aerei curiosi

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Un altro che si accontenta di essere brutto: Gwinn Aircar

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Kamov-Skrzhinski KASKR-2

1930

 

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Jovair Sedan 4A 1963

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Yuriev

1912

 

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Spero non sia già stato postato, ma questo capolavoro è da Nobel.

 

 

Petroczy-Karman-Zurovec PKZ 2 1918

 

The Petroczy-Karman-Zurovec PKZ 2 helicopter, despite its name, was invented by Wilhelm Zurovec for which he alone received German patent No. 347,578, dated 12 February 1918. Unlike the PKZ 1, which was government funded, the PKZ 2 was privately financed by the Hungarian Bank and the firm of Dr. Liptak & Co AG, a large iron foundry and steel fabricator located near Budapest which established an experimental section under Zurovec's direction in late 1917.

 

The PKZ 2 has been amply described in post-war and contemporary literature, yet in virtually all accounts the design is incorrectly attributed to Karman who, in 1919 by claiming sole authorship and totally neglecting to mention the true inventor, Wilhelm Zurovec, deviously reaped the lion's share of the honors (documented by Zurovec correspondence in the Karman Archive). It is a great pity that Zurovec has never received the full measure of recognition that he surely deserves as one of the outstanding pioneers of helicopter development.

 

In the design of the PKZ 2 helicopter, Zurovec incorporated the concept of using counter-rotating rotors to cancel torque effects. Each rotor, with a diameter of 6 meters, represented an ingenious combination of old-world craftsmanship with modern applied engineering. Power was supplied by three 100hp Gnome rotary engines, that drove the rotors at 600 rpm through a common gearbox. The light, tubular airframe, easily disassembled for transport, rested on a patented central air-bag cushion (1 meter diameter) and three smaller cushions mounted on the outriggers. The cushions were kept inflated by an air pump attached to the rotor drive. Three tethering cables affixed to the outriggers ran through pulleys anchored in the ground and were controlled by separate, electric winches. The total weight of the PKZ 2 with fuel for one hour, but without observer and machine gun, was approximately 1200kg. Two forms of parachute rescue were planned. One was to carry the observer and aircraft safely to earth, and the other was a cannon-launched parachute that would clear the rotors and lift the observer to safety.

 

The PKZ 2 was test flown for the first time at the Liptak factory on 2 April 1918. After several flights, one lasting up to one hour, tests were suspended on 5 April because engine power was insufficient to permit safe hovering above 1.2m height. The Gnome engines were replaced by three 120hp Le Rhones. Flight testing continued from 17 to 21 May, during which flights between 10 and 50 meters altitude were recorded. During periods of calm weather and smooth engine operation, the excess lift measured at ground level was 150 to 200kg. As the PKZ 2 climbed, the loss of ground effect and the increase in tethering cable weight steadily reduced the excess lift. Yet, as long as excess lift sufficed to maintain proper cable tension, the PKZ 2 remained in stable hovering flight. At higher altitudes, the excess lift became marginal, causing the machine to slowly oscillate with increasing amplitude. Provided the tethering cables were retracted at about 1.5m/s, the oscillations to cease in about 15 to 20 seconds.

 

On 10 June 1918, Zurovec was called upon to demonstrate the PKZ 2 for high ranking military authorities. Although the rotary engines had recently been overhauled, their operation the day before was erratic, and Zurovec, fearing the worst, was reluctant to proceed. But what could a mere Leutnant do against the weight of official brass eager to see the wonder machine fly? Taking advantage of the zero wind conditions, the PKZ 2 with the observer's basket in place took-off at 5:40 and twice rose to 7-8 meters height, showing "considerable rocking motion." The basket was removed and the PKZ 2 took off again at 6:07 in a wind of 6-7 meters per second, climbing to a height of 12 meters. Due to overheating, the engine power dropped off and the helicopter began to pitch with increasing frequency until the tether-winch crew could no longer control the machine. The PKZ 2 crashed from two meters height, severely damaging the airframe and splintering the rotors. In a careful review of progress to date, Uzelac, realizing that the technical problems were too complex to resolve quickly, cancelled the project on 21 June 1918. Zurovec, Karman, and Liptak were directed to compile a record that would be a basis for further investigation when peace returned. Zurovec, refusing to accept defeat, devised a method to water-cool the rotary engines! He reported on 1 September that the PKZ 2 helicopter would be ready for further testing or 1 November 1918. By then it was too late.

 

 

 

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Hoppicopter Model 103

1947

 

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Bensen B-8MH "Hover-Gyro"

1976

 

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American Helicopter XA-8 / XH-26

1952

 

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Saro P.507

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Frantisek Novak No.1: The first helicopter made by Frantisek Novak before WWII started.

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Altro mio coetaneo!

 

 

PZL-Swidnik JK-1 "Trzmiel" 1957

 

Single-seat open frame ultra-light helicopter with two rotor-tip mounted Wojcicki pulse-jets. Prot. FF 28 June 1957. 2 built.

 

 

 

 

A new jet-powered helicopter, the JK-1 Trzmiel, designed by J. Kotlinski, a former member of Zurakowski's design team, was completed at the I.L. (Aircraft Institute) in the Spring of 1957 and was flight-tested later in the same year. TYPE: Light pulse-jet-powered helicopter. ROTOR SYSTEM: Two-bladed main rotor with small two-blade servo-rotor above main rotor and two-blade tail rotor. Main rotor blades, with a steel spar in the leading edge, are filled with plastic and have sheet duralumin skin. Servo-rotor of two circular planform blades mounted on short streamline stubs. Two-blade small diameter directional control rotor at the rear end of fuselage frame. Total main disc area 38m2. FUSELAGE: Uncovered steel-tube structure. POWER PLANT: Two 11-kg Wojcicki pulse-jets mounted at tips of main rotor blades.

 

 

 

 

 

Technical data for JK-1

 

Engine: 2 x Wojcicki turbojet, rated at 12.5kg, main rotor diameter: 7m, height: 2.35m, take-off weight: 340kg, max speed: 131km/h, endurance: 15min

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McCulloch MC-4

1951

 

 

 

This attractive little aeroplane was the first tandem-rotor helicopter to be certificated by the U.S. Civil Aeronautics Administration for commercial use, and is also one of the smallest helicopters to be built with a tandem layout. Its development began in 1946 with the Helicopter Engineering and Research Corporation headed by D.K. Jovanovich and F. Kozloski, where a small 2-seat prototype (N9000H) was built with the designation JOV-3. This aircraft, powered by a 125hp Lycoming O-290, was flown successfully in 1948. It had 3-blade rotors of 5.64m diameter, a gross weight of 618kg, a maximum speed of 161km/h and a range of 221km.

Jovanovich and Kozloski transferred in 1949 to the newly-formed helicopter division of the McCulloch Motors Corporation, where an enlarged development of the JOV-3 was built as the MC-4 with 6.71m rotors and a 165hp Franklin 6V4-165-832 engine. This prototype (N4070K) flew for the first time on so March 1951, and soon afterwards McCulloch began the construction of a prototype MC-4C (N4071K) and three generally similar YH-30's (52-5837 to '39) for evaluation by the U.S. Army. These were slightly larger than the MC-4, having 200hp Franklins and egg-shaped tail fins mounted on outriggers below the rear rotor head. The YH-30's trials programme yielded no military orders, and no civilian customers were immediately forthcoming for the MC-4C, which was certificated by the CAA on 17 February 1953. Jovanovich persevered with the design, however, and after forming his own Jovair Corporation some years later produced N4071K in developed form as the prototype for a new 4-seat private or executive helicopter known as the Sedan 4E. The Franklin 6A-335 of 210hp was now installed and the fuselage offered comfortable accommodation and easy 4-door access to 3 passengers in addition to the pilot. A supercharged version, the Sedan 4ES, was offered with a 225hp Franklin 6AS-335. The Sedan 4E received type approval from the FAA in March 1963, and some two years later small-scale production of this version was begun; the current version, with a 235hp 6A-350 engine, is slightly heavier. In mid-1963 Jovair offered the stripped-fuselage Sedan 4A as an agricultural, training or utility cargo version, with provision for some 450kg of cargo or crop spraying equipment in place of the rear passenger compartment. Aviastar

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HERC Jov-3

1948

 

 

Tandem rotor machine powered by a 100hp Franklin engine. It had a neat fuselage of steel tube covered with aluminium and fabric, with a tricycle undercarriage and a forward cockpit for two occupants seated in tandem. The rear pylon allowed the rear rotor to turn on a higher plane than the forward rotor so that the arcs could overlap safely.

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Ward helicopter 1876

 

Non spo come speravano che questo coso potesse volare...

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Ben Showers Aero "Skytwister"

 

Technical data: Engine: 1 x Rotax 582 rated at 48.6kW, main rotor diameter: 6.55m, length: 4.80m, height: 2.03m, take-off weight: 302kg, empty weight: 144kg, max speed: 137km/h, cruising speed: 105km/h

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Hiller "Sky Bus"

project

 

 

 

 

Hiller Helicopter's conception of a future forty-to-fifty passenger ram jet transport.

Modificato 5 Gennaio 2009 da Blue Sky

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Sznycer Omega BS-12 1956

 

The SG-VI-D did not go into production and Sznycer started a new company, Allied Aero Industries, in the USA to develop and build the Omega BS-12 utility helicopter. This had a flying crane layout, with a forward four-seat crew pod and an open tubular rear fuselage and fixed tricycle undercarriage. A metal cargo box could be suspended beneath the fuselage mid-section. The BS-12 (N267B) used two 210hp Franklin engines positioned end-to-end above the rear fuselage. The prototype flew on 29 October 1956, and was followed by a revised version - the BS-12B (N290B). The Omega design was progressively upgraded with detail design changes, notably to the cabin pod and to the engines. The BS-12D-1 (N285B) had two 260hp Lycoming O-540 engines and a five-seat cabin. The second BS-12D-1 (N286B) was fitted with supercharged Franklin 6AS-335 engines and redesignated BS-12D-3. In 1960, the investors backing the Omega designs withdrew support and further development was terminated.

 

 

 

 

Technical data for Omega SB-12

 

Rotor diameter: 11.89m, fuselage length: 11.12m, height: 3.96m, weight empty: 1338kg, gross weight: 1905kg, max speed: 138km/h, service ceiling: 3450m, range: 250km

 

 

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Gyrodyne GCA-2C

1952

 

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Westland WG.25 "Mote"

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Filper Beta 400

1967

 

 

Under the direction of William Orr, Filper Research designed a novel helicopter using the 'Gyroflex Rotor', which employed special balance weights fitted to the roots of the rotor blades instead of conventional flapping or lead-lag hinges, or other hub stability devices. This concept was tested on the Filper Helicopter (N9712C) which had fore and aft rotor pylons and the pilot sitting astride a central beam which also carried the engine. The commercial development, however, was the Filper Beta 100A. This was a tandem rotor machine with a two-seat cabin and pylon at the rear, and the engine with the forward pylon in front. This curious arranagment resulted in the pilot being unusually far from the front of the helicopter. The Beta 200 prototype (N5000F) was first flown on 26 May 1966. Filper planned several versions of the Beta with either two seats (Model 200A and 300) or four seats (Model 400A and 600A). The four-seat models had a fuselage which was stretched by 36-inches and the first Beta 400A (N5003F) was flown on 13 July 1967. The Beta models had various powerplants - namely the 210hp Continental IO-360-E (Model 200A), Allison 250-C18 turbine (Model 300) and 250hp Continental IO-520 (400A). Details of the Model 600A are unknown. Registration records show that 32 Betas were completed, comprising two Model 100As, 29 Model 400As and one Model 600A, but there is some doubt as to whether all of these were completed. It is believed the company ceased operations in 1969. Aviastar!

Modificato 5 Gennaio 2009 da Blue Sky

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Ultralight Aviation Sky Dart SD2

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Groen Gyrolifter

project

 

 

TYPE: Convertiplane

 

PROGRAMME: Response to request of US Defense Advanced Research Projects Agency (DARPA) for proposals to meet requirement for Advanced Maneuver Transport (AMT) with VTOL and heavy lift capability. Proposal is based upon the integration of a large-diameter rotor powered by tipjets with an existing fixed-wing turboprop freighter.

Groen is proposing to DARPA that it be designated to undertake the necessary research and development to produce an intermediate scale technology demonstrator leading to full-scale prototype based on the Lockheed C-130 aircraft.

DESIGN FEATURES: Heavy lift gyrodyne with tipjets for rotor drive; large fuselage with passenger accommodation and rear freight doors; VTOL capability; four turboprop engines; stub-wings to share flight load, to reduce rotor speed and increase aircraft airspeed; and mostly composites construction with metal engine attachments. Complete cargo handling system. Tipjets provide a highly efficient power/weight ratio to enable vertical take-off and landing with a 18,144kg payload, but are shut down in other flight modes, permitting the aircraft to achieve a range of up to 1,850km using the efficiencies of turboprop operation in cruise. Rotor system incorporates five mission-adaptive blades incorporating Westland BERP (British Experimental Rotor Programme) paddle blade tips, which optimise rotor performance during all flight regimes, thereby increasing airspeeds above that of any contemporary helicopter, while reducing fuel consumption.

FLYING CONTROLS: Fly-by-wire, fully integrated flight, engine tipjet and rotor management system.

STRUCTURE: Mainly composites structure for fuselage and wings, and metal inserts for landing gear and engine mounting points. Composites rotor blades and unique rotor head design.

LANDING GEAR: Tricycle retractable landing gear with steerable dual-wheel nose landing gear and bogie-type main gear.

POWER PLANT: One Rolls-Royce AD2100 or Rolls-Royce AE 1107Ñ upgraded from 4,586kW to about 6,711kW. Fuel capacity 11,340kg.

ACCOMODATION: Pilot and navigator; or two pilots plus loadmaster.

SYSTEMS: Electrical and hydraulic systems, including APU.

AVIONICS: Fully integrated battlefield systems. Aviastar

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Spero non sia già stato postato.

 

 

TsAGIA-7

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SBIZ M-1

1950

 

 

An experimental tip-jet helicopter designed by engineers of the Bratukhin design bureau. Only few tethered flights were made before the project was abandoned in 1951.

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Spero non l'abbiano già postato, perché stamattina ho la febbre e non ho voglia di ripassare tutto.

 

 

Breguet-Richet Gyroplane No.2 1908

 

Helicopter-aeroplane, combining the principles of the lifting screw with the aeroplane pure and simple. The screws are two in number, and are placed at an angle of 40° to the vertical between the front and rear biplanes.

 

They are driven by bevel gearing from a 50hp 8-cylinder Antoinette engine placed transversely, and are stated to give a starting lift of 300kg with a horizontal pull of 250kg at 300 r.p.m. Each screw has four flexible blades, and is 4.3m in diameter. Of the two main planes, the biplane at the rear has a spread of 14m, while the monoplane in front is 10m across; together (and with a few other smaller planes) a total of 60 sq. metres surface is provided. The rudder is behind, and the elevator in front beneath the fixed monoplane.

 

Between the main plane are two horizontal steering planes, which twist in an inverse sense, and are controlled by a pedal. The machine weighs 550kg, and has been constructed at Douai by M. Breguet; its frame is made entirely of steel. It is very large and looks cumbersome, but is not very heavy for its dimensions.

 

 

In 1908 the Breguet-Richet collaboration produced a No.2 Gyroplane, powered by a 55hp Renault engine and having two forward-tilting 2-blade rotors with a diameter of 7.85m and, in addition, fixed wings giving an extra 50m2 of lifting surface. This machine made a number of successful flights in the summer of 1908, but was severely damaged in a 'heavy' landing on 19 September. In rebuilt form as the No.2bis it was displayed statically at Paris in December 1908 and made one test flight in the following April, but a month later the Breguet premises were wrecked by a hurricane. This, and the shortage of contemporary engines with an adequate power/weight ratio, caused Breguet to abandon rotary-winged development until the appearance of the Breguet-Dorand design in the 1930s.

 

 

 

P.S.: si tratta dei primi tentativi, è vero, quindi vanno guardati con un po' di comprensione. Ma... avete notato la quantità di accrocchi made in Frogland?