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35-452: Bohannon began construction of Pushy Galore in 1988 and first flew it in the early part of 1989, first entering it in a race in June 1989. The aircraft is of three-surface configuration, having a cantilever mid-wing , a single-seat enclosed cockpit under a bubble canopy , fixed main tricycle landing gear with a retractable nose wheel, a t-tail and a nose-mounted canard . It is powered by

70-473: A canard aircraft , to allow natural static pitch stability in normal flight, the foreplane must provide lift. Also, in order for the aircraft to have safe stall characteristics the foreplane must stall before the main wing, pitching the aircraft down and allowing the aircraft to recover. This means that a safety margin must be used on the main wing area so that its maximum lift coefficient and wing loading are never attained in practice. This in turn means that

105-408: A conventional aircraft this pitch trim force is applied by a tailplane . On many modern designs, the wing centre of pressure is normally aft of the centre of gravity, so the tailplane must exert a downward force. Any such negative lift generated by the tail must be compensated by additional lift from the main wing, thus increasing wing area, drag, and weight requirements. On a three-surface aircraft,

140-588: A conventional layout. Fokker V.8 Fokker V.8 was a five-winged aircraft built by Fokker for the Luftstreitkräfte during World War I. After the initial success of the Fokker Dr.I triplane , Anthony Fokker proposed a quintuplane, reasoning that if three wings were good, five would be even better. Reinhold Platz , chief engineer for Fokker, was at first shocked by the idea: further thought only strengthened this reaction. Nevertheless,

175-462: A minimum of total surface area to the slipstream; thus reducing surface drag for speed and fuel efficiency. Several reviews compare the Avanti's top speed and service ceiling to that of lower-end jet aircraft, and report significantly better fuel efficiency at cruise speed. Piaggio attributes this performance in part to the layout of the aircraft, claiming a 34% reduction in total wing area compared to

210-552: A modified McDonnell Douglas F-15 , the F-15 STOL/MTD , in 1988 but these designs were not followed up. In the Soviet Union a Sukhoi Su-27 modified with canard foreplanes flew in 1985 and derivatives of this design became the only military three-surface types to enter production. Also in 1979, Piaggio began design studies on a three-surface civil twin turboprop which, in collaboration with Learjet , would emerge as

245-592: A number of subsequent production variants including the naval Su-33 (Su-27K), some Su-30s, the Su-35 and the Su-37. The Chinese Shenyang J-15 also inherits the configuration of the Su-33. The McDonnell Douglas F-15 STOL/MTD was an F-15 airframe modified with canard foreplanes and thrust vectoring, designed to demonstrate these technologies for both STOL performance and high manoeuvrability. The three-surface configuration

280-591: A single rear-mounted engine in pusher configuration . The aircraft is made from welded steel tubing covered in molded carbon fiber . As required by the Formula One rules, its engine is a 100 hp (75 kW) Continental O-200A . Only one example was ever built. Bohannon entered the aircraft in the Reno Air Races in 1994, qualifying in third place in the Formula One class, with a speed of 236.153 mph (380.051 km/h). In 1995 Bohannon flew

315-564: A three-surface configuration, often in conjunction with thrust vectoring . This is typically intended to enhance control and manoeuvrability, especially at very high angles of attack beyond the stall point of the main wing. Some advanced combat manoeuvres such as Pugachev's Cobra and the Kulbit were first performed on Sukhoi three-surface aircraft. The experimental Grumman X-29 was of basic "tail-first" canard configuration, with unusual forward-swept wings and strakes extending rearwards from

350-429: Is claimed to reduce total aerodynamic surface area compared to the conventional and canard configurations, thus enabling drag and weight reductions. On most aircraft, the wing centre of pressure moves forward and backward according to flight conditions. If it does not align with the centre of gravity , a corrective or trim force must be applied to prevent the aircraft pitching and thus to maintain equilibrium. On

385-543: Is positioned ahead of the centre of gravity, so its lift moment acts in the same direction as any movement in pitch. If the aircraft is to be naturally stable, the foreplane's size, lift slope and moment arm must be chosen so that it does not overpower the stabilizing moment provided by the wing and tailplane. Stability constraints thus limit the foreplane's volume ratio (a measure of its effectiveness in trim and stability terms), which may in turn limit its ability to share pitch trim forces as described above. The minimum size of

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420-505: Is usually the largest, while the functions of the fore and aft planes may vary between types and may include lift, control and/or stability. In civil aircraft the three surface configuration may be used to give safe stalling characteristics and short takeoff and landing (STOL) performance. It is also claimed to allow minimizing the total wing surface area, reducing the accompanying skin drag. In combat aircraft this configuration may also be used to enhance maneuverability both before and beyond

455-564: The AirVenture Museum . Bohannon later went on to set many more time-to-climb records in his successor to Pushy Galore, the Bohannon B-1 . Data from AirVenture Museum General characteristics Performance Three-surface aircraft A three-surface aircraft or sometimes three-lifting-surface aircraft has a foreplane , a central wing and a tailplane . The central wing surface always provides lift and

490-621: The Peterson Katmai , entered production. A broadly similar approach is taken by the 1988 Eagle-XTS and its derivatives, the Eagle 150 series. Around 1979, military jet designers began studying three-surface configurations as a way to provide enhanced manoeuvrability and control, especially at low speeds and high angles of attack such as during takeoff and combat. In the United States the experimental Grumman X-29 flew in 1984 and

525-488: The Piaggio P.180 Avanti . This type first flew in 1986 and entered service in 1990, with production continuing today. In the Avanti, the three-surface configuration is claimed to significantly reduce wing size, weight and drag compared to the conventional equivalent. Two experimental aircraft adopting this configuration were subsequently built by Scaled Composites under the lead of Burt Rutan and flown in 1988. The Triumph

560-514: The FT-10 Cruisaire. It is possible to achieve such a soft stall with a pure canard design, but it is then difficult to control the pitching and oscillations can develop as the foreplane repeatedly lifts the nose, stalls and recovers. Also, care must be taken in the design that the turbulent wake from the stalled foreplane does not in itself disturb the airflow over the main wing sufficiently to cause significant loss of lift and cancel out

595-485: The aircraft to 9,000 m (29,528 ft) in 41 minutes and 35 seconds, setting class world time-to-climb, absolute altitude and altitude in horizontal flight records. In July 1996 at AirVenture in Oshkosh, Bohannon set a third FAI class time-to-climb record of 3,000 m (9,843 ft) in three minutes and eight seconds. After the climb records were set in 1996, Bohannon retired the aircraft and in 1998 donated it to

630-561: The aircraft to second place in the Formula One Gold championship race at Reno, Nevada . Bohannon also used the aircraft to set world time-to-climb records in the Fédération Aéronautique Internationale (FAI) C-1.A class. At AirVenture 1994 Bohannon set a new world time-to-climb record, climbing to 6,000 m (19,685 ft) in 12 minutes and 50 seconds. In January 1996, Bohannon climbed

665-431: The aircraft was built. Using some parts of the V.6 , Platz designed a machine with three wings at the extreme front of the aircraft and a pair of wings midway along the fuselage, the mid-fuselage biplane wings placed where their leading edges were virtually even with the aft end of the cockpit coaming. Balanced control surfaces were fitted to the upper wings, those at the front acting as conventional ailerons and those in

700-537: The equivalent two-surface aircraft, so reducing both weight and drag. Minimum area in cruise can be further reduced through the use of conventional high-lift devices such as flaps, allowing a three-surface design to have minimum surface area at all points in the flight envelope. Examples of reduced-area three-surface aircraft include the Piaggio P.180 Avanti , and the Scaled Composites Triumph and Catbird . These aircraft were designed to expose

735-567: The high angles of attack and accompanying dangers of stalling required by conventional STOL designs. The aircraft was evaluated by the US Army. Robertson's system was commercialised as the Wren 460 , a modified Cessna light aircraft. This in turn was later licensed and produced during the 1980s as the Peterson 260SE and with the foreplane modification only as the 230SE. In 2006 a ruggedised variant,

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770-468: The lifting wings of an aircraft is determined by: the weight of the aircraft, the force required to oppose the negative lift produced by the horizontal stabilizer, the targeted take off and landing speeds, and the coefficient of lift of the wings. Most modern aircraft use trailing edge flaps on the main wing to increase the wings lift coefficient during takeoff and landing; thus allowing the wing to be smaller than it would otherwise need to be. This may reduce

805-413: The main wing must be increased in size. On a three-surface aircraft, the tailplane acts as a conventional horizontal stabiliser . In the stall condition, even if the main wing is stalled the tailplane can provide a pitch-down moment and allow recovery. The wing may thus be used up to its maximum lift coefficient, an advantage that may translate into a reduction of its area and weight. A lifting foreplane

840-409: The main wing must be large enough to not only lift the aircraft's remaining weight at takeoff but also to provide adequate safety margin to prevent stalling. On a three-surface aircraft, neither of these handicaps is present and the main wing can be reduced in size, so also reducing weight and drag. It is claimed that the total area of all wing surfaces of a three-surface aircraft can be less than that of

875-410: The main wing roots. Movable flaps at the ends of the strakes effectively made it a three-surface design. The X-29 demonstrated exceptional high-angle of attack manoeuvrability. A more straightforward three-surface design is seen in several variants of the otherwise conventional Sukhoi Su-27 . Following the successful addition of canard foreplanes to a development aircraft, these were incorporated into

910-413: The negative pitching moment created by the trailing edge flaps. This, in turn, means that the main wing must be somewhat larger than it would otherwise have to be to balance the larger negative lift produced by the larger horizontal stabilizer. On a canard aircraft the foreplane can provide positive lift at takeoff, reducing some of the down force the rear stabilizer would otherwise have to create. However,

945-468: The nose-down pitching moment. In the three-surface design the third, tail surface does not stall and provides better controllability. In the 1950s James Robertson developed his experimental Skyshark. This was a broadly conventional design but with a variety of features, including a small canard foreplane, intended to give not only a safe stall but good Short takeoff and landing (STOL) performance. The foreplane allowed STOL performance to be achieved without

980-478: The outbreak of the First World War in 1914, the main wing with smaller rear tail surface had become the conventional configuration and few three surface types would be flown for many years. The Fokker V.8 of 1917 and Caproni Ca.60 Noviplano of 1921 were both failures. In 1920s George Fernic developed the idea of two lifting surfaces in tandem, together with a conventional tailplane. The small foreplane

1015-463: The pitch trim forces can be shared, as needed in flight, between the foreplane and tailplane. Equilibrium can be achieved with lift from the foreplane rather than downforce from the tailplane. Both effects, the reduced downforce and the extra lifting force, reduce the load on the main wing. The Piaggio P.180 Avanti has flaps on both its forward wing and main wing. Both flaps deploy in concert to maintain pitch neutrality for take-off and landing. On

1050-459: The rear working with the elevators . The pilot was seated just ahead of the biplane wings. Like the V.6, it was powered by a 120 hp (90 kW) water-cooled Mercedes engine. Fokker, who was his own test pilot, made two brief flights in October 1917, after which it was abandoned. The Fokker V.8 was powered by a 119 kW (160 hp) Mercedes engine. Platz regarded the aircraft as such

1085-437: The stall, often in conjunction with vectored thrust . An early designation used in 1911 was "three plane system". The Fernic designs of the 1920s were referred to as "tandem". While there are indeed two lifting wing surfaces in tandem, the tailplane forms a third horizontal surface. During the pioneer years of aviation a number of aircraft were flown with both fore and aft auxiliary surfaces. The issue of control vs. stability

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1120-438: The weight of the wing, and it always reduces the surface area of the wing. The reduction of surface area proportionately reduces skin drag at all speeds. A drawback of the use of trailing edge flaps is that they produce significant negative pitching moment when in use. In order to balance this pitching moment the horizontal stabilizer must be somewhat larger than it would otherwise be, so that it can produce enough force to balance

1155-521: Was a twin-turbofan very light jet aircraft designed for Beechcraft . Flight testing validated the targeted performance range. The Catbird was a single-engined propeller-driven aircraft, envisioned by Rutan as a replacement for the Beechcraft Bonanza . It holds the world record for speed over a closed circuit of 5,000 km (3,100 mi) without payload of 334.44 km/h (207.81 mph) set in 2014. Some advanced jet aircraft have

1190-418: Was highly loaded and as the angle of attack increased it was designed to stall first, causing the nose to drop and allowing the aircraft to recover safely without stalling the main wing. This "soft" stall provides a level of safety in the stall which is not usually present in conventional designs. The Fernic T-9 , a three-surface monoplane, flew in 1929. Fernic was killed in an accident while flying its successor

1225-625: Was poorly understood and typically pitch control was on the front surface with the rear surface also lifting, leading to instability in pitch. The Kress Drachenflieger of 1901 and Dufaux triplane of 1908 had insufficient power to take off. More successful types included the Voisin-Farman I (1907) and Curtiss No. 1 (1909). The Wright Brothers too experimented on the basic Flyer design in an effort to obtain both controllability and stability, flying it at various times in first canard, then three surface and finally conventional configurations. By

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