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Designed by Boris G. Shpital'nyj. Information about this gun is scarce and not wholly consistent. It was (probably) a modified anti-aircraft gun. At Shavrov can be found, that a 37mm Shpital'nyj cannon was tried on N.N.Polikarpov's VIT-1 and VIT-2 anti-tank assaulter in 1937/ 1938, but the exact type is not stated.
In July 1941 People's Commissar of Weapons Dmitrij Ustinov had signed an order authorizing the construction of a batch of Sh-37 cannon for operational trials. They were intended for use on LaGG-3 fighters and 20 of those planes were tested in combat with relative success.
ShK-37 cannon is mentioned in connection with Polikarpov's ITP fighter prototype. In the Polikarpov's design big gun comfortably fitted between the engine cylinders and fired through propeller hub. Nonetheless, 'Fighter career' of the Sh-37 was also short: after factory trials of the ITP (M-1) its engine was replaced by other type, and hub-firing Sh-37 did not reappear on the following M-2 modification.
The weapon was also experimentally fitted to Il-2 attack aircraft. Evaluations showed that this gun proved a high kill probability against lightly armored targets at a range of up to 300-400m. But wing-mount gun of Il-2 with its large clip had to be installed in large under-wing fairing. As a result, large recoil momentum did not allow pilot to keep sustained aiming. The gun also proved itself to be relatively unreliable and was thus soon replaced by the NS-37.