Shpitalny Sh-37 | |
---|---|
Type | |
Place of origin | Soviet Union |
Service history | |
Used by | Soviet Union |
Wars | World War II |
Production history | |
Designer | Boris Shpitalniy |
Designed | 1940-1941 |
Manufacturer | Factory no. 74 |
Produced | 1941-1942 |
No. built | ~240 |
Specifications | |
Cartridge | 37×198mm |
Barrels | 1 |
Action | gas operated |
Rate of fire | 170-185 rpm |
Muzzle velocity | 900 m/s |
Feed system | magazine |
The Shpitalny Sh-37 (Russian: Шпитальный - Ш-37) was the first indigenous Soviet 37 mm (1.5 in) aircraft cannon, designed by Boris Shpitalniy at OKB-15. The gun saw limited production and was installed in few aircraft before being replaced by the competing Nudelman-Suranov NS-37 designed at OKB-16. It was installed on a military-trial basis on two short series of aircraft. Installed to fire through the hollow, gear-driven propeller shaft and fastened to the engine block of the Yak-7-37 it was known as MPSh-37, where "MP" stands for "motornaya pushka", similar to the German Motorkanone term for the same mount type. As installed in the underwing gun pods of the Il-2 it was known as ShFK-37 (Russian: ШФК-37 - Шпитальный фюзеляжно-крыльевая калибра 37 мм).
In 1940, after the Red Army accepted for service the 61-K 37 mm anti-aircraft gun, the VVS leadership decided to equip some fighters and a part of the upcoming production series of the Ilyushin Il-2 ground attack aircraft with a 37 mm autocannon capable of firing the same shell. Shpitalniy designed a gun that was gas operated and magazine fed, which however used a less powerful cartridge than the 61-K gun.
By early 1941, a prototype Sh-37 was flight tested on a LaGG-3 fighter. As installed in the LaGG-3, the gun together with its magazine weighed 208.4 kg. In this test it achieved a rate of fire of 184 rounds per minute.
At the end of June 1941, it was decided that within 45 days 40 more Sh-37 were to be produced for military trials. These were manufactured as planned by factory 74. In 1942, the same factory produced a further 196 Sh-37 guns.
The first LaGG-3 aircraft equipped with the Sh-37 gun were delivered to the 42nd IAP in the beginning of 1942. In August 1942, a small series of 22 Yak-7-37, equipped with the same gun, passed military trials with the same 42nd IAP, led by Boris Shinkarenko. The Sh-37 was powerful enough to down an enemy fighter with a single hit. Its shell could punch a hole with an area of over 1 square metre (11 sq ft). The MPSh-37 was supplied with 20 rounds of ammunition in this aircraft. The Yak-7-37 was additionally armed with two UBS 12.7 mm machine guns, with 450 rounds total ammunition. The weight of fire of the Yak-7-37 was 4.15 kg/s (9.15 lb/s). The length of the Sh-37 gun necessitated moving the cockpit some 40 cm rearwards, and the weight of the Yak-7-37 increased by some 200 kg compared to its proximate predecessor, the Yak-7B.