U-2 or Po-2 - multipurpose biplane, created under the direction of H. n. Polikarpov in 1927 year. One of the most popular aircraft in the world.
U-2 (In 2) – video
FROM 1919 , the main training aircraft in the USSR was the U-1, based at the British intelligence Avro-504, whose first flight took place as early as 1913 year. TO 1922 , the question arose about the need for more modern training machines, especially, by that time, the method of training the flight case has undergone significant changes. It was deemed necessary to carry out training on airplanes fly solo initial training, and grind skills on training (transition) machines.
Nikolai Polikarpov directly engaged in the development of training aircraft in 1923 g. One of his first works in this direction was the project of small two-seater training aircraft with ABC engine capacity 18 l. from. The machine was a cantilever monoplane pure forms with the maximum flight speed up to 107 kmh. However, the engine low power does not allow for training aerobatics. The project was not implemented.
In October 1924 Air Force, the NTC has made common tactical and technical requirements to aircrafts of initial training and transition. Stressed desire to have as such biplane with small landing speed.
Under these requirements in Polikarpov 1925 It was designed 2U-B3 - second training plane with an engine BMW-3 liquid-cooled power 185 l. from. It provides for the possibility BMW-IV engine installation 240 l. from., then the plane could be seen as a transitional. 2U-B3 good aerodynamic different forms, well-designed. Its construction was completed in February 1926 of the year, and in March began testing.
However, there will be new requirements for machines of initial training forced to treat the plane as a transitional, in connection with which it was renamed F-1. Tests confirmed the good performance characteristics of the P-1 (2U-B3), the report of flight tests, in particular, It noted, that "the implementation of a corkscrew sluggish, reminiscent of a steep spiral ". It was ordered by a series of these machines, but the construction did not take place due to another change in the requirements for the transition aircrafts: at the direction of P. AND. Baranova, then chief of the NGO UWS, in the transitional plane must be set armament, so he could use both as a combat training machines, and lightweight housing scout. Thus was armed version n-1 with the BMW engine-IV, and then n-2 to the motor M-6.
By the middle 1925 it was decided to build the initial training aircraft with an engine capacity of about 100 l. from. anticipated, that such an engine will soon be able to create a domestic design teams. 27 September 1925 year Aviatrest letter notified Polikarpov, that "the primary training aircraft starts projected by special order in connection with the construction of a new engine". However Polikarpov before this letter performed some preliminary sketch of this type of aircraft projects.
By the middle 1926 design team of the year, A headed. D. Shvetsov (factory number 4) and n. R. Brilingom (US), It managed to build motors M-11 and M-12 and the start of their trials. Initially, the scales tilt toward M-12, in this connection 3 July 1926 year Aviatrest officially ordered to begin designing the U-2 training aircraft under this engine. Technical requirements for the machine were formulated NTC Air Force and countersigned by the Jets Section C. AT. Ilyushin 15 July 1926 of the year. Their development was actively involved as a member of the Air Force NTC itself H. n. Polikarpov. The requirements, in particular, stipulated, the maximum flight speed should not exceed 120 kmh, and landing - 60 kmh, the aircraft should be only biplane and built from materials available in the USSR.
Polikarpov in the development of the project tried to student and the instructor's seat is located closer to the center of gravity (Unlike aircraft 2U-B3). Particular attention was paid to ease of piloting aircraft. To reduce operating costs and manufacturing the upper and lower wings have the same structure, provides interchangeability. Shape of the wing and tail were made in terms of rectangular for ease of manufacture, that distinguished the first copy of all subsequent experimental and serial options U-2. it, of course, worsened aerodynamics, but owing to low (even in those days) requirements to the maximum speed was considered acceptable.
The report noted Aviatrestu Polikarpov: "The airplane first introduced significant improvements in operationally: mobile foot control, sliding seat, turn off the foot control and manual control, interchangeable ailerons, elevators, etc. ".
6 October 1926 , the preliminary draft was reviewed at a meeting of the Technical Council Aviatresta. The decision noted, that "the overall direction for the design Y2-M12 aircraft, adopted land department, recognize the right " (In those years CB H. n. Polikarpov existed on the Rights of the department of land aircraft construction CDB Aviatresta). However, it was ordered to transfer the fuel tanks of the fuselage on the upper wing and bring them out of the center section. Polikarpov objected to this item, counting, that such an arrangement fuel tanks worsen the aerodynamics of the wing, but I could not do anything.
The layout of the U-2 was built to 5 February 1927 , and immediately began to build, and the first copy machine. However, the full clarity with the motor has not yet been. M-12, which Aviatresta management to make major bets, He broke down on the stand. Earlier in the decision of 2 February 1927 , the Technical Board Aviatresta made a proposal to explore the possibility of installation on the U-2 foreign engines, "Lucifer" in power 100 l. from. and "Salmson" in 120 l. from., a copy of which was in the Soviet Union in various institutions.
By the end of March, it became clear, that "Lucifer" had in Serpukhov aviation school was established on the snowmobile and broken at run. "Salmson" in the US also stood on snowmobile, I worked more 150 hours and was thoroughly worn out. Therefore, in late April 1927 of the year. Aviatrest instructed to set the first prototype design M-11 A. D. Shvetsova, who at that time still passed bench tests, but it did not pass the state. 23 June 1927 , the aircraft was put into airfield.
Testing began with 24 June 1927 of the year. It soon became clear, that M-11 in flight oil overheats, often there are failures. Actually carried out flight tests and operational development of not only the aircraft, as engine. Aviatrest given urgent instructions to install on V-2 engine M-12, but M-12 to bring an appropriate degree of reliability and could not. Jointly by Polikarpov and Shvetsova many disadvantages M-11 still persists. 15 September 1927 , the aircraft was transferred to the state tests in the Air Force Institute. They showed, The car has good flight characteristics, including snap and generally meets the requirements of the Air Force, except for the climb. In the second instance H. n. Polikarpov significantly improved aerodynamics, putting elliptical wingtips and tail. Thick wing profile "Prandtl-R652" was replaced by a thinner profile, developed aerodynamics CB H. n. Polikarpova, because TSAGI suitable profile was not found. To improve the handling characteristics supplied enlarged rudder. Several car eased to a reasonable level. Some data suggest that, that the second copy, fully reflects the views of a similar aircraft Polikarpov, designed in conjunction with the first, but for various reasons we have decided not to transfer production to the completion of first instance trials. However, Projects were very close: the same step ribs, frames, the same design of the basic elements. Draft project was approved by the second instance 28 February 1928 of the year, after the start of the test.
test, who conducted the pilot Gromov January 1928 of the year, We showed excellent flight performance U-2. Already 29 Martha 1928 Air Force, the NTC decided to build a pilot series of U-2 6 copies of the factory number 25 for pilot operation of flying schools. TO 29 October 1929 , this factory built 25 U-2, of which passed to the customer 19 machines.
In the autumn 1928 , the U-2 and several other Soviet aircraft were exhibited at the 3rd International Air Show in Berlin.
By the end 1928 year experienced a series of tests were completed, after which at the Leningrad plant № 23 It has begun the deployment of mass production. Two first U-2 were released in May by the 1929 of the year. From May to September 1929 Was built 19 U-2. In the future, production has developed very quickly. for example, totally agree 1933 23rd year the plant produced 1508 machines. Serial planes different from the second instance, basically, altered hood.
Design
Under the scheme of the plane U-2 - single-engined biplane double bracing structure with an air cooling engine M-11 power 125 l. from.
Fuselage
Rectangular cross-section fuselage is made of wood as a spatial bracing Farm, coated plywood front, and behind - the canvas. The sanitary modified fuselage U-2 was designed to 2 seats (one prone and one sitting), Besides, 2 a person placed on the lower wing in the removable cab structure Bakshaeva or Shcherbakova engineers. The total length of the aircraft - 8170 mm. Empty weight training aircraft on wheels - 752 kg, installation of skis to increase the weight on the 6 kg. Normal Flight weight training aircraft was 1012 kg, bomber - 1400 kg, sanitary aircraft - 1472 kg.
Wing
Four identical in length and area of wooden bearing surfaces were odnoprolotnuyu box wings, braced belts and I-shaped struts. Wing box was given a transverse angle 5 degrees. The upper wing was made to forward 800 mm. Swipe upper wing - 11420 mm, lower - 10655 mm, area - 35,4 m².
tail, stabilizer, chassis
Stabilizer and tail were removable, area 5,05 quarter. m (Stabilizer with rudders) and 1,67 quarter. m (keel with rudder). aircraft undercarriage – trohstoechnoe, fixed landing, the amortization of the rubber cord.
ROTOR
U-2 is set five-cylinder, air cooling the motor M-11D maximum power at the surface 125 l. from., on high 1670 m - 90 l. from. Fuel tank total capacity 125 liters placed behind the firewall, oil tank capacity 21,5 liter engine mounted behind. Fuel capacity ensures non-stop flight to the distance 350-400 km. Engine starts when turning the hand or recoil damper, and avtostartorom. maximum speed - from 130 to 150 kmh, cruising - 100-120 km / h, landing - 60-70 km / h, ceiling - 3800 m, run and run - 100-150 m.
Production and operation
U-2 had a wide range of applications in agriculture, communications and other fields. there were staff, sanitary, designed for aerial photography, passenger, Float and many other modifications. AT 1932 It was developed combat training variant of the U-2 (U-2p), which could take six 8-kilogram bombs on holders, and shooting point was located in the rear cockpit of the machine with a machine gun PV-1.
Since the beginning of the Great Patriotic War, the production of the U-2 was organized at the aircraft factory number 387. The available options standard U-2 began to remodel into the lungs night bomber. Refinement was carried out in the Polikarpov OKB, and in industrial plants and in the army forces technical staff combat units and aircraft repair shops. Consequently combat U-2 structure had a large number of different variants. Bomb load varied from 100 kg 350 kg.
Flight quality U-2, depending on whether, the purposes for which used airplane, and what changes were made to its equipment, fluctuated. But in all cases the aircraft remained reliable, easy and obedient in management. U-2 could make takeoff and landing at the smallest ground and even on unprepared sites. To improve the handling characteristics on the plane was applied enlarged rudder.
In the 1930s, we produced and repaired the U-2 Leningrad factories number 23 and number 47. In connection with the development of new types of aircraft factory number 23, production of the U-2 was transferred to a new aircraft plant number Leningrad 387, which from April 1941 the year began to produce U-2.
During the Second World War U-2 and its modifications were made at the factory number 387, evacuated to Kazan, as well as in factories: № 464 (g. Dolgoprudny), № 471 (g. Shumerlya), № 494 (g. Kozlovka). In Moscow, an aircraft factory number 51 built modified U-2 planes: the poplavkah, and special - for conducting radio air.
After the death of H. n. Polikarpov in 1944 by airplane after its creator renamed Po-2. U-2 was built to standard 1953 of the year, Was built 33 000 machines.
Modifications to the aircraft U-2 (In 2)
In-2LSH - a light attack aircraft; a large number of pre-war aircraft were converted to this standard; armed with one machine gun caliber ShKAS 7,62 mm, I had an attachment to 120 kg bombs, plus rails for four missiles RS-82.
In-2LNB - light night bomber, produced since 1941 g.
U-2p - the main plane connection the Soviet Air Force, also used senior officers; more 9000 copies were in service in the 1945 g. under the new designation In 2VS.
In-2AP - modification farm on which was mounted aeroopylitel spraying of fertilizers and pesticides.
Hydroplane U-2M (More 2M)
U-2M - released a small series seaplane.
U-2SP - Triple (2 passenger) special application plane.
U-2L - variant with a comfortable enclosed cabin.
U-2S (C-1) - aircraft sanaviatsii compartment for a patient on a stretcher in the fuselage (1934-1938's., M-11A).
C-2 - the second version of the aircraft sanaviatsii (1940-1945's., M-11D).
combat application
U-2 had a number of advantages. At first, he was extremely simple and cheap in production and operation, easily repaired, It is making its production extremely profitable to the USSR, which it is cheap and simple technology were of particular significance. Secondly, the plane was very easy to drive and even an inexperienced pilot could fly freely in it. U-2 "forgave" the pilot many mistakes, that on another plane would inevitably lead to an accident. For this reason, it was the U-2 was the main training aircraft of the Soviet Air Force. for example, the car was almost impossible to enter into a tailspin; when, if the pilot let go of control surfaces, the plane began to plan with a speed reduction 1 meter per second, If the bottom of the smooth surface provided, I could sit on her own. Finally, U-2 could make landing and rise into the air from the very soil "Piglet" - a very small place for takeoff, It is making it ideal for communicating with the guerrillas. Thirdly, U-2 had a low rate and therefore could fly at low altitudes, while a high-speed aircraft risked while crashing into the hills, trees, the terrain. Luftwaffe pilots soon learned, that maize is extremely difficult to bring down because of two main factors: U-2 pilots flew at treetop, where they were difficult to distinguish and difficult and also stalling speed German fighters such as e.g. Messerschmitt Bf 109 and Focke-Wulf Fw 190 It was similar to the maximum rate U-2, that complicates the task of the U-2 retention in the range fighter arms for sufficient time.
This allowed us to use the car for shturmovok and bombing enemy positions, Although sorties made, usually, at night, as the day the plane became easy prey for enemy fighters could be shot down by ground fire even from small arms. All these advantages of the U-2 led to, it is widely used in the Soviet Air Force as a night bomber, aircraft reconnaissance and communications.
AT 1943 g. German reconnaissance planes often clashed with Russian aircraft communications in the areas of railways, serve them as a good guide. Dirty gray-green color perfectly disguised with such machines, particularly in adverse weather conditions, when the sky was overcast. they can be identified in clear weather at a sharply delineated forms.
Russian pilots skillfully used landmarks to plot. On such planes rear cabin often equipped with a machine gun on a rotating turret to protect against attacks from German fighters tail portion. Upon detection of German fighters, Russian pilots tried to leave sharp maneuvers, hide in the forest glades, hide behind trees or villages. The Germans managed to shoot down such aircraft, Only if they are overtaken Russian pilots by surprise, going from the tail and sharply reducing the height and speed.
The personnel of the 45 th Guards Fighter-Bomber Regiment and civilians in the plane U-2, received battle damage. Central front
night-intruder
The first U-2 used as a bomber pilot GVF Southwest Air Group II. FROM. Bevz, fought near Odessa. It remains anonymous, It was carried out at this retrofit aircraft bombovooruzheniem, or small fragmentation bombs and grenades reset is done manually; and who are reset - by the pilot or scorer, We are in the second cabin.
U-2 is widely used for so-called "harassing raids" at night on frontline location of enemy troops.
based U-2 space were at a distance of up to 150 kilometers from the front line and to make them intense flights often been uncomfortable. Therefore, all the combat work night bomber regiments were performed jump airfields, located in 20-35 km from the best. In the afternoon the grounds were empty, and in the evening they flew planes.
The main ammunition, discharged from the U-2, were high-explosive bombs FAB-100 and FAB-50. It was suspended on a bomber or two "hundred", or 4 caliber bombs 50 kg. Besides, when bombing used vials, Curb mixture "KS". They were charged in plywood cassette with fuse. At a predetermined height after resetting fuse breakdowns, cassette was opened and the balls scattered over a large area, burning everything to the ground in the fall. Besides, used incendiary bombs ZABTOOtsh (with termite balls) and TB-50 (with solid fuel). Of fragmentation bombs were used SA-2.5; AO-10 and the 1943 AO-25-35, particularly active in the beginning of the war, and when flying over long distances. Of non-lethal weapons were used lighting bomb SAB-100 and agitation AGB-100.
Suspension of 50-kg bomb FAB-50 bomb racks on the U-2 aircraft
One tactic is, that light bombers approached the target with small gas engines installed or ultra low altitude, thus they remain invisible to the weapons of the enemy air defense until the last moment.
In an effort to avoid losses from anti-aircraft fire, in the U-2 shelves we tried a new tactic. head aircraft, wingman pilot with excellent technique piloting, He provoked the German defense on fire. When lit searchlights and anti-aircraft guns opened fire on the maneuver U-2, the crew of the second bomber came on defense position from the rear, priglušal engine and, going with reduction, He dumped on prozhektoristov gunners and fragmentation bombs or fired from their ShKAS. AT 271 In a, Besides, It has been developed and used in combat aircraft installation PC for firing at the enemy anti-aircraft fire. After such "processing" bombers, followed the lead pair, We had less difficulty over the target.
Despite the small bomb load, Similar bombardment had a certain effect. With low altitude bombing produced with very high precision, even though the dark and primitive sighting means. After dropping bombs bomber tried to leave quickly, gaining maximum speed.
The results of combat activities of the U-2 was impressive. For example, navigator link 97th Guards Night Bomber Aviation Regiment Guard Lieutenant Hero of the Soviet Union Vasily Kiz made 640 sorties, detonated 27 warehouses with fuel and ammunition, ruined 7 bunkers, observation post, 168 buildings and structures, destroyed 24 car and 4 aircraft on ground. The individual pilots have on his account more 800 sorties, and some (Hero of Soviet Union Irina Sebrova) - more than a thousand.
Handling wounded in a Red sanitary C-3 (modification of the U-2 aircraft for the transport of the wounded) for evacuation to the rear
In a particularly tense night to provide ground crews 12 sorties each U-2. The number of flights depend on the duration of the dark time of day.
According to the memoirs of Soviet pilots, flew U-2, After completion of the aircraft factory in 1942 , the bomb load was significantly increased - up 250 kg (in some cases - up to 500 kg), departures are sometimes made to fourteen times a night. «Kaffeemühle» (coffee mill), "Sewing machine" (sewing machine, because typical engine sound) - Wehrmacht soldiers so called U-2, gives a lot of trouble for the enemy in the war area.
U-2 can operate in the most adverse weather conditions. So, in February 1944 year in extremely difficult weather conditions, the U-2 anti-tank bomb hit a convoy of armored vehicles of the enemy near the town of Korsun-Shevchenko. As a result of the air strike was foiled the last attempt of the Germans to break out.
During the fighting on the Taman Peninsula to combat "Soviet women bedside lamps" was transferred to an entire squadron of fascist aces. For every German pilots downed aircraft received the highest award - the "Iron Cross".
Soviet pilots in the U-2 plane cockpit before flying on a combat mission.
Spy plane and a plane connection
But the basic usage, of course, were reconnaissance aircraft and communication functions. There was also a version of the aircraft, and sanitarian.
With the ability to take off from any site, the aircraft was widely used when working with the guerrillas. He is actively used for evacuation. In February 1943 , during the "Osveysky tragedy" on the U-2 was exported to several dozen passengers per flight (basically, children).
Besides, U-2 planes used to reset the small parachute sabotage and reconnaissance teams.
U-2 was actively used in the Korean War as a light bomber and attack aircraft.
Women lotchitsy
In autumn 1941 the formation of the air units were started in the Soviet Air Force, staffed by women.
One of the female air regiments was armed planes U-2:
– 46-and ("Taman") Guards Night Bomber Aviation Regiment
23 lotchitsam, fought on the U-2, It was awarded the title Hero of the Soviet Union.
Group of light bombers, U-2 271st Night Bomber Division is flying on a mission. The division commander Colonel Konstantin Pavlovich Tales
The performance characteristics of the U-2 (In 2)
– Crew: 2 people.
The dimensions of the U-2 (In 2)
– The length of the plane: 8,17 m
– Wingspan: 11,4 m
– Height, m: 3,10
– wing area, m2: 33,15
Weight U-2 (In 2)
– Empty weight, kg: 770
– Mass normal takeoff, kg: 1350
Speed U-2 (In 2)
– full speed: 150 kmh
– Cruising speed: 131 kmh
Practical ceiling U-2 (In 2)
– 3820 m
Range of flight U-2 (In 2)
– 430 km
Engine U-2 (In 2)
– engine's type: 1 PD M-11A
– Power: 110 l. from.
– fuel capacity: 90 kg
Armament U-2 (In 2)
– a 7.62mm gun ShKAS
– explosive bombs FAB-100 and FAB-50 was suspended or two "hundred", or 4 caliber bombs 50 kg.
– firebombs ZABTOOtsh (with termite balls) and TB-50 (with solid fuel)
– fragmentation bombs AO-2.5; AO-10 and the 1943 AO-25-35
Photo U-2 (In 2)
Building aircraft crews U-2 at the airport in their cars
Soviet aircraft engine produces service M-11 on the U-2 plane
Pilot U-2 crawler chassis Chechubalina
Loading the wounded during the Soviet U-2 plane to evacuate from the south shore of the lake Siwash. The aircraft is equipped with cassettes Bakshaeva, Holds one wounded on stretchers
The Soviet passenger airplane-connected U-2br (special applications) one part of the CAF (Civil Aviation), mobilized for flights to the partisans. On board the plane the inscription "Partizan"
Soviet pilots ready to fly a bomber Y-2LNB
