Key point: The T-35 was overly complicated and its crew were at risk from the thinner armor. Here is how the T-35 fairly poorly on the battlefield.
Recently, a Russian military museum in Sverdlovsk unveiled a moving replica T-35 tank, recreating one of the largest tanks ever to see combat, though only very briefly. Indeed, a few dozen T-35s charged straight into the largest tank battle in history—and none came back. Overtaxed transmission and faulty clutches proved a greater nemesis than armor-piercing shells.
Soviet Land Ironclad
In his 1903 short story, science fiction writer H.G. Wells imagined that the wars of the future would be won by towering ‘Land Ironclads’—a term referencing nineteenth-century armored warships. Just thirteen years, the United Kingdom deployed the first Mark I tanks to battle, each bristling with multiple cannons and machineguns operated by a crew of eight.
By the end of World War I, however, it grew apparent that lighter, faster single-turret tanks with small crews were more practical. Still, armies continued to conceive of hulking multi-turret ‘land battleships’ such as the French Char 2C and German Neubaufahrzheug.
In 1930, the Red Army sketched plans for heavy ‘breakthrough tanks’ intended to penetrate fortified defensive lines, using their multiple gun turrets to blast foes from all sides. However, the Soviet Union lacked necessary design expertise, so it brought in German scientist Edward Grotte to brings its engineers up to speed. It is possible Soviet engineers were also inspired by the Vickers A1E1 Independent, a hulking British tank prototype with five turrets.
Recommended: The Fatal Flaw That Could Take Down an F-22 or F-35.
Though Grotte’s TG-5 tank design proved unworkable, two T-35 prototypes were eventually built in 1932, the second simplified to make it more affordable. The first T-35A finally entered production at the Kharkov Locomotive Factory in Ukraine on August 1933.
In a fascinating interview shortly before his death, T-35 driver Smolyakov Ivan Erastovich, (“the best tractor driver in his village”) recalled his first encounter with the vehicle:
Five turrets, barrels sticking out in different directions. You needed a special ladder to climb up it. And it was, well, so huge that word cannot express it. Scary even. And the crew—a whole soccer team of ten!
The behemoth’s nearly ten-meter long hull mounted three cannon and two machinegun turrets, stacked two stories high. The main turret peaked 3.4 meters high and mounted a 76mm KT-28 low-velocity gun with ninety-six rounds of ammunition, as well as a DT machinegun in a ball mount and a ‘clothes-line’ style radio antenna. A machinegunner, a tank commander/gunner, and radio operator/loader were crammed inside. Later T-35s sometimes mounted one or two more machineguns on the turret: one on an anti-aircraft mount, the other facing the rear.
The two secondary cannon turrets mounted 45mm high-velocity cannons with better armor penetration (and over 220 shells each), and another DT machine gun each. These two-man turrets were situated diagonally from each other, one facing to the front and right of the vehicle, the other situated behind the main turret covering the arc to the rear and left.
Finally, there were two one-man machinegun turrets covering front-left and rear-right arcs. A driver was also seated in the main hull in a position that afforded him very little visibility.
The crew of ten (or twelve, if you counted dismounted engineering personnel) communicated through six intercoms—but practically speaking the tank commander had limited visibility and little ability to coordinate such a large crew. Remember, he also had to aim and fire the main gun! Worse, the turrets were physically isolated from each other, though there were corridors connecting the secondary gun turrets on each side. Several of the exit hatches were located adjacent to gun turrets, meaning certain crew had no way of getting out if that turret was stuck in the wrong position.
One expects a ‘heavy tank’ to be heavily armored—but the T-35s long hull made it prohibitively weighty to install thick armor plates. Thus, the T-35 had only mediocre armor protection of 30mm in the front, and 20mm of riveted and welded steel armor on the side, rear and turrets.
On May Day, 1934 the Red Army proudly paraded the land battleships through Moscow and the tank rapidly became a star of Soviet propaganda—appearing on posters even two years after the type had left service. But the Soviets quickly realized the T-35 had big problems.
Honestly, the T-35 was not a sweetheart. A very heavy tank, and complicated… It was difficult to control. It was necessary to be physically strong to drive it. There was a rule—after every 50 kilometer’s march, it was necessary to inspect it. Often something had broken. The transmission was disaster. We did not do any long road marches, we tried to preserve them.
Between 1934 and 1939, only fifty-nine production T-35s were built. The Red Army did not aim for larger scale production, as at 525,000 rubles each, a single T-35 could have paid to produce nine BT-5 light tanks. Instead, the Soviets combat tested two more multi-turret prototypes, the SMK and T-100, in Finland, before settling on the single-turret KV-1 heavy tank.
Still, virtually every aspect of the T-35’s design—from radios, to guns, to armor—was tweaked with each new factory batch. The Soviets learned from combat experience with lighter tanks in Spain and Mongolia that even light anti-tank guns would be able to pierce the T-35’s armor, so later models had the narrower frontal armor beefed up to 50–70mm. 10mm armored side skirts were also added to the lower hull. Around 1938, a final production run featured a new conical turret with 30mm of sloped armor.
However, heavier armor increased the weight from forty-nine to fifty-four tons—worsening the vehicle’s true Achilles’ heel: mobility. The T-35’s 500-horsepower M-17M petrol engine could theoretically boost the tank to eighteen miles-per-hour on road—but that dropped to only eight or fewer miles while going cross-country, and most of the Soviet Union still relied on dirt roads. The vehicle’s transmission, clutch and gearbox could barely tolerate the strain, and T-35s regularly broke down attempting to travel short distances.
The Soviets also designed two prototype self-propelled guns from the T-35 chassis. The Su-14-1 mounted a 152mm BR-2 gun above the hull, while the Su-14-2 had an even larger 203mm howitzer. Unlike most Soviet self-propelled guns of the era, these were designed to shoot at distant targets indirectly (ie, beyond visual range). The Soviets considered converting its T-35s to Su-14s in 1940, but instead elected to dispatch them to frontline units in Ukraine. The two Su-14s may have fired shells at advancing German troops during the defense of Moscow, but did not see further development.
The Land Battleships Roll to their Doom
Nazi Germany launched its invasion of the Soviet Union on June 22, 1941—and inflicted staggering losses on disorganized Soviet ground and air forces. However, Gen. Mikhail Kirponos deployed over 3,400 tanks in six Soviet mechanized corps during a counterattack aimed at the towns of Brody and Dubno. The resulting Battle of Brody was likely the largest tank battle in history.
At the time, forty-eight T-35 tanks were assigned to 67th and 68th Heavy Tank Regiments, part of the 34th Tank Division of the 8th Mechanized Corps in the area around Kharkov. (The remainder were awaiting repairs in workshops or deployed to military schools.) The T-35s began a chaotic week-long road march starting towards the frontline, while German warplanes subjected them to near constant bombardment.
Driver Erastovich’s account is typical of what befell the T-35s:
We were still 50 kilometers from Brody on the evening of June 27 when we received a new order - to turn to the south, to Zlochev, and from there to Tarnopol ... We had no idea what was going on, and we were not the only ones. Some many people were going this way in that on the road, everything was a mess.
Not far from Tarnopol, our friction clutch burned out. There was nothing to do, and we abandoned the tank. The machine guns were removed, as expected, as were the optics. So our giant did not reach the Germans.
Of the forty-eight T-35s, records show twenty-six suffered mechanical breakdowns on the road and were abandoned. Broken fan belts, friction clutches, malfunctioning reduction gears and gearbox failures were common culprits. At least eight more were ditched because routine repairs could not be performed. The T-35’s excessive weight contributed to four more losses: two literally fell through bridges, one taking its entire crew with it. Another two T-35As got bogged down in a swamp and had to be abandoned.
Not only did the Red Army lack adequate tank tractors, but the T-35 usually required two; in the chaotic circumstances of unfolding military catastrophe, the super-expensive tanks simply had to be left behind.