World War II Database

Contributor: Alan Chanter

ww2dbaseThe Petlyakov Pe-8 was the sole modern Soviet four engine heavy bomber to see action during the World War II, making night attacks on targets such as Berlin, Königsberg and Danzig as well as battlefield interdiction raids in support of the Red Army. Designed by a team from the Tupolev Design Bureau led by Vladimir Petlyakov (1891-1942) in response to a 1934 official requirement for a heavy bomber to replace the obsolescent Tupolev TB-3, the project received the internal bureau designation of ANT-42 and initial designation of TB-7 by the VVS - Voenno-Vozdushnye, Sily Krassnoi Armii (Military Air Forces of the Red Army).

ww2dbaseA cantilever mid-wing monoplane of all-metal construction, except for fabric-covered control surfaces, the ANT-42 had a retractable tail-wheel landing gear with only the main units retracting. The intended powerplant was four wing-mounted engines with a central ATsN supercharger installation in the fuselage, but when the ANT-42 prototype made its maiden flight, with test pilot Mikhail Gromov at the controls, the proposed supercharger installation was not yet available and the machine was consequently powered by four 1,100-horsepower Klimov M-100 V-12 piston engines.

ww2dbaseAlthough the prototype ANT-42 was damaged during a heavy landing official testing was completed during 1937, following which an ATsN supercharger driven by a single M-100 engine became available. However, the arrest of Vladimir Petlyakov and much of his design team during the Great Purge of 1937 disrupted the development programme, and the second prototype ANT-42 would not make its maiden flight until 26 July 1938. This second aircraft, with accommodation for a crew of 11, contained many improvements including an ATsN-2 supercharger driven by the M-100A engine and a complete armament.

ww2dbaseJoseph Stalin's micro-management of this prestige project did not help matters. Although factories were ordered to begin tooling up as early as 1936, series production, authorised in April 1937, did not commence until 1939 with, initially, five pre-series TB-7s which differed from the ANT-42s in having Mikulin ANT-35 engines and the fuselage supercharger installation deleted. Even then, manufacture was plagued by a dire shortage of suitable engines so that deliveries to VVS squadrons could not commence until May 1940.

ww2dbasePerformance with the AM-35 powerplant was disappointing, leading to the evaluation of several alternative engines, until, in October 1940, the 1,400-horsepower Charomskiy ACh-40 V-12 turbocharged diesel was selected to be the standard powerplant. This engine unfortunately proved unreliable at high altitude resulting in the continued use of 1,350-hp AM35A engines until the bombers could be re-equipped with the improved 1,500-horsepower ACh-30B diesel.

ww2dbaseSome seventy-nine production machines had been completed by October 1942 (about 48 re-engined with the 1700-hp Shvetsov ASh-82FN 14 cylinder air-cooled radial engines). Few wartime bombers had a heavier defensive armament which consisted of a 7.62mm ShKAS machine-guns (later replaced by 20mm ShVAK cannon) in the dorsal and tail positions; a nose turret with a single (later twin) ShKAS machine-gun; and a single machine-gun position in the rear of each inboard engine nacelle accessible via a wing crawl-way. The standard bombload was six 100-kilogram or four 250-kilogram bombs, but over suitable short distances a maximum of 4,000-kilogram of bombs could be carried. Unfortunately the defensive effectiveness was somewhat limited by the Soviet inability to produce a reliable power operated turret - the traverse and elevation rates of manually operated turrets being too slow to be really effective.

ww2dbaseAt the start of Operation Barbarossa, the German invasion of the Soviet Union in June 1941, only the 2nd Squadron of the 14th Heavy Bomber Regiment (Tyazholy Bombardirovochnyy Avia Polk-TBAP), based at Boryspil was equipped with Pe-8s, but was not ready for combat. By that time the designation TB-7 had been dropped in favour of Pe-8. Two of the Squadron's nine available Pe-8s were destroyed by German air strikes shortly after the war began, forcing the Pe-8s to be withdrawn out of reach of German bombers to Kazan in Tatar ASSR. On the night of 10/11 August 1941, 18 of these aircraft made an attack on Berlin, but with one crashing on take-off from engine failure and eight others making forced landings for the same reason, it was finally decided to discontinue the use of diesel engines. All surviving Pe-8s were consequently re-engined with AM-35As by the end of 1941 and from late 1942 new machines were fitted with the 1,850-horsepower Shvetsov ASh-82 radial engine.

ww2dbaseA significant number of Pe-8s were lost to Luftwaffe night fighters and flak, but production just about kept pace with losses. One Pe-8 with AM-35A engines made a remarkable staged flight carrying Soviet Foreign Minister Molotov and his delegation from Moscow to Washington and back during the period 19 May to 13 June 1942. Surviving aircraft were used extensively during 1942-43 for close support bombing and, from February 1943, some were modified to deliver the heavy 5,000-kilogram FAB-5000NG general-purpose bomb on point attacks against special targets. In total 93 Pe-8s would be manufactured before production finally ended in 1944. About thirty remained at the end of the war. These were subsequently used for a variety of purposes, including employment as engine test-beds, and in 1952 two demilitarised Aeroflot machines played a key role in establishing an Arctic station before returning the expedition to Moscow in a non-stop flight of 3,107 miles.

Pe-8 Timeline

SPECIFICATIONS

Pe-8/AM35A

Machinery	Four Mikulin AM35A liquid-cooled V-12 engines rated at 1,340hp each
Armament	2x20mm lightweight ShVAK cannon in dorsal and tail turrets; 2x12.7mm Berezin UBT heavy machine-guns in engine nacelles; 2x7.62mm ShKAS machine guns in nose turret; up to 5,000kg of bombs
Crew	9
Span	39.13 m
Length	23.20 m
Height	6.20 m
Wing Area	188.66 m²
Weight, Empty	18,571 kg
Weight, Loaded	27,000 kg
Speed, Maximum	443 km/h
Rate of Climb	5.90 m/s
Service Ceiling	9,300 m
Range, Maximum	3,700 km

Photographs

Visitor Submitted Comments

Show older comments