The Yakovlev Yak-1 ( Russian : Яковлев Як-1 ) was a Soviet fighter aircraft of World War II . The Yak-1 was a single-seat monoplane with a composite structure and wooden wings; production began in early 1940.
76-583: The Yak-1 was a maneuverable, fast and competitive fighter aircraft. The composite-wooden structure made it easy to maintain and the engine proved to be reliable. It formed the basis for subsequent developments from the Yakovlev bureau and was the founder of a family of aircraft, with some 43,000 being built. As a reward, designer Alexander Yakovlev was awarded the Order of Lenin ( Russian : Орден Ленина, Orden Lenina ) (the highest civilian decoration bestowed by
152-625: A Yak (with M-105PF engine) and a Bf 109F revealed that the Messerschmitt had only marginally superior maneuverability at 1,000 m (3,300 ft), though the German fighter could gain substantial advantage over the Yak-1 within four or five nose-to-tail turns. At 3,000 m (9,800 ft), the capabilities of the two fighters were nearly equal, as combat was essentially reduced to head-on attacks. At altitudes over 5,000 m (16,000 ft),
228-464: A bent aluminium sheet for blades, thus creating an airfoil shape. They were heavily undercambered , and this plus the absence of lengthwise twist made them less efficient than the Wright propellers. Even so, this was perhaps the first use of aluminium in the construction of an airscrew. Originally, a rotating airfoil behind the aircraft, which pushes it, was called a propeller, while one which pulled from
304-473: A childhood fascination with the Chinese flying top, developed a model of feathers, similar to that of Launoy and Bienvenu, but powered by rubber bands. By the end of the century, he had progressed to using sheets of tin for rotor blades and springs for power. His writings on his experiments and models would become influential on future aviation pioneers. William Bland sent designs for his "Atmotic Airship" to
380-461: A craft that weighed 3.5 long tons (3.6 t), with a 110 ft (34 m) wingspan that was powered by two 360 hp (270 kW) steam engines driving two propellers. In 1894, his machine was tested with overhead rails to prevent it from rising. The test showed that it had enough lift to take off. One of Pénaud's toys, given as a gift by their father , inspired the Wright brothers to pursue
456-530: A day (four Bf 109s and a Ju 87, on 6 August 1942). The Yak-1 was also the first type operated by the 1 Pułk Lotnictwa Myśliwskiego "Warszawa" (1st Polish Fighter Regiment "Warsaw"). Soviet naming conventions obscure the fact that the Yak-1 and its successors – the Yak-7, Yak-9 and Yak-3 – are essentially the same design, comparable to the numerous Spitfire or Bf 109 variants. Were the Yaks considered as one type,
532-416: A fixed-pitch prop once airborne. The spring-loaded "two-speed" VP prop is set to fine for takeoff, and then triggered to coarse once in cruise, the propeller remaining coarse for the remainder of the flight. After World War I , automatic propellers were developed to maintain an optimum angle of attack. This was done by balancing the centripetal twisting moment on the blades and a set of counterweights against
608-467: A large number of blades. A fan therefore produces a lot of thrust for a given diameter but the closeness of the blades means that each strongly affects the flow around the others. If the flow is supersonic, this interference can be beneficial if the flow can be compressed through a series of shock waves rather than one. By placing the fan within a shaped duct , specific flow patterns can be created depending on flight speed and engine performance. As air enters
684-528: A low- drag wing and as such are poor in operation when at other than their optimum angle of attack . Therefore, most propellers use a variable pitch mechanism to alter the blades' pitch angle as engine speed and aircraft velocity are changed. A further consideration is the number and the shape of the blades used. Increasing the aspect ratio of the blades reduces drag but the amount of thrust produced depends on blade area, so using high-aspect blades can result in an excessive propeller diameter. A further balance
760-415: A propeller efficiency of about 73.5% at cruise for a Cessna 172 . This is derived from his "Bootstrap approach" for analyzing the performance of light general aviation aircraft using fixed pitch or constant speed propellers. The efficiency of the propeller is influenced by the angle of attack (α). This is defined as α = Φ - θ, where θ is the helix angle (the angle between the resultant relative velocity and
836-453: A propeller suffers when transonic flow first appears on the tips of the blades. As the relative air speed at any section of a propeller is a vector sum of the aircraft speed and the tangential speed due to rotation, the flow over the blade tip will reach transonic speed well before the aircraft does. When the airflow over the tip of the blade reaches its critical speed , drag and torque resistance increase rapidly and shock waves form creating
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#1732775722881912-680: A school project. In 1924, he built a glider, the AVF-10, which made its first flight on 24 September 1924. The design won an award and secured him a position as a worker at the Zhukovsky Air Force Military Engineering Academy . However, his repeated attempts to gain admission to the Academy were denied due to his “lack of proletariat origins”. In 1927, Yakovlev designed the AIR-1 ultralight aircraft. This
988-454: A sharp increase in noise. Aircraft with conventional propellers, therefore, do not usually fly faster than Mach 0.6. There have been propeller aircraft which attained up to the Mach 0.8 range, but the low propeller efficiency at this speed makes such applications rare. The tip of a propeller blade travels faster than the hub. Therefore, it is necessary for the blade to be twisted so as to decrease
1064-473: A significant advantage over its Soviet competitors. A full circle turn took just 17 seconds in the Yak-1M. The MiG-3, which had the best high-altitude performance, did poorly at low and medium altitudes and its light armament made it unsuitable for ground attack. The LaGG-3 experienced a significant degradation in performance (as much as 100 km/h (62 mph) on some aircraft) compared to its prototypes due to
1140-583: A small coaxial modeled after the Chinese top but powered by a wound-up spring device and demonstrated it to the Russian Academy of Sciences . It was powered by a spring, and was suggested as a method to lift meteorological instruments. In 1783, Christian de Launoy , and his mechanic , Bienvenu, used a coaxial version of the Chinese top in a model consisting of contrarotating turkey flight feathers as rotor blades, and in 1784, demonstrated it to
1216-417: A spring and the aerodynamic forces on the blade. Automatic props had the advantage of being simple, lightweight, and requiring no external control, but a particular propeller's performance was difficult to match with that of the aircraft's power plant. The most common variable pitch propeller is the constant-speed propeller . This is controlled by a hydraulic constant speed unit (CSU). It automatically adjusts
1292-697: A top speed of 620 km/h (390 mph) at 6,000 m (20,000 ft), combat range of 600 km (370 mi), a climb to 10,000 m (33,000 ft)) of under 11 minutes, armed with 2 × 7.62 mm (0.300 in) ShKAS machine guns and 1 × 12.7 mm (0.50 in) Berezin BS heavy machine gun. I-26-2 had a turbocharged M-106 engine with a top speed of 650 km/h (400 mph) at 10,000 m (33,000 ft) and armament of 2 × 7.62 mm (0.300 in) ShKAS machine guns. The design took full advantage of Yakovlev OKB's experience with sports aircraft and promised agility as well as high top speed. Since
1368-455: Is hydraulic, with engine oil serving as the hydraulic fluid. However, electrically controlled propellers were developed during World War II and saw extensive use on military aircraft, and have recently seen a revival in use on home-built aircraft. Another design is the V-Prop , which is self-powering and self-governing. On most variable-pitch propellers, the blades can be rotated parallel to
1444-479: Is suitable for airliners, but the noise generated is tremendous (see the Antonov An-70 and Tupolev Tu-95 for examples of such a design). Forces acting on the blades of an aircraft propeller include the following. Some of these forces can be arranged to counteract each other, reducing the overall mechanical stresses imposed. The purpose of varying pitch angle is to maintain an optimal angle of attack for
1520-409: Is that using a smaller number of blades reduces interference effects between the blades, but to have sufficient blade area to transmit the available power within a set diameter means a compromise is needed. Increasing the number of blades also decreases the amount of work each blade is required to perform, limiting the local Mach number – a significant performance limit on propellers. The performance of
1596-489: Is used to help slow the aircraft after landing and is particularly advantageous when landing on a wet runway as wheel braking suffers reduced effectiveness. In some cases reverse pitch allows the aircraft to taxi in reverse – this is particularly useful for getting floatplanes out of confined docks. Counter-rotating propellers are sometimes used on twin-engine and multi-engine aircraft with wing-mounted engines. These propellers turn in opposite directions from their counterpart on
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#17327757228811672-545: The French Academy of Sciences . A dirigible airship was described by Jean Baptiste Marie Meusnier presented in 1783. The drawings depict a 260-foot-long (79 m) streamlined envelope with internal ballonets that could be used for regulating lift. The airship was designed to be driven by three propellers. In 1784 Jean-Pierre Blanchard fitted a hand-powered propeller to a balloon, the first recorded means of propulsion carried aloft. Sir George Cayley , influenced by
1748-578: The McDonnell XF-88B experimental propeller-equipped aircraft. Supersonic tip-speeds are used in some aircraft like the Tupolev Tu-95 , which can reach 575 mph (925 km/h). The earliest references for vertical flight came from China. Since around 400 BC, Chinese children have played with bamboo flying toys . This bamboo-copter is spun by rolling a stick attached to a rotor between one's hands. The spinning creates lift, and
1824-731: The Soviet Air Force during World War II . Particularly well known are the Yak-1 , Yak-3 , Yak-7 and Yak-9 as well as the Yak-6 transport. In 1945 Yakovlev designed one of the first Soviet aircraft with a jet engine, the Yak-15 . He also designed the first Soviet all-weather interceptor, the Yak-25P , and the first Soviet supersonic bomber, the Yak-28 . In the post-war period, Yakovlev
1900-571: The Soviet Union ), a 100,000 ruble prize, and a ZIS motor car. Before the war, Yakovlev was best known for building light sports aircraft. His Yak-4 light bomber impressed the Soviet government enough to order the OKB to design a new fighter with a Klimov M-106 V-12 liquid-cooled engine . Formal specifications, which were released on 29 July 1939, called for two prototypes – I-26-1 with
1976-403: The Tupolev Tu-95 propel it at a speed exceeding the maximum once considered possible for a propeller-driven aircraft using an exceptionally coarse pitch. Early pitch control settings were pilot operated, either with a small number of preset positions or continuously variable. The simplest mechanism is the ground-adjustable propeller , which may be adjusted on the ground, but is effectively
2052-1088: The 37,000 built would constitute the most produced fighter in history. That total would also make the Yak one of the most prolific aircraft in history, roughly equal to the best known Soviet ground attack type of World War II, the IL-2 Shturmovik . Losses were the highest of all fighter types in service in the USSR: from 1941 to 1945, VVS KA lost 3,336 Yak-1s: 325 in 1941, 1,301 the following year, 1,056 in 1943, 575 in 1944 and 79 in 1945. Data from Dimensions from OKB Yakovlev , weights and performance from Yakovlev Aircraft since 1924 General characteristics Performance Armament Related development Aircraft of comparable role, configuration, and era Related lists Alexander Sergeevich Yakovlev Alexander Sergeyevich Yakovlev ( Russian : Алекса́ндр Серге́евич Я́ковлев ; 1 April [ O.S. 19 March] 1906 – 22 August 1989)
2128-535: The Great Exhibition held in London in 1851, where a model was displayed. This was an elongated balloon with a steam engine driving twin propellers suspended underneath. Alphonse Pénaud developed coaxial rotor model helicopter toys in 1870, also powered by rubber bands. In 1872 Dupuy de Lome launched a large navigable balloon, which was driven by a large propeller turned by eight men. Hiram Maxim built
2204-589: The M-106 was delayed, the design was changed to incorporate the Klimov M-105 P V-12 engine, with a 20 mm (0.787 in) ShVAK cannon in the "vee" of the engine block, in a motornaya pushka mount. I-26-I first flew on 13 January 1940 and suffered from oil overheating which was never completely resolved, resulting in 15 emergency landings during early testing. On 27 April 1940, I-26-1 crashed, killing its test pilot Yu.I. Piontkovskiy . The investigation of
2280-566: The Soviet Union on 22 June 1941, development of promising designs, like the Polikarpov I-185 , proved unfeasible. Yakovlev might have been Joseph Stalin 's favorite, which may have been in the Yak-1's favor. Simultaneous manufacturing and testing of a design that required as many improvements as I-26 caused much disruption of production. Almost 8,000 changes were made to the blueprints by 1941, with an additional 7,000 implemented
2356-642: The USSR (1946–1989). Yakovlev retired 21 August 1984. He was buried in the Novodevichy Cemetery in Moscow. Propeller (aircraft) In aeronautics , an aircraft propeller , also called an airscrew , converts rotary motion from an engine or other power source into a swirling slipstream which pushes the propeller forwards or backwards. It comprises a rotating power-driven hub, to which are attached several radial airfoil -section blades such that
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2432-655: The Yak was more manoeuvrable. The engine's nominal speed at low altitudes was lowered to 2,550 rpm, and the superiority of the Bf 109F at these altitudes was reduced. The Yak-1's armament would be considered too light by Western standards but was typical of Soviet aircraft, pilots preferring a few guns grouped on the centerline to improve accuracy and reduce weight. Wing guns were rarely used on Soviet fighters and when they were supplied, they were often removed (as they were from US-supplied Bell P-39 Airacobras ). Avoiding wing guns reduced weight and demonstrably improved roll rates (the same
2508-399: The air in the propeller slipstream. Contra-rotation also increases the ability of a propeller to absorb power from a given engine, without increasing propeller diameter. However the added cost, complexity, weight and noise of the system rarely make it worthwhile and it is only used on high-performance types where ultimate performance is more important than efficiency. A fan is a propeller with
2584-428: The aircraft maintain speed and altitude with the operative engines. Feathering also prevents windmilling , the turning of engine components by the propeller rotation forced by the slipstream; windmilling can damage the engine, start a fire, or cause structural damage to the aircraft. Most feathering systems for reciprocating engines sense a drop in oil pressure and move the blades toward the feather position, and require
2660-405: The airflow to stop rotation of the propeller and reduce drag when the engine fails or is deliberately shut down. This is called feathering , a term borrowed from rowing . On single-engined aircraft, whether a powered glider or turbine-powered aircraft, the effect is to increase the gliding distance. On a multi-engine aircraft, feathering the propeller on an inoperative engine reduces drag, and helps
2736-410: The angle of attack of the blade gradually and therefore produce uniform lift from the hub to the tip. The greatest angle of incidence, or the highest pitch, is at the hub while the smallest angle of incidence or smallest pitch is at the tip. A propeller blade designed with the same angle of incidence throughout its entire length would be inefficient because as airspeed increases in flight, the portion near
2812-407: The blade pitch in order to maintain a constant engine speed for any given power control setting. Constant-speed propellers allow the pilot to set a rotational speed according to the need for maximum engine power or maximum efficiency, and a propeller governor acts as a closed-loop controller to vary propeller pitch angle as required to maintain the selected engine speed. In most aircraft this system
2888-440: The blade rotation direction) and Φ is the blade pitch angle. Very small pitch and helix angles give a good performance against resistance but provide little thrust, while larger angles have the opposite effect. The best helix angle is when the blade is acting as a wing producing much more lift than drag. However, 'lift-and-drag' is only one way to express the aerodynamic force on the blades. To explain aircraft and engine performance
2964-403: The blade tips approach the speed of sound. The maximum relative velocity is kept as low as possible by careful control of pitch to allow the blades to have large helix angles. A large number of blades are used to reduce work per blade and so circulation strength. Contra-rotating propellers are used. The propellers designed are more efficient than turbo-fans and their cruising speed (Mach 0.7–0.85)
3040-402: The crash found that the pilot had performed two consecutive barrel rolls at low altitude, which was in violation of the test flight plan. It was believed that during the first roll, the main landing gear became unlocked, causing it to crash through the wing during the second roll. It has been speculated that Piontkovskiy's deviation from the flight plan was caused by frustration that his aircraft
3116-467: The dream of flight. The twisted airfoil (aerofoil) shape of an aircraft propeller was pioneered by the Wright brothers. While some earlier engineers had attempted to model air propellers on marine propellers , the Wright Brothers realized that a propeller is essentially the same as a wing , and were able to use data from their earlier wind tunnel experiments on wings, introducing a twist along
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3192-575: The duct, its speed is reduced while its pressure and temperature increase. If the aircraft is at a high subsonic speed this creates two advantages: the air enters the fan at a lower Mach speed; and the higher temperature increases the local speed of sound. While there is a loss in efficiency as the fan is drawing on a smaller area of the free stream and so using less air, this is balanced by the ducted fan retaining efficiency at higher speeds where conventional propeller efficiency would be poor. A ducted fan or propeller also has certain benefits at lower speeds but
3268-431: The feathering process or the feathering process may be automatic. Accidental feathering is dangerous and can result in an aerodynamic stall ; as seen for example with Yeti Airlines Flight 691 which crashed during approach due to accidental feathering. The propellers on some aircraft can operate with a negative blade pitch angle, and thus reverse the thrust from the propeller. This is known as Beta Pitch. Reverse thrust
3344-430: The following year and 5,000 more in 1942. Production was further slowed by shortages of engines, propellers , radiators , wheels and cannons. Shortages of quality materials resulted in plywood being shed from the wings of several aircraft. Factory No.292, the main manufacturer of Yak-1s was bombed on 23 June 1941 and burned to the ground; production resumed amid the ruins on 29 June. Due to loose tolerances, each aircraft
3420-463: The front was a tractor . Later the term 'pusher' became adopted for the rear-mounted device in contrast to the tractor configuration and both became referred to as 'propellers' or 'airscrews'. The understanding of low speed propeller aerodynamics was fairly complete by the 1920s, but later requirements to handle more power in a smaller diameter have made the problem more complex. Propeller research for National Advisory Committee for Aeronautics (NACA)
3496-574: The fuselage – clockwise on the left engine and counterclockwise on the right – however, there are exceptions (especially during World War II ) such as the P-38 Lightning which turned "outwards" (counterclockwise on the left engine and clockwise on the right) away from the fuselage from the WW II years, and the Airbus A400 whose inboard and outboard engines turn in opposite directions even on
3572-414: The hub would have a negative AOA while the blade tip would be stalled. There have been efforts to develop propellers and propfans for aircraft at high subsonic speeds. The 'fix' is similar to that of transonic wing design. Thin blade sections are used and the blades are swept back in a scimitar shape ( scimitar propeller ) in a manner similar to wing sweepback, so as to delay the onset of shockwaves as
3648-400: The length of the blades. This was necessary to maintain a more uniform angle of attack of the blade along its length. Their original propeller blades had an efficiency of about 82%, compared to 90% for a modern (2010) small general aviation propeller, the 3-blade McCauley used on a Beechcraft Bonanza aircraft. Roper quotes 90% for a propeller for a human-powered aircraft. Mahogany was
3724-440: The manufacturer's inexperience with its special wooden construction, which suffered from warping and rotting when exposed to the elements. The Yak-1's plywood covering also suffered from the weather, but the steel frame kept the aircraft largely intact. Early aircraft suffered from fuel leaks, spot-welded fuel tanks failing from vibration. The canopy could not be opened under certain conditions in earlier models and some pilots had
3800-432: The other wing to balance out the torque and p-factor effects. They are sometimes referred to as "handed" propellers since there are left hand and right hand versions of each prop. Generally, the propellers on both engines of most conventional twin-engined aircraft spin clockwise (as viewed from the rear of the aircraft). To eliminate the critical engine problem, counter-rotating propellers usually turn "inwards" towards
3876-417: The pilot to pull the propeller control back to disengage the high-pitch stop pins before the engine reaches idle RPM . Turboprop control systems usually use a negative torque sensor in the reduction gearbox, which moves the blades toward feather when the engine is no longer providing power to the propeller. Depending on design, the pilot may have to push a button to override the high-pitch stops and complete
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#17327757228813952-561: The propeller blades, giving maximum efficiency throughout the flight regime. This reduces fuel usage. Only by maximising propeller efficiency at high speeds can the highest possible speed be achieved. Effective angle of attack decreases as airspeed increases, so a coarser pitch is required at high airspeeds. The requirement for pitch variation is shown by the propeller performance during the Schneider Trophy competition in 1931. The Fairey Aviation Company fixed-pitch propeller used
4028-575: The rear fuselage. The Yak-1 was well liked by its pilots; Nikolai G. Golodnikov considered that the Yak-1B, flown by experienced pilots, could meet the Bf 109F-4 and G-2 on equal terms. The French Normandie-Niemen squadron selected the primitive model Yak-1M (that had a cut-down fuselage to allow all-round vision) when it was formed, in March 1943. Twenty-four of these aircraft were sent to the all-female 586th Fighter Aviation Regiment , whose pilots included
4104-410: The reduction shaft. The Yak-1 was better than the Bf 109E but inferior to the Bf 109F – its main opponent – in rate of climb at all altitudes, although it could complete a circle at the same speed (20–21 seconds at 1,000 m (3,300 ft)). The Bf 109, with its automatic wing slats, had a lower stall speed and was more stable in sharp turns and vertical aerobatic figures. A simulated combat between
4180-411: The same force is expressed slightly differently in terms of thrust and torque since the required output of the propeller is thrust. Thrust and torque are the basis of the definition for the efficiency of the propeller as shown below. The advance ratio of a propeller is similar to the angle of attack of a wing. A propeller's efficiency is determined by Propellers are similar in aerofoil section to
4256-410: The same wing. A contra-rotating propeller or contra-prop places two counter-rotating propellers on concentric drive shafts so that one sits immediately 'downstream' of the other propeller. This provides the benefits of counter-rotating propellers for a single powerplant. The forward propeller provides the majority of the thrust, while the rear propeller also recovers energy lost in the swirling motion of
4332-467: The single ShVAK cannon. Nevertheless, these lighter aircraft were popular with experienced pilots, for whom the reduction in armament was acceptable and combat experience in November 1942 showed a much improved kill-to-loss ratio. In the autumn of 1942, the Yak-1B appeared, with the more powerful M-105P engine and a single 12.7 mm UBS machine gun instead of the two ShKAS. Although this did not increase
4408-421: The sliding portion of the canopy removed. The first 1,000 Yak-1s had no radios; wireless equipment became common by spring 1942 and obligatory by August 1942 but Soviet radios were notoriously unreliable and short-ranged, so they were frequently removed to save weight. The M-105 could not tolerate negative G forces which starved it of fuel and suffered from breakdowns of magnetos, speed governors and emitted oil from
4484-557: The time between the prototype and the beginning of production of service aircraft; the I-200 and I-301 were also ordered into production. The Yak-1 was slower than the I-200 and less heavily armed than the I-301, it enjoyed the advantage of having been started earlier, which gave it a consistent lead in testing and development over its competitors. Due to Operation Barbarossa the Axis invasion of
4560-503: The time of Operation Barbarossa on 22 June 1941, 425 Yak-1s had been built, although many were en route or still incomplete. 92 machines were fully operational in the Western Military Districts but most were lost in the first days. The Yak-1 was built as an escort fighter for Il-2 tactical bombers and combats took place below 4,000 m (13,000 ft), where the Yak-1 performed the best. The Yak-1 proved to have
4636-540: The total weight of fire much, the UBS machine-gun was much more effective than the two 7.62 mm ShKAS. The simple VV ring sight replaced the PBP gun-sight because of the very poor quality of the latter's lenses. The Yak-1 had a light tail, and it was easy to tip over and to hit the ground with the propeller. Often, technicians had to keep the tail down, which could lead to accidents, with aircraft taking off with technicians still on
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#17327757228814712-530: The toy flies when released. The 4th-century AD Daoist book Baopuzi by Ge Hong (抱朴子 "Master who Embraces Simplicity") reportedly describes some of the ideas inherent to rotary wing aircraft. Designs similar to the Chinese helicopter toy appeared in Renaissance paintings and other works. It was not until the early 1480s, when Leonardo da Vinci created a design for a machine that could be described as an "aerial screw" , that any recorded advancement
4788-599: The war, he helped supervise the evacuation of aircraft factories to the east, and the production organisation, while continuing as head designer of his Bureau. He was also a correspondent member of the USSR Academy of Science in 1943. In 1946 he was awarded the title " General-Colonel of Aviation". In 1976 Yakovlev became academician of the USSR Academy of Science. He was a deputy of the Supreme Soviet of
4864-512: The whole assembly rotates about a longitudinal axis. The blade pitch may be fixed, manually variable to a few set positions, or of the automatically variable "constant-speed" type. The propeller attaches to the power source's driveshaft either directly or through reduction gearing . Propellers can be made from wood, metal or composite materials . Propellers are most suitable for use at subsonic airspeeds generally below about 480 mph (770 km/h), although supersonic speeds were achieved in
4940-445: The wood preferred for propellers through World War I , but wartime shortages encouraged use of walnut , oak , cherry and ash . Alberto Santos Dumont was another early pioneer, having designed propellers before the Wright Brothers for his airships . He applied the knowledge he gained from experiences with airships to make a propeller with a steel shaft and aluminium blades for his 14 bis biplane in 1906. Some of his designs used
5016-434: The world's only female aces : Katya Budanova , with 5, and Lydia Litvyak (claims range between 5 and 12, plus two shared). Litvyak flew Yak-1 "Yellow 44", with an aerial mast, at first in 296th Fighter Aviation Regiment and then with 73rd Guards Fighter Aviation Regiment, until her death in combat on 1 August 1943. Another ace who flew the Yak-1 was Mikhail Baranov , who scored all his 24 victories with it, including five in
5092-739: Was a Soviet aeronautical engineer . He designed the Yakovlev military aircraft and founded the Yakovlev Design Bureau . Yakovlev joined the Communist Party of the Soviet Union in 1938. Yakovlev was born in Moscow , where his father was an employee of the Nobel Brothers oil company. From 1919 to 1921, he worked as a part-time courier while still in school, and in 1922 he built his first model aeroplane as part of
5168-677: Was being used for engine testing while I-26-2, built with the lessons of I-26-1 in mind, was already performing aerobatics . Technical problems with sub-assemblies provided by different suppliers raised the I-26-2's weight 400 kg (880 lb) above projected figures, which restricted the airframe to only 4.4 G, while oil overheating continued to occur. The many defects caused I-26-2 to fail government testing in 1940. Fortunately for Yakovlev, its competitors, I-200 (future Mikoyan-Gurevich MiG-3 ) and I-301 (future LaGG-3 ), also failed testing. Requested improvements were incorporated into I-26-3, which
5244-454: Was best known for the civilian airliner, the Yak-42 , a three-engine medium-range aircraft, and numerous aerobatic models. Yakovlev served under Joseph Stalin as a Vice-Minister of Aviation Industry between 1940 and 1946. Before the start of World War II, he made a number of trips abroad, including Italy, England and Germany, to study aircraft development in those countries. After the start of
5320-409: Was delivered for testing on 13 October 1940. Although it passed on 9 December 1940, the aircraft was still very much unfinished, its engine problems still unresolved. Troublesome and slow testing and development concerned Soviet officials, since I-26 was ordered into production under the name "Yak-1" on 19 February 1940, a mere month after I-26-1 made its maiden flight. The gamble was intended to reduce
5396-616: Was directed by William F. Durand from 1916. Parameters measured included propeller efficiency, thrust developed, and power absorbed. While a propeller may be tested in a wind tunnel , its performance in free-flight might differ. At the Langley Memorial Aeronautical Laboratory , E. P. Leslie used Vought VE-7s with Wright E-4 engines for data on free-flight, while Durand used reduced size, with similar shape, for wind tunnel data. Their results were published in 1926 as NACA report #220. Lowry quotes
5472-506: Was made towards vertical flight. His notes suggested that he built small flying models, but there were no indications for any provision to stop the rotor from making the craft rotate. As scientific knowledge increased and became more accepted, man continued to pursue the idea of vertical flight. Many of these later models and machines would more closely resemble the ancient bamboo flying top with spinning wings, rather than Leonardo's screw. In July 1754, Russian Mikhail Lomonosov had developed
5548-447: Was partially stalled on take-off and up to 160 mph (260 km/h) on its way up to a top speed of 407.5 mph (655.8 km/h). The very wide speed range was achieved because some of the usual requirements for aircraft performance did not apply. There was no compromise on top-speed efficiency, the take-off distance was not restricted to available runway length and there was no climb requirement. The variable pitch blades used on
5624-624: Was the first of ten aircraft he designed between 1927 and 1933. In 1927, Yakovlev finally gained admittance to the Academy and graduated in 1931. He was then assigned to the Moscow Aviation Plant No. 39, where his first design bureau of lightweight aviation was established in 1932. He became the main designer in 1935, then the chief designer (1956–1984) of aircraft for the Yakovlev Design Bureau. The Yakovlev Design Bureau developed many fighter aircraft used by
5700-497: Was true of the Bf 109F). The US and Britain considered heavy armament and high performance necessary, even at the cost of inferior maneuverability, while the Soviets relied on the marksmanship of their pilots coupled with agile aircraft. Even with the Yak-1's light armament, to reduce weight, modifications were made on the front line and on about thirty production aircraft: the 7.62 mm ShKAS machine-guns were removed, retaining only
5776-468: Was unique, with workers performing the final assembly having to mate dissimilar components. The left and right main landing gear could be of different lengths and different angles relative to the aircraft, which required adjusting their attachments to ensure an even stance for the aircraft and parts were often not interchangeable. Production of the Yak-1 ended in July 1944, with somewhere around 8,700 built. At
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