The SU-76 (Samokhodnaja Ustanovka 76) was a Soviet self-propelled gun used during World War II.
The SU-76 was based on a lengthened version of the T-70 tank chassis. Its simple construction made it the most-produced Soviet armoured vehicle of World War II, except for the T-34 tank.
Crews loved this vehicle for its simplicity, reliability, and ease of use, although it sometimes was nicknamed suka ('Bitch'), Suchka ('little bitch') or Golozhopiy Ferdinand ('naked-ass Ferdinand') for its relatively thin armour in the back. One famous crewman was Rem Nikolaevich Ulanov, who is a distinguished Great Patriotic War veteran. In his younger days he was a mechanic-driver and later a commander of an SU-76. He and some other soldiers called their SU-76 Columbina after female personage of Renaissance Italian Commedia dell'Arte.
The design work of SU-76 had begun in November 1942, when the State Defense Committee ordered the construction of infantry support self-propelled guns armed with the ZiS-3 76.2-mm gun and the M-30 122-mm howitzer. The base of a light tank T-70 was chosen for mounting the ZiS-3 gun, and it was lengthened, adding one road wheel per side, to facilitate better gun mounting.
In the rush for fast completion of the order a quite unreliable power plant was installed in the first mass production SU-76. It utilized two automobile engines (GAZ-202) in 'parallel' junction. Practically, each track had its own engine and it was quite difficult for the driver to control two engines simultaneously. Moreover, the strong vibrations lead to quick mechanical failure of the engine or transmission units. The vehicle was completely closed by armour. After producing 320 SU-76s, mass production was halted by authorities in order to fix the problems. Two chief designers of GAZ plant, N. A. Astrov and A. A. Lipgart, quickly changed the power plant to the reliable T-70 design. Also the roof of battle compartment was removed for better gun servicing. This modification, called SU-76M, was relaunched in mass production in early 1943. This pause was the cause for introducing SU-76i as a temporary replacement for SU-76. After the pause, GAZ and two factories in Kirov and Mytishchi produced 13932 SU-76M (the larger part of the order, over 9000 vehicles, was built by GAZ solely). Mass production of SU-76M ceased in the second half of 1945. Now the SU-76Ms (due to their vast number in comparison with original design SU-76) are often referred in texts, public radio and TV broadcasting as simply SU-76s with index 'M' omitted. The SU-76 was the base for first Soviet tracked armoured anti-aircraft vehicle ZSU-37. The mass production of ZSU-37 was continued after ceasing SU-76M production. The SU-76M was quickly withdrawn from Soviet Army service after the Second World War ended.
