synchronised lMG 08 machine gun. A Type H is preserved at the Musée de l'Air et de l'Espace in Le Bourget and another at the Fantasy of Flight in Florida. Several replicas are in museums or flying. Type G two seater Type H single seater Type L parasol monoplane Type M armoured single seater Type O racing monoplane developed from H, two built including one for Roland Garros, fitted with wheels and floatsMoS.1 Official designation for Type H MoS.2 Official designation for Type G MoS.3 Official designation for Type L MoS.13 Official designation for Type M E. I - with Oberursel U.0 rotary engine E.
II - with Oberursel U. I rotary engine E. IV - with Oberursel U. III rotary engine E. V - with Mercedes D. I water-cooled, inline engine E. VI - with Oberursel U. I engine, lengthened fuselage, enlarged tail fin and reduced bracing FranceAéronautique Militaire Austria-HungaryAustro-Hungarian Navy - BelgiumBelgian Air Force DenmarkArmy Flying Service - 2 examples. GermanyLuftstreitkräfte - PortugalPortuguese Air Force - one aircraft. United KingdomRoyal Flying Corps RussiaImperial Russian Air Service SwitzerlandSwiss Air Force - two aircraft Data from flugzeuginfo.netGeneral characteristics Crew: One pilot Length: 5.84 m Wingspan: 9.12 m Height: 2.26 m Empty weight: 188 kg Gross weight: 444 kg Powerplant: 1 × Le Rhône 9C, 60 kW Performance Maximum speed: 120 km/h Range: 177 km Service ceiling: 1,000 m Armament Brannon, D. Edgar. Fokker Eindecker in Action. Carrolton, Texas: Squadron/Signal Publication. Davilla, Dr. James J.. French Aircraft of the First World War. Mountain View, CA: Flying Machines Press.
ISBN 978-1891268090. Grosz, P. M.. Pfalz E. I–E. VI. Berkhamsted, Hertfordshire: Albatros Publications. Hartmann, Gérard. "L'incroyable Morane-Saulnier hydro". La Coupe Schneider et hydravions anciens/Dossiers historiques moteurs. Retrieved 2008-11-07. Herris, Jack. Pflaz Aircraft of World War I. Boulder, Colorado: Flying Machines Press. ISBN 1-891268-15-5; the Illustrated Encyclopedia of Aircraft. London: Aerospace Publishing. "Morane-Saulnier Type H". Flugzeuginfo.net. Retrieved 2008-11-07. Taylor, Michael J. H.. Jane's Encyclopedia of Aviation. London: Studio Editions. Angelucci, Enzo; the Rand McNally encyclopedia of military aircraft, 1914-1980. The Military Press. P. 20. ISBN 0-517-41021 4
Fixed-wing aircraft
A fixed-wing aircraft is a flying machine, such as an airplane or aeroplane, capable of flight using wings that generate lift caused by the aircraft's forward airspeed and the shape of the wings. Fixed-wing aircraft are distinct from rotary-wing aircraft, ornithopters; the wings of a fixed-wing aircraft are not rigid. Gliding fixed-wing aircraft, including free-flying gliders of various kinds and tethered kites, can use moving air to gain altitude. Powered fixed-wing aircraft that gain forward thrust from an engine include powered paragliders, powered hang gliders and some ground effect vehicles. Most fixed-wing aircraft are flown by a pilot on board the craft, but some are designed to be unmanned and controlled either remotely or autonomously. Kites were used 2,800 years ago in China, where materials ideal for kite building were available; some authors hold that leaf kites were being flown much earlier in what is now Sulawesi, based on their interpretation of cave paintings on Muna Island off Sulawesi.
By at least 549 AD paper kites were being flown, as it was recorded in that year a paper kite was used as a message for a rescue mission. Ancient and medieval Chinese sources list other uses of kites for measuring distances, testing the wind, lifting men and communication for military operations. Stories of kites were brought to Europe by Marco Polo towards the end of the 13th century, kites were brought back by sailors from Japan and Malaysia in the 16th and 17th centuries. Although they were regarded as mere curiosities, by the 18th and 19th centuries kites were being used as vehicles for scientific research. Around 400 BC in Greece, Archytas was reputed to have designed and built the first artificial, self-propelled flying device, a bird-shaped model propelled by a jet of what was steam, said to have flown some 200 m; this machine may have been suspended for its flight. One of the earliest purported attempts with gliders was by the 11th-century monk Eilmer of Malmesbury, which ended in failure.
A 17th-century account states that the 9th-century poet Abbas Ibn Firnas made a similar attempt, though no earlier sources record this event. In 1799, Sir George Cayley set forth the concept of the modern aeroplane as a fixed-wing flying machine with separate systems for lift and control. Cayley was building and flying models of fixed-wing aircraft as early as 1803, he built a successful passenger-carrying glider in 1853. In 1856, Frenchman Jean-Marie Le Bris made the first powered flight, by having his glider "L'Albatros artificiel" pulled by a horse on a beach. In 1884, the American John J. Montgomery made controlled flights in a glider as a part of a series of gliders built between 1883–1886. Other aviators who made similar flights at that time were Otto Lilienthal, Percy Pilcher, protégés of Octave Chanute. In the 1890s, Lawrence Hargrave conducted research on wing structures and developed a box kite that lifted the weight of a man, his box kite designs were adopted. Although he developed a type of rotary aircraft engine, he did not create and fly a powered fixed-wing aircraft.
Sir Hiram Maxim built a craft that weighed 3.5 tons, with a 110-foot wingspan, powered by two 360-horsepower steam engines driving two propellers. In 1894, his machine was tested with overhead rails to prevent it from rising; the test showed. The craft was uncontrollable, which Maxim, it is presumed, because he subsequently abandoned work on it; the Wright brothers' flights in 1903 with their Flyer I are recognized by the Fédération Aéronautique Internationale, the standard setting and record-keeping body for aeronautics, as "the first sustained and controlled heavier-than-air powered flight". By 1905, the Wright Flyer III was capable of controllable, stable flight for substantial periods. In 1906, Brazilian inventor Alberto Santos Dumont designed and piloted an aircraft that set the first world record recognized by the Aéro-Club de France by flying the 14 bis 220 metres in less than 22 seconds; the flight was certified by the FAI. This was the first controlled flight, to be recognised, by a plane able to take off under its own power alone without any auxiliary machine such as a catapult.
The Bleriot VIII design of 1908 was an early aircraft design that had the modern monoplane tractor configuration. It had movable tail surfaces controlling both yaw and pitch, a form of roll control supplied either by wing warping or by ailerons and controlled by its pilot with a joystick and rudder bar, it was an important predecessor of his Bleriot XI Channel-crossing aircraft of the summer of 1909. World War I served as a testbed for the use of the aircraft as a weapon. Aircraft demonstrated their potential as mobile observation platforms proved themselves to be machines of war capable of causing casualties to the enemy; the earliest known aerial victory with a synchronised machine gun-armed fighter aircraft occurred in 1915, by German Luftstreitkräfte Leutnant Kurt Wintgens. Fighter aces appeared. Following WWI, aircraft technology continued to develop. Alcock and Brown crossed the Atlantic non-stop for the first time in 1919; the first commercial flights took place between the United States and Canada in 1919.
The so-called Golden Age of Aviation occurred between the two World War
Delta wing
The delta wing is a wing shaped in the form of a triangle. It is named for its similarity in shape to the Greek uppercase letter delta. Although long studied, it did not find significant applications until the jet age, when it proved suitable for high-speed subsonic and supersonic flight. At the other end of the speed scale, the Rogallo flexible wing proved a practical design for the hang glider and other ultralight aircraft; the delta form brings aerodynamic characteristics. Many design variations have evolved over the years and without additional stabilising surfaces; the long root chord of the delta wing, minimal structure outboard, make it structurally efficient. It can be built stronger, stiffer and at the same time lighter than a swept wing of equivalent lifting capability; because of this it is easy and inexpensive to build – a substantial factor in the success of the MiG-21 and Mirage aircraft. Its long root chord allows a deeper structure for a given aerofoil section, providing more internal volume for fuel and other storage without a significant increase in drag.
However on supersonic designs the opportunity is taken to use a thinner aerofoil instead, in order to reduce drag. Pure delta wings exhibit flow separation at high angles of attack and high drag at low speeds. At low speeds a delta wing requires a high angle of attack to maintain lift. A slender delta creates a characteristic vortex pattern over the upper surface; some types with intermediate sweep have been given retractable "moustaches" or fixed leading-edge root extensions to encourage vortex formation. As the angle of attack increases, the leading edge of the wing generates a vortex which energises the flow on the upper surface of the wing, delaying flow separation, giving the delta a high stall angle. A normal wing built for high speed use has undesirable characteristics at low speeds, but in this regime the delta changes over to a mode of lift based on the vortex it generates, a mode where it has smooth and stable flight characteristics; the vortex lift comes at the cost of increased drag, so more powerful engines are needed to maintain low speed or high angle-of-attack flight.
With a large enough angle of rearward sweep, in the transonic to low supersonic speed range the wing's leading edge remains behind the shock wave boundary or shock cone created by the leading edge root. This allows air below the leading edge to flow out, up and around it back inwards creating a sideways flow pattern; the lift distribution and other aerodynamic characteristics are influenced by this sideways flow. The rearward sweep angle lowers the airspeed normal to the leading edge of the wing, thereby allowing the aircraft to fly at high subsonic, transonic, or supersonic speed, while the subsonic lifting characteristics of the airflow over the wing are maintained. Within this flight regime, drooping the leading edge within the shock cone increases lift but not drag; such conical leading edge droop was introduced on the production Convair F-102A Delta Dagger at the same time that the prototype design was reworked to include area-ruling. It appeared on Convair's next two deltas, the F-106 Delta Dart and B-58 Hustler.
At high supersonic speeds the shock cone from the leading edge root angles further back to lie along the wing surface behind the leading edge. It is no longer possible for the sideways flow to occur and the aerodynamic characteristics change considerably, it is in this flight regime that the waverider technique, as used on the North American XB-70 Valkyrie, becomes practicable. Here, a shock body beneath the wing creates an attached shockwave and the high pressure associated with the wave provides significant lift without increasing drag. Variants of the delta delta wing plan offer improvements to the basic configuration. Canard delta – Many modern fighter aircraft, such as the JAS 39 Gripen, the Eurofighter Typhoon and the Dassault Rafale use a combination of canards and a delta wing. Tailed delta -- adds a conventional tailplane. Common on Soviet types such as the Mikoyan-Gurevich MiG-21. Cropped delta – tip is cut off; this helps reduce wingtip flow separation at high angles of attack. Most deltas are cropped to at least some degree.
In the compound delta, double delta or cranked arrow, the leading edge is not straight. The inboard section has increased sweepback, creating a controlled high-lift vortex without the need for a foreplane. Examples include the Saab Draken fighter, the prototype General Dynamics F-16XL and the High Speed Civil Transport study; the ogee delta used on the Anglo-French Concorde Mach 2 airliner is similar, but with the two sections and cropped wingtip merged into a smooth ogee curve. Like other tailless aircraft, the tailless delta wing is not suited to high wing loadings and requires a large wing area for a given aircraft weight; the most efficient aerofoils are unstable in pitch and the tailless type must use a less efficient design and therefore a bigger wing. Techniques used include: Using a less efficient aerofoil, inherently stable, such as a symmetrical form with zero camber, or reflex camber near the trailing edge, Using the rear part of the wing as a lightly- or negatively-loaded horizontal stabiliser: Twisting the outer leading edge down to reduce the incidence of the wing tip, behind the main centre of lift.
This improves stall characteristics and can benefit supersonic cruise in other ways. Moving the centre of mass forwards and trimming the elevator to exert a balancing downforce. In the extreme, this reduces the craft's ability to pitch its nose up for landing. A conventiona
Etrich Taube
The Etrich Taube known by the names of the various manufacturers who build versions of the type, such as the Rumpler Taube, was a pre-World War I monoplane aircraft. It was the first military aeroplane to be mass-produced in Germany; the Taube was popular prior to the First World War, it was used by the air forces of Italy and Austria-Hungary. The Royal Flying Corps operated at least one Taube in 1912. On November 1, 1911, Giulio Gavotti, an Italian aviator, dropped the world's first aerial bomb from his Taube monoplane over the Ain Zara oasis in Libya. Once the war began, it proved inadequate as a warplane and was soon replaced by other designs; the Taube was designed in 1909 by Igo Etrich of Austria-Hungary, first flew in 1910. It was licensed for serial production by Lohner-Werke in Austria and by Edmund Rumpler in Germany, now called the Etrich-Rumpler-Taube. Rumpler soon changed the name to Rumpler-Taube, stopped paying royalties to Etrich, who subsequently abandoned his patent. Despite its name, the Taube's unique wing form was not modeled after a dove, but was copied from the seeds of Alsomitra macrocarpa, which can fly long distances from their parent tree.
Similar wing shapes were used by Karl Jatho and Frederick Handley Page. Etrich had tried to build a flying wing aircraft based on the Zanonia wing shape, but the more conventional Taube type, with tail surfaces, was much more successful. Etrich adopted the format of crosswind-capable main landing gear that Louis Blériot had used on his Blériot XI cross-channel monoplane for better ground handling; the wing has three spars and was braced by a cable-braced steel tube truss under each wing: at the outer end the uprights of this structure were lengthened to rise above the upper wing surfaces, to form kingposts to carry bracing and warping wires for the enlarged wingtips. A small landing wheel was sometimes mounted on the lower end of this kingpost, to protect it for landings and to help guard against ground loops. Taube-type aircraft from other manufacturers replaced the Bleriot type main gear with a simpler V-strut main gear design, omitted the underwing "bridge" structure to reduce drag. Like many contemporary aircraft monoplanes, the Taube used wing warping rather than ailerons for lateral control, warped the rear half of the stabilizer to function as the elevator.
Only the vertical, twinned triangular rudder surfaces were hinged. The design provided for stable flight, which made it suitable for observation. In addition, the translucent wings made it difficult for ground observers to detect a Taube at an altitude above 400 meters; the first hostile engagement was by an Italian Taube in 1911 in Libya, its pilot using pistols and dropping 2 kg grenades. The Taube was used for bombing in the Balkans in 1912–13, in late 1914 when German 3 kg bomblets and propaganda leaflets were dropped over Paris. Taube spotter planes detected the advancing Imperial Russian Army in East Prussia during the World War I Battle of Tannenberg. In civilian use, the Taube was used by pilots to win the Munich-Berlin Kathreiner prize. On 8 December 1911, Gino Linnekogel and Suvelick Johannisthal achieved a two-man endurance record for flying a Taube 4 hours and 35 minutes over Germany. While there were two Taube aircraft assigned to Imperial German units stationed at Qingdao, only one was available at the start of the war due to an accident.
The Rumpler Taube piloted by Lieutenant Gunther Plüschow had to face the attacking Japanese, who had with them a total of eight aircraft. On October 2, 1914, Plüschow's Taube attacked the Japanese warships with two small bombs, but failed to score any hits. On November 7, 1914, shortly before the fall of Qingdao, Plüschow was ordered to fly top secret documents to Shanghai, but was forced to make an emergency landing at Lianyungang in Jiangsu, where he was interned by a local Chinese force. Plüschow was rescued by local Chinese civilians under the direction of an American missionary, reached his destination at Shanghai with his top secret documents, after giving the engine to one of the Chinese civilians who rescued him. Poor rudder and lateral control made the Taube slow to turn; the aeroplane proved to be a easy target for the faster and more mobile Allied fighters of World War I, just six months into the war, the Taube had been removed from front line service to be used to train new pilots.
Many future German aces would learn to fly in a Rumpler Taube. Due to the lack of license fees, no less than 14 companies built a large number of variations of the initial design, making it difficult for historians to determine the exact manufacturer based on historical photographs. An incomplete list is shown below; the most common version was the Rumpler Taube with two seats. Albatros Taube Produced by Albatros Flugzeugwerke Albatros Doppeltaube Biplane version produced by Albatros Flugzeugwerke. Aviatik Taube Produced by Automobil und Aviatik AG firm. DFW Stahltaube Version with steel frame produced by Deutsche Flugzeug-Werke. Etrich Taube Produced by inventor Igo Etrich. Etrich-Rumpler-Taube Initial name of the "Rumpler Taube". Gotha Taube Produced by Gothaer Waggonfabrik as LE.1, LE.2 and LE.3 and designated A. I by the Idflieg. Harlan-Pfeil-Taube Halberstadt Taube III Produced by Halberstädter Flugzeugwerke. Jeannin Taube Version with steel tubing fuselage structure. Kondor Taube Produced by Kondor Flugzeugwerke.
RFG Taube Produced by Reise- und Industrieflug GmbH. Roland Taube Rumpler 4C Taube Produced by Edmund Rumpler's Rumpler Flugzeugwerke. Rumpler Delfin-Taube Version wit
