Three examples of the Boeing B-29 arrived in late 1944 (examples of which had made emergency landings in Russia during 1944 in the course of operations against Japan); one being dissected and analysed, and the other two used as crew trainers and evaluation.
The Soviet Union built the Tu-4 by copying them as a virtual exterior clone of the B-29 but with significant interior modifications. It was a heavier aircraft and did not possess either the pressurised tunnel linking the forward to midships crew locations or the integral fuel tankage of the B-29. The first of a 20-aircraft pre-production batch flew on 3 July 1947.
Placed in service in 1948, series production terminated after over 400 aircraft had been delivered in 1952, by which time the Tu-4 was in large scale service with the Soviet DA (Long-Range Aviation), being accorded the NATO reporting name ‘Bull’. Some were used as wingtip-to-wingtip inflight-refuelling tankers, others as conventional HDU-equipped tankers.
It is reported that about 1200 were built.
The type was exported to China where some were re-engined with Ivchenko AI-20 turboprops and were sporadically used into the 1990s as AEW and drone launching platforms.
Engines: 4 x ASh-90, 1705kW Max take-off weight: 61300 kg / 135144 lb Empty weight: 35000 kg / 77162 lb Wingspan: 43.1 m / 141 ft 5 in Length: 30.2 m / 99 ft 1 in Height: 8.5 m / 28 ft 11 in Wing area: 161.5 sq.m / 1738.37 sq ft Max. speed: 570 km/h / 354 mph Ceiling: 11000 m / 36100 ft Range w/max.payload: 5000 km / 3107 miles Crew: 11 Armament: 5 x 23mm cannons Bombload: 5000kg
The origin of the Tupolev Tu-2 lay in the ANT-58, ANT-59 and ANT-60 light bomber prototypes that came from the design bureau of Andrei N. Tupolev during 1938-40. Powered by two 1044kW Mikulin AM-37 V-12 engines, the ANT-58 made its first flight on 29 January 1941.
The ANT-60 was re-engined with the big and powerful 1104kW M-82 radials because of the relative unreliability of the AM-37s. The result was the definitive Tu-2 bomber that was to see service with the V-VS during the last year of World War II and well into the 1950s.
Soviet industry was still in a state of upheaval following the years of 1941-2, when the German army struck deep into Belorussia and the Ukraine. The Tu-2 was too complicated an aircraft for the conditions prevailing, and after many months in which the Tu-2 was modified and simplified for the mass production lines, the Tu-2S (Seriinyi, or series) appeared, flying for the first time on 26 August 1943. A small number of Tu-2s had previously been passed to front line regiments in September 1942, where their performance, armament and bombload had received general enthusiasm.
By January 1944 the first production Tu-2 and Tu-2S bombers had been passed to the regiments of the V-VS, but it was not until June of that year that Tu-2s saw action on a large scale. The sector was the Karelian (Finnish) front in the north where the V-VS forces, under the overall command of General A.A. Novikov, numbered 757 aircraft of the 13th VA (Air Army), the V-VS KBF (Red Banner Baltic Fleet) and the 2nd GVIAK (guards fighter corps). Of the 249 Tu-2 and Petlyakov Pe-2 light bombers in the Soviet order of battle, many came under Colonel I.P. Skok’s 334th Bomber Air Division which subsequently received a citation for its work. Reconnaissance work was now being carried out by Tu-2D and Tu-2R aircraft with modified mainplanes, nose glazing, and capacity for vertical and oblique cameras. Wartime production of the Tupolev Tu-2 and its sub-types amounted to 1,111. As a bomber it did not come into its own until the autumn of 1944. However, as German resistance stiffened on nearing the eastern borders of the Reich V-VS bombers, including Tupolev Tu-2s, were called up to attack strongpoints at Kustrin and other fortified ports and cities. September 1945 saw many Tu-2s in action against the Japanese Kwantung Army in Manchuria before the final surrender.
Tu-2
Tupolev was awarded a Stalin Prize for his Tu 2 medium bomber, the only wholly new Soviet wartime aircraft to go into production.
Tu-2S Engines: 2 x ASh-82FNV, 1380kW Max take-off weight: 11360 kg / 25045 lb Empty weight: 7474 kg / 16477 lb Wingspan: 18.86 m / 62 ft 11 in Length: 13.8 m / 45 ft 3 in Height: 4.55 m / 15 ft 11 in Wing area: 48.8 sq.m / 525.28 sq ft Max. speed: 550 km/h / 342 mph Ceiling: 9500 m / 31150 ft Range: 1400 km / 870 miles Crew: 4 Armament: 2 x 20mm cannons, 3 x 12.7mm machine-guns Bombload: 4000kg
An attempt to produce a radar-equipped three-seat long-range night and all-weather fighter also suited for the escort mission, the ANT-63P, alias Tu-1, was one of a number of progressive developments of the ANT-61 (Tu-2S) bomber. Initially powered by two 1,900hp Mikulin AM-39F 12-cylinder liquid-cooled engines, the ANT-63P (the suffix letter indicating Perekhvatchik, or “Interceptor”) carried a fixed forward-firing armament of four 23mm cannon, two in the wing roots and two in the lower forward fuselage. The nose was intended to accommodate a PNB-1 Gneiss-1 airborne intercept radar based on the German FuG 220. First flown on 30 December 1946, the ANT-63P attained 680km/h and demonstrated a range of 2500km. Official interest in piston-engined fighters was waning by this time, and although the ANT-63P was re-engined with 1,950hp Mikulin AM-43V engines driving four-bladed propellers, being tested in this form in December 1947, no production was undertaken.
ANT-63P Engines: 2 x AM-43V Max take-off weight: 14460 kg / 31879 lb Wingspan: 18.86 m / 62 ft 11 in Length: 13.60 m / 45 ft 7 in Wing area: 48.80 sq.m / 525.28 sq ft Max. speed: 641 km/h / 398 mph Range: 2250 km / 1398 miles
Ordered in December 1934 as a single prototype under the designation DI-8, the ANT-46 was a two-seat fighter (Dvukhmestny istrebitel) derivative of Aleksandr Arkhangelsky’s SB high-speed bomber (ANT-40). Featuring a lightened structure and powered by two 800hp Gnome-Rhone 14Krsd 14-cylinder air-cooled radial engines, the ANT-46 was intended to carry two 100mm Kurchevski APK-100 recoilless guns as its primary armament, these weapons being buried in the outer wings between the ailerons and the flaps, and projecting fore and aft. In addition, it was intended to mount a battery of four 7.62mm guns in the extreme nose, but these were not carried by the prototype, which featured a glazed nose generally similar to that of the SB.
First flown on 9 August 1935, the ANT-46 was actually flown before the ANT-29, the factory flight test programme being completed successfully in June 1936, but state acceptance testing was not undertaken as official interest in the recoilless gun – for which the ANT-46 had been specifically developed – had terminated with the arrest, in February 1936, of Leonid Kurchevski.
Max take-off weight: 5553 kg / 12242 lb Empty weight: 3487 kg / 7688 lb Wingspan: 20.30 m / 67 ft 7 in Length: 12.24 m / 40 ft 2 in Wing area: 55.70 sq.m / 599.55 sq ft Max. speed: 388 km/h / 241 mph Range: 1780 km / 1106 miles
In December 1934, Tupolev was asked to design a naval heavy bomber (Morksoi Torpedonosets Bombardirovshik = naval torpedo bomber = MTB). With his seaplane specialist Ivan Pogosski dead, he gave the project to Aleksander Golubkov who came up with a more conventional design than the earlier ANT ‘hydroplanes’ – a single hull with a high-wing profile, made entirely from duraluminium. It was an amphibian with a retractable wheeled undercarriage, and the floats, mounted near the wingtips on struts, were load-carrying. Powerplants were four Gnome-Rhone 14Krsds, which gave 810hp each, and were mounted in the wing leading edges. The wing shape resulted in the ANT-44, as the project was designated, being called the Chaika (Seagull).
Construction of the prototype began on 4 October 1935, and the aircraft was manufactured with smooth sheets of duraluminium, which were now becoming available in place of the former corrugated ones. The work was carried out in the TsAGI-ZOK factory N156. It was completed in March 1937, and brought by road to Khodinka, from where it made its first flight on a fixed wheeled undercarriage (because the retractable mechanisation was not yet ready) on 19 April 1937. Its pilot was Timofei Riabenko. State tests were conducted with the undercarriage fixed down; maximum speed was measured at 355km/h, maximum take-off weight at 18,500kg, and range with a bomb or torpedo load of 2,500kg was 2,500km. The state tests were completed in July.
A second aircraft was completed in June 1938. By now the first had its undercarriage modified to retract, while the second aircraft had a retractable one from the start. It had 840hp Mikulin M-87As fitted and was dubbed the ANT-44bis or -44D.
By September, both aircraft were taken on service with the Soviet Navy, as the MTB-2A.
No production was ordered, and they served some operations in the Great Patriotic War from bases in the Black Sea. Led by Ivan Sukhomlin, the MTB-2As were used to bomb oil refineries in Bulgaria and Romania, both then under Nazi occupation.
Before the Soviet Union was invaded by Germany, Ivan Sukhomlin had earned four world records, with the ANT-44bis. In June 1940, he set several records lifting different loads to record altitudes for amphibians, and on 7 October he achieved a record for amphibians by carrying a two-tonne load over a 1,000km closed circuit at an average speed of 241.999km/h. Although this record was not acknowledged by the FAI until after the war, it stood unbeaten until 1957.
MTB-2A Engine: 4 x M-87 Max take-off weight: 21500 kg / 47400 lb Wingspan: 37.0 m / 121 ft 5 in Length: 24.0 m / 79 ft 9 in Height: 9.0 m / 30 ft 6 in Wing area: 144.7 sq.m / 1557.54 sq ft Max. speed: 350 km/h / 217 mph Cruise speed: 250 km/h / 155 mph Ceiling: 7200 m / 23600 ft Range: 4500 km / 2796 miles Range w/max.payload: 2500 km / 1553 miles Crew: 4-5 Armament: 6 x 7.62mm machine-guns Bombload: 2000kg
The two ANT-40 light bomber prototypes of Andrei N. Tupolev’s design bureau first flew in October 1934. The all-metal construction, enclosed cockpit and retractable landing gear were then comparatively novel features. The ANT-40’s maximum speed of 325km/h at operating height was faster than the biplane interceptor fighters that equipped most of the peacetime air forces.
Tupolev SB-2 Article
Entering production in 1936, the initial production version as selected for export and service with the V-VS was based on the second prototype, and was known as the Tupolev SB-2 (skorostnoi bombardirovshchik, or fast bomber). The engines were two 830 hp / 619kW licence-built Hispano-Suiza 12Ybr, termed M-34 by Soviet industry, and initially they were fitted with two-bladed fixed-pitch propellers.
An aircraft of this type secured an official FAI record in 1937 for carrying a 1000 kg / 2200 lb payload to an altitude of 40,177 ft.
The first SB-2s were passed to the V-VS’s bomber aviation regiments in February 1936, and in October of that year the first of 210 were transferred with Soviet crews to Spain to fight on the side of the Republican air force against the insurgent Nationalists.
The SB-2 was the first Soviet warplane delivered to the Republicans, arriving from October 1936 in an effort to provide an offensive type which could take the air war to the advancing Nationalists. The variant delivered was the initial SB-2 production model powered by M-100 or 641 kW (860-hp) M-100A inlines driving fixed or variable pitch propellers respectively. Estimates for the number of SB-2s delivered vary from 93 to 210, and these aircraft were amongst the best fielded by the Republicans: their performance and defensive firepower allowed most Nationalist fighters to be outrun or outfought. Some 19 operational SB-2 bombers fell into Nationalist hands at the end of the war, and claims on the type amounted to 14 by the Nationalists, a similar number by the Germans, and 48 by the Italians.
Over Spain the performance of the SB-2 caused considerable concern to the Nationalist fighter units which were equipped with Heinkel He-51 and Fiat CR.32 biplanes, and the urgent call went out for fighters of better speed and climb properties.
The production of the SB-2 bomber and the conversion of the units required the development of a training model that would facilitate the preparation of the crews. This need was solved in 1937 with the installation of a second flight control in the navigator’s position in an SB-2M-100A, but the results of the tests showed that this decision made the navigator’s work more complex and worsened the aerodynamics of the model.
At the time SB-2s were passed to the Chinese Nationalist air force to fight aganst the Japanese, and to Czechoslovakia, where the type went into licensed manufacture as the B.71 bomber.
1934 Avia development was helped engineer A. A. Archangelskij from the ANT 40.2 SB – 2 (Skorostnyj Bombardirovščik). The Czechoslovak Air Force had 60 of these aircraft and one at a research institute. Because all three Aeroplane Works within a range of German bombers were, a new plant was built at the village of Kunovice in South Moravia. Two batches of the B-71 bomber – 40 and 26 machines respectively. 30 SB-2s were purchased by the Czechoslovak Republic from the Soviet Union and in 1936 also their licence. Serial production started at Avia and by the German occupation not a single was finished, the unfinished aircraft were completed by the Germans. Avia Works built forty-five that were used by Luftwaffe or sent to Bulgaria. The B-71 Katyushkas were powered by Czech-made 680 Avia-Hispano Suiza engines and were able to accommodate the bombload of 600 kg under their wings.
The Avia-built B-71 were fitted with a new tubular radiators and gained 15 kph. The idea was copied by the Soviets and brought into use in the SB-3. After the German occupation the B-71s were converted to target towing configuration.
Avia B-71
In general the SB-2 performed well until faced with sterner fighter opposition, which occurred over Spain in 1938 and in particular over Finland during the Winter War of 1939-40, when many were shot down. Steps were taken to improve performance by installing the 641kW M-100A engine with variable-pitch propellers. Increased fuel capacity and two 716kW M-103 engines were installed in the Tupolev SB-2bis, the performance of which was improved by three-bladed VISh-22 propellers.
The study of the 3-wheeled undercarriage on a twin-engined aircraft, nicknamed “pterodactyl”, was carried out in 1940. Using a special frame under the center section the pilot, Mark Galley, repeatedly landed the aircraft with a vertical speed of up to 4.8 m / s. The landing gear was fully tested. For study of the “shimmy” phenomenon the ran over a log put across the runway. The original size of the front wheel was 470×210 mm, but changed to 600×250 mm.
SB “Pterodactyl”
The front wheel was 4.65 m from the center of gravity and the main struts moved back beyond the center of gravity 520 mm, the wheels remained the same – 900×300 mm.
SB “Pterodactyl”
A frame was used to rearrange the main undercarriage in order to determine their optimal location. The aircraft was tested with a flight weight of 6000 kg, the wing load was 106 kg/sq.m and flight speeds up to 220 – 230 km/hr. Landing speed with flaps was 140 – 150 km / h, without flaps 190 km/h.
SB “Pterodactyl”
Tests were summarized and published in February 1941, turned out to be very popular. It is believed that the research results were useful in developing a new generation of Soviet aircraft with a front support wheel.
The PS-41 was a transport variant with a ‘solid’ nose and gun positions eliminated.
In addition to the PS-40 and PS-41 transport versions the SB-RK (Arkhangelskii Ar-2) was a modified SB-2bis dive-bomber with reduced wing area and powered by two supercharged M-105R engines. The SB-2’s record as a day bomber came to an abrupt end during the fierce fighting following the German invasion of the USSR on 22 June 1941. Those that were not destroyed on the ground ventured into the air on numerous missions over the front line, and paid a heavy price to the Luftwaffe’s Messerschmitt Bf 109F fighters. Thereafter the SB-2 and SB-2bis bombers were relegated to night work with the V-VS and the Soviet naval air arm.
Production amounted to 6,967 of all marks.
Variant: Tupolev SB-RK / Arjanguelsky Ar-2 Arjanguelsky SB-B Arjanguelsky USB
SB-2 Three-seat light/medium bomber Span: 20.33m (66ft 8.5 in) Length: 12.57m (41ft 2.75in) Powerplant: 2 x Klimov M-100, 559kW (750 hp) Armament: 4×7.62-mm (0.3-in) mg Bombload: 1000 kg (2,205 lb) Max T/O weight: 5628 kg (12,407 lb) Max speed: 244 mph at 17,060 ft Operational range: 777 miles
SB-2bis Engine: 2 x M-100 Max take-off weight: 5732 kg / 12637 lb Empty weight: 4060 kg / 8951 lb Wingspan: 20.3 m / 67 ft 7 in Length: 12.7 m / 42 ft 8 in Wing area: 52.0 sq.m / 559.72 sq ft Max. speed: 420 km/h / 261 mph Cruise speed: 360 km/h / 224 mph Ceiling: 6600 m / 21650 ft Range: 1600 km / 994 miles Range w/max.payload: 1000 km / 621 miles Crew: 3 Armament: 4 x 12.7mm machine-guns Bombload: 1500kg
SB-2bis Engine: 2 x M-103, 990 hp Wingspan: 70 ft 6 in Length: 41 ft 6 in Max take-off weight: 14,330 lb Empty weight: 9436 lb Max. speed: 280 mph at 16,400 ft Cruise speed: 360 km/h / 224 mph Service ceiling: 27,890 ft Range: 1430 miles Crew: 3 Armament: 4 x 7.62mm machine-guns Bombload: 1320 lb
Developed from the uncompleted Tupolev ANT-36 (DB-1), a single-engined long-range bomber based on the ANT-25, the Tupolev ANT-37 (DB-2) long-range bomber was developed by Sukhoi’s design brigade under Tupolev’s overall control.
The Tupolev DB-2 (ANT-37) long-range bomber, designed in the autumn of 1934, could carry a 2,200 lb bomb load over a range of 3,100 miles at a speed of 155 m.p.h.
The prototype flew on 16 June 1935, powered by two 597kW Gnome-Rhone 14Kdrs engines, broke up in mid-air in August 1935 owing to buffeting of the tail unit. Test pilot K. Popov and the flight engineer managed to bale out, but a third crew member did not survive the crash.
The second prototype, powered by licence built Gnome-Rhone M-85s, was tested and refined throughout 1936. It was then transferred to the Nauchno Issledovatelsky Institut Voyenno-Vozdushnykh Sil (NII V-VS – Scientific Research Institute of the Air Force) for State tests, which continued until mid-1937. It was admitted that the DB-2 was inferior to Ilyushin’s DB-3 bomber in several respects, particularly maximum speed (200 m.p.h. and 248 m.p.h. respectively), so further development was abandoned.
When the second DB-2 prototype had completed its State tests it was proposed that it be handed over to the Tsentralniy Aero-Gidrodinarnicheskiy Institut (TsAGI, the Central AeroHydrodynamic institute) for further refinement and additional flight tests. Another DB-2 was completed and handed over to a Soviet Air Force (V-VS) unit for training personnel in endurance and long-range flying.
Having undergone modification, the second prototype was provided for the long-distance flight to be undertaken by Grizodubova, Raskova and Osipenko. it was completely stripped of armament, fitted with additional fuel tanks to ensure a maximum range of 4,350 miles and given new flight instruments and 950 h.p. licence-built Gnome-Rhone M-86 engines.
The DB-2D was followed in turn by the DB-2B or ANT-37bis, of which only three were built as record breakers/research aircraft after rejection of the design in favour of the llyushin DB-3.
Once the crew had been trained they started preparing for the non-stop flight. On August 18, 1938, they took off from the Central Airfield at Moscow for another training flight, but at a height of 165ft the aeroplane suddenly jerked down and almost went out of control. After a difficult landing, it became clear that the shortcomings of the first prototype had not been completely rectified. The tail unit had distorted disastrously during takeoff at maximum weight, and the aircraft was no longer airworthy. The technical team therefore began urgent preparation of the third prototype, the last of the three serviceable machines.
The aircraft’s replacement caused deferment of the flight, which in turn led to concern over a successful outcome. Autumn had already set in and weather conditions along the planned route across the Urals and Siberia were deteriorating with each passing day.
The first DB-2B, named Rodina (motherland) was flown to a long-distance women’s record by an all-female crew, covering 5908km on 24/25 September 1938 before making an emergency landing.
Examples survived well into the wartime period, flying for Aeroflot or on research projects.
DB-2bis Engine: 2 x M-86 Max take-off weight: 12500 kg / 27558 lb Empty weight: 5855 kg / 12908 lb Wingspan: 31.0 m / 102 ft 8 in Length: 15.0 m / 49 ft 3 in Wing area: 85.0 sq.m / 914.93 sq ft Max. speed: 300 km/h / 186 mph Ceiling: 8000 m / 26250 ft Range w/max.fuel: 7000 km / 4350 miles Crew: 3
The ANT-36 was a redesigned ANT-25, and the twenty aircraft built for the Soviet Air Force under the military designation DB-1 were actually ANT-36s. This has caused some confusion as the sometimes reported production figures of the ANT-25 are quoted as two (the correct figure) and twenty-two, the total which includes both the -25 and the -36.
The major differences between the two Sukhoi-led programmes was armaments: on two aircraft, the Mikulin M-34R of the ANT-25 was changed for a Junkers Jumo 4 diesel and, later, the Soviet-built AN-1 diesel. But these engines left the DB-1 underpowered and slow, and its limited armaments, low service ceiling and large wing meant it was very vulnerable to fighters, so the planned production of fifty was cut to twenty which were never to see service in the role for which they were intended.
By spring 1936, these twenty had been delivered to the Air Force base at Ismailova, near Moscow. Two of these were fitted with diesel engines, and flight tests indicated that this version could achieve a range of 25,000km. It was planned to circumnavigate the world on the 57°N line of latitude, but the build-up to the Second World War caused the plans to be put aside. The remaining thirty aircraft were not built.
The aircraft was not a military success. Labelled the DB-1, the Air Force soon realised that the almost five years it took to develop had left the aircraft too slow, and that against contemporary fighters it was outclassed and virtually defenceless. But the twenty military aircraft went on to further flight trials; two were fitted with Junkers Jumo diesel engines, as has already been mentioned. Most of the others were used by the TsAGFs BOK, a department headed by Vladimir Chizhevski which was developing pressurised cabins for high-altitude test flights. In 1936, Chizhevski had worked in Kharkov developing pressurised cabins for high-altitude balloons. He lightened the airframe and shortened the span for his first version, the BOK-1. The engine chosen was the M-34RN with a turbocharger fitted to permit a ceiling of 10,000m to be attained. In early trials Piotr Stefanovski reached 10,700m; later, after further lightening of the aircraft, he brought it up to 14,100m. In June 1937, the engine was replaced by the new M-34RNV, fitted with two turbochargers. With some lightening, the aircraft reached heights of over 12,000m.
In 1938, Chizhevski modified another ANT-36 to BOK-7 standard. He substantially modified the cabin, so now the two crew sat with their heads in small doubleglazed domes which rose above the line of the fuselage. It was powered by a M-34FRN and had two superchargers. With this, the Soviet Air Force set its plans for a non-stop round the world flight approximately on the 53° North line of latitude. The programme was headed by Aleksander Filin, one of Chkalov’s crew, and targeted for 1939 or 1940. But Filin was arrested in Stalin’s purge, and executed in 1940. This and the war ended the project.
The Tupolev ANT-35 all-metal light passenger transport prototype was based on the SB-2 bomber, and was flown initially on 20 August 1936. Of low-wing configuration with retractable main landing gear units, it was powered by two 597kW Gnome-Rhone 14K radials, later replaced by Soviet M-85s; its near circular-section fuselage accommodated a crew of two or three and 10 passengers. The improved ANT-35bis prototype was followed by nine series aircraft powered by 746kW M-62IR engines, and the type entered service with Aeroflot as the PS-35, delivered from 1937 to 1939. After June 1941 several were used for liaison and VIP transport, this 20.80m span aircraft having a maximum speed of 372km/h and a range of 1640km.
PS-35 Engines: 2 x M-85 Max take-off weight: 6620 kg / 14595 lb Wingspan: 20.8 m / 68 ft 3 in Length: 15.0 m / 49 ft 3 in Height: 5.9 m / 19 ft 4 in Wing area: 58.0 sq.m / 624.31 sq ft Max. speed: 376 km/h / 234 mph Cruise speed: 350 km/h / 217 mph Ceiling: 7200 m / 23600 ft Range: 1600 km / 994 miles Crew: 2 Passengers: 10
All Aero 