The M-class submarines, also Malyutka class, were a class of small, single-, or 1½-hulled submarines built in the Soviet Union and used during World War II. The submarines were built in sections so they could easily be transported by rail. The production was centered in the Gorky Shipyard on the Volga River, after which the sections were transported by railway to Leningrad for assembly and fitting out. This was the first use of welding on Soviet submarines.
History
1930s to 1940s
Submarines of this class were in four series: VI, VI-bis, XII, XV. The number of VI and VI-bis series boats were almost equal. Series XII was a re-developed project with equivalent tactical characteristics. The first series were powered by one diesel engine and one electric motor. Series XV had developed separately with improved characteristics, including the main ballast in light hull and two shafts. These vessels were mainly used by the Black Sea Fleet and the Baltic Fleet. Although the design was satisfactory, only limited results were obtained and losses were heavy with 33 submarines sunk between 1941 and 1945. Seven submarines were lost in the Black Sea, four depth-charged and sunk by Romanian warships and three were sunk in minefields laid by the Romanian minelayers, Dacia and Regele Carol I. By 1945, some 111 M-class submarines had been completed, with another 30 XV-series completed between 1945 and 1947.
Cold War
Two submarines of the early series of this class, along with two s, and two s were sold to the People's Republic of China in June 1954 as the foundation of the People's Liberation Army Navy Submarine Force. Both the M- and S-class submarines were sold to China, and two more M-XV series of this class were sold to China a few years later. Those purchased by China were renamed, but the two leased Shchuka-class submarines were not. The four M-class submarines bought by China were renamed National Defense # 21, 22, 23 and 24 respectively.
Modern times
An M-class submarine was discovered near Tallinn in May 2012. The submarine is located in the Tallinn Bay between the islands of Aegna and Naissaar, at an approximate depth of. It is believed to be M-216, which was intentionally sunk in the area in 1962 for training purposes. Divers have confirmed that many components, including the periscope, are missing. It is also believed that the training exercise may have been ordered as a result of several deadly submarine accidents in the 1950s. One such accident happened near Paldiski, where the entire crew died during a failed rescue operation. Another M-class submarine was found in July 2015 by divers from Aquarius Dive Center Constanta, in front of Costinesti, at an approximate depth of. It is believed to be either M-34 or M-58, both being lost to Romanian minefields. The submarine is buried in the sand up to the deck level, and also completely filled with sand, making any further identification almost impossible. The upper part of the hull shows a pretty high level of damage - many ribs are exposed. The aft hatch was partially opened. The hull is in one piece, conning tower and deck gun intact.
Versions
;Series VI: 30 submarines constructed between 1932 and 1934
M-1
M-2
M-3
M-4
M-5
M-6
M-7
M-8
M-9
M-10
M-11
M-12
M-13
M-14
M-15
M-16
M-17
M-18
M-19
M-20
M-21
M-22
M-23
M-24
M-25
M-26
M-27
M-28
M-51
M-52
;Series VI-bis: 19 submarines built in four sections between 1934 and 1936) were 37.5 m long and displaced 202 tons submerged.
M-53
M-54
M-55
M-56
M-71
M-72
M-73
M-74
M-75
M-76
M-77
M-78
M-79
M-80
M-81
M-82
M-83
M-84
M-85
M-86
;Series XII: 45 submarines built in six sections between 1936 and 1941 were 44.5 m long, and displaced 258 tons submerged.
M-30
M-31
M-32
M-33
M-34
M-35
M-36
M-57
M-58
M-59
M-60
M-62
M-63
M-90
M-92
M-94
M-95
M-96
M-97
M-98
M-99
M-102
M-103
M-104
M-105
M-106
M-107
M-108
M-111
M-112
M-113
M-114
M-115
M-116
M-117
M-118
M-119
M-120
M-121
M-122
M-171
M-172
M-173
M-174
M-176
M-175
;Series XV: 4 submarines built in seven sections during World War II while other 11 built after it, until 1953 were 53.0 m long, and displaced 420 tons submerged.
M-200
M-201
M-202
M-203
Completed after World War II:
M-204
M-205
M-206
M-214
M-215
M-216
M-217
M-218
M-219
M-234
M-235
Both series VI and VI-bis were constructed by A. N. Asafov. Series XII was made by P. I. Serdyuk and series XV was created by F. F. Polushkin.