Soviet tank engineering gained considerable momentum in the decade leading up to the fighting of World War 2 (1939-1945). Gone were the days of relying on foreign developments from the West and, in their place, emerged all-new indigenous offerings - some successful, some not. In the period immediately preceding the fighting of the Second World War, there emerged a new requirement for a heavy tank type to the Soviet ground assaults. This gave rise to two competing prototypes known as "SMK" and "T-100" - each following a very similar design approach involving multiple turrets housing capable armor-defeating weaponry.
Both designs ultimately failed in their attempts to succeed the clumsy, limited T-35 multi-turret heavy tank of 1935. The drive to field its successor stemmed from Soviet experience in the Spanish Civil War (1936-1939) which found the T-35 too lightly armored to be of value against more modern weapons.
For a period in tank warfare history, the "multi-turret" tank was the way to go, offering considerably more inherent firepower and armor protection that what could be had with conventionally-minded, single-turret designs. Of course this led to overweight, cumbersome machines that held little value on the mobile battlefields of the 1930s-1940s. As such, many languished as showpieces and propaganda products for their time in the limelight. Few ever saw direct, meaningful combat.
The SMK, the focus of this article, carried the initials of assassinated Communist party member Sergei Mironovich Kirov (1886-1934). Its multi-turret approach involved a primary turret seated over midships fitting a short-barreled 76.2mm L-11 main gun. A smaller, forward turret fitted a still-potent, long-barreled 45mm Model 1932 anti-tank gun and anti-infantry measures amounted to 3 x 7.62mm machine guns for defense. This gave the tank, at least on paper, a very wide field-of-fire from all of its gun positions - a quality akin to warships of the time. The extra turret, and all that accompanies it, of course added weight, length and a general awkwardness to the design as a whole and the initial design approach to feature no fewer than THREE primary turrets involving 1 x 76.2mm and 2 x 45mm guns - a design requirement ultimately dropped. Armor protection reached between 20mm and 60mm across the various facings - the vehicle was required to withstand hits from a 45mm anti-tank gun at short-to-medium ranges and a 75mm gun at medium-to-long ranges (out to 1,300 yards).
Internally, the vehicle would be crewed by no fewer than seven men - a quality reminiscent of the "land ships" of World War 1 seen decades earlier. Power was from a single GAM-34BT 12-cylinder gasoline-fueled unit outputting 850 horsepower and driving a traditional track-and-wheel arrangement involving a drive sprocket, track idler, and up to four or five track-return rollers. The engine was a modified version of a Mikulin aero-engine, such was the power required to move the beast. The 55 ton vehicle (the design range was between 50 and 60 tons) could hope to make about 22 miles per hour on prepared roads and reach out to 140 miles. A torsion bar suspension system attempted to provide some cross-country mobility and ride comfort - the original approach was to feature a spring suspension arrangement but this requirement was changed for the better.
Design of the SMK, begun in the spring of 1938, was through an engineering team based at the Kirovski Works Plant No.100 of Leningrad and two pilot vehicles were contracted for. The vehicle was unveiled for the first time in May of 1938 and it was at this time that the third turret requirement was dropped (a move thought championed by Stalin himself). The SMK proved ready before the end of April 1939 and was evaluated throughout the year - ultimately pressed into direct combat service during the "Winter War" (November 1939 - March 1940) against neighboring Finland. However, this is where the story of the SMK came to an end for it cross over a Finnish land mine on December 19th, 1939 which disabled its drive. The crew was forced to abandon the experimental vehicle and it laid in such a state until March of 1940 before being recovered by the Soviets. Some six T-28 tanks were needed to dislodge the steel monster and, once rescued, it was not rebuilt. Its hulk was scrapped sometime in the 1950s bringing about its official end.
Even while the SMK was being developed, the Kirov team was also drawing up plans for a single-turret heavy tank designated with the initials of "KV". This gained approval from Stalin himself and was favored through its combination of firepower, protection, and economics and went on to become the successful line of KV-1 tanks featured in the fighting of World War 2. In fact, the KV competed against both the SMK and T-100 offerings and won out over both.