Picture 1:
This is the second part of a two part series exploring the interior of the Soviet T-35 Heavy Tank. The main turret housed a KT-28 76.2mm cannon and a coaxial 7.62mm DT machine gun. The turret was rotated either manually by hand wheel and worm gear or by a three-speed electric drive. Elevation was by hand wheel only and the turret was mounted on a platform higher than the other four turrets to allow the 76mm gun to fire in any direction simultaneously with the other turreted weapons. The drawing shows the left (gunner's) side of the main turret including his gun control handles and both the PT-1 periscopic sight on the turret roof (connected by lever to the main gun mount) and a TOP telescopic sight in the gun mantlet. The commander also had a periscope in the roof on his side, the typical PTK, and there was a small roof ventilator fan included between the two periscopes. Early T-35A turrets provided only one rectangular hatch opening, centered in the roof just behind the rear of the gun breech. Later turrets included two roof hatches, the gunner's on the left being circular and sometimes seen with an anti-aircraft MG mount around it, and the rectangular commander's hatch placed on the right. The large turret bustle allowed mounting the large Soviet tank radio of the time, the 71-TK-1/3 with a rail antenna surrounding the main turret. The radio consisted of a transceiver, telephone and telegraph. It was a 80kg simplex AM unit which broadcast in the 4000-5625Mhz frequencies bands. For internal communications the tank was said to have been equipped with a SPU-7r interphone with hookups for 7 of the crew, including the commander, radio operator, driver and each turret gunner.

Picture 2:
The main turret DT machine gun was not coaxially mounted with the 76mm weapon, but was located far to the right of the gun in a separate ball mounting of the same type as in the small MG turrets. To the right of the MG in this drawing is the commander's side vision slit and block holder with a small firing port plug located beneath. Just behind the commander's large padded seat with its high seat back is the smaller combat seat for the radio operator which folds up against the turret floor support tube it is mounted on. At the rear of the turret ring is a similar folding seat for the loader/mechanic and on the left of the turret is the gunner's weapon controls and his seat with its tall back. An electric motor is mounted horizontally on the turret race, in front of the traverse hand wheel, and provides three-speed electric turret traverse. To the left of the gunner is his turret wall vision slit, again with triplex glass blocks and firing port below. The turret has a full suspended floor attached to the turret ring by four tubes and the floor has a large rear hatch for access to ammo rounds stored underneath. Under the gunner's and commander's seats are upright storage carrousels for six 76mm shells (tip up), and an additional ammo rack and for 12 rounds and a box holding MG ammo is located between the seats. Elevation for the 76mm gun is +25 to -5 degrees. Muzzle velocity for the big gun is 381mps, and the weapon can fire either shrapnel or HE-FRAG rounds.

Picture 3:
The turret basket and floor are simply made and contain no basket walls to restrict retrieving ammo from hull mounted racks on both sides of the vehicle. The floor is covered with textured black rubber mats and the 6-round vertical racks under the gunner's (left) and commander's (right) seats are seen here. Both of these seats were height adjustable, but the loader/mechanic's and radio operator's smaller folding seat bottoms are bolted directly to the floor supports and are not adjustable. The rack/bin under the gun has clips for six additional rounds on each side and room in the top for MG ammo drums. Because the turret sits proud of the hull on a higher level, the turret floor to ceiling distance is considerable and allows the crew to easily stand up inside. Keep in mind that the maximum height for Soviet tankers allowed at this time was only 5ft 3in (1.6m). With a 2 meter distance from the ground to the top of the fenders, you can imagine the problems these soldiers had with just mounting the AFV!

Picture 4:
This is the short barreled KT-28 cannon (KT= Kirov Tank) breech inside the Kubinka vehicle. At the left side of the mantlet (near the cannon barrel) is the mount for the missing telescopic sight, and below is the manual elevation hand wheel connected, via worm gear, to the gun mount directly in front of us. At the far left is the white horizontally mounted traverse electric motor and just visible on the side of the gear casing is the control lever handle for the motor. I do not see the manual traverse hand wheel in this photo, I suspect it is a bit further off to the left. I believe the gun breech is an interrupted screw type and is hinged on the right. It should unlatch and swing open with a hard pull from the vertical wooden handle, the breech first rotating 45 degrees to free itself, and then opening to its full width to allow a round to be shoved home. The breech is then closed by pushing the handle around and forward again to lock it. A large recoil guard with numerous litening holes is positioned between the gunner and breech as the gunner sits very close to the weapon while in action. Just visible to the left of the gun is the alignment rod that attaches from the gun mount to the over-head periscopic sight, which is also not mounted in this museum specimen. Off to the far right is part of the ball mount for the DT MG. Although this rendition of the photo is in black and white, I have been told by those who have seen the inside of the turret that the walls, roof and floor (under the black rubber mats) are painted in their original white and the cannon and mount are the typical yellow/green color of many Soviet tank weapons.

Picture 5:
Here is the breech end of a Russian Model 1927 76mm Regimental Cannon with the same breech and breech ring as our KT gun, but in much better photographic condition. This weapon has an interesting history. Originally, the gun was designed by W.N. Sidorenko and designated Model 02/30 by the Tsarist Army. It was built in two lengths, the original 30 calibers and a later 40 calibers, which only marginally improved its ballistic capabilities. Surprisingly, the Model 02/30, in its original form, was still in use by North Vietnam in 1974. When the Model 1927 Regimental Cannon was later rebuilt, just before WWII (with a better carriage), the gun received the designation Model 1927/39 76mm Regimental Cannon. According to some sources it remained in survice in front line use by Soviet Rifle and Cavalry Divisions until 1943. It's heavy weight caused considerable towing problems and the gun was finally replaced in '43 by another 76mm gun (OB-25). Here we see that the breech is indeed an interrupted screw type with the striker mechanism mounted to the rear of the breech and the laynard attachment leading off to the left of the weapon. In the KT 28 application, the striker is linked via a long rod to a foot pedal in front of the gunner and the weapon is fired in this manner. The main differences between the KT version of the weapon and the Regimental Cannon is increased recoil cylinder fluid and pressure in the KT to shorten the gun's recoil run-out and improved and strengthened slide rails to better support the weapon during the shortened recoil. Notice the small twin recoil cylinder caps below the breech in the run-out tray and compare this photo to the previous picture of our KT-28 inside the T-35.

Picture 6:
The PT series of periscopes used in the T-35 were generally used in may Soviet tanks during the 1938-1942 period. This photo from the US Archives is a crop of a KV tank turret interior, showing the same PT periscope used in the T-35, mounted here also on the gunner's side of the turret. The panoramic periscope consisted of a Harting Dove prism, placed between two telescopic systems. Each telescopic system was adjustable independently of the other and contained a reticle in the focal plane of the objective. In the focal plane of the eyepiece there are two cross wires which can be moved independently of each other and form the aiming cross hairs of the system, the aiming of the cross hairs being controlled by the knobs near the eyepiece. In this photo you can see the large black periscope mount in the turret roof and the cylindrical shape of the periscope hanging down. The gray cylinder ends in a black box that houses the eyepiece and a large dial and handle on the right moves the line of sight vertically. In this case the dial handle is connected to the gun mount, as would also be true for the T-35. This was the mechanism that kept the sight lined up with the gun tube for all elevations. The periscope was lighted and one of the wires from the left is power to light the bulb inside the unit. The PT series of periscopes were also used in the commander's position to the right of the main weapon, with the only difference being the lack of a gun mount link on the dial handle replaced with a simple hand knob for the commander's use.

Picture 7:
This is another illustration of a PT periscopic sight, in this case the PTK version. Once again you can see the primary cylindrical body, ending in the black box containing the eyepiece. As with the previous picture, the monocular eyepiece has a padded black rubber eye ring and is covered above with a large padded face/brow pad. The metallic control knob that moves the horizontal cross hair is seen to the left of the body tube while the vertical cross hair control knob is below and behind the scope and seen only on the rear view image at the left. The vertical adjustment dial handle is clearly seen on the right side of the unit, this time ending in the hand knob, as it would for the commander's unit in our T-35 (and in the KV). The total field of view for the PTK is a bit more than 25 degrees, but the view clarity drops off dramatically to each side of center, leaving only around 12 degrees of clear useable view in the scope. There are also occasional small bubbles in the glass that further degrade the image clarity. Magnification is 2x, with the total optical length being a bit over 28 inches from eyepiece to top prism. Early T-35 vehicles are often seen with no protection for the top prism, while later vehicles were provided with a protective cylinder around this exposed portion.

Picture 8:
Beginning in 1937 most T-35A main turrets had a P-40 hp ring mounted around the gunner's circular hatch for attaching a DT machine gun for anti-aircraft use. In this very interesting photo of a late T-28 or T-35 turret roof we see a posed crewman using the P-40 mount which rotated 360 degrees around his hatch opening. The elevation mechanism was a simple geared plate with elevation possible by use of a second gear attached to the MG with a rotating wooden crank handle for the gunner. The gun mount attached at the front edge of the DT MG receiver with a thumbscrew (on the far side of the mount). The exposed hand crank mechanism was crude, but effective, but the exposed gearing must have caused serious injuries to careless fingers. Notice the deeper magazine drum used with the DT version of the DP machine gun. Also notice that the typical turret rail antenna has probably been replaced with an odd rod type, sitting in the antenna pot mount, on the right of the turret roof (far left in this photo). I have never seen a T-35 antenna of this type, although some T-28 vehicles seem to have used these. Also of interest here is the use of the later, more economical, black canvas Soviet tanker's helmet, generally not thought to have replaced the brown leather type until around 1941, which dates this Soviet photo to that time period. The crewman also seems to be wearing the black or dark blue overalls used during the early years of WWII. Usually, although not always, khaki overalls replaced the darker types by around 1942. Also notice the unprotected upper prism of the gunner's PT periscope and the dark color of the inside of the circular hatch.

Picture 9:
The engine was a four cycle, 12-cylinder, V-type M-17 gasoline aircraft engine. Its maximum horse power was around 500 at 1450rpm for the early vehicles and 580hp after the 1936/37 rebuild for the later vehicles. Three fuel tanks were carried- two of 320 liters to either side of the engine and one of 270 liters behind the rear MG turret. Twin KD-1 type carburetors supplied the air/fuel mixture along the top of the engine and the power unit was water cooled by twin radiators mounted to each side of the engine compartment. The transmission compartment was separated from the engine at the rear of the tank and contained the gear box, with 4 forward and 1 reverse speeds, and a power take-off for the large deck mounted fan to cool the radiators and engine compartment. This drawing helps locate most of the main components of the engine compartment. The V-12 is seen at our end, flanked by the slanting radiators. Cooling air is drawn into the compartment by the fan at the rear and enters under two armored shields along the side of the engine deck. It is drawn through the radiators to the engine and along its length to the fan PTO and then out the top of the rear of the engine deck via the fan. From the gearbox at the rear of the AFV projected two shafts running to the twin multidisk steering clutches and ribbon brakes, which were then attached to the final drives and rear drive sprockets. The tank was very long for its width, and turning this tank was a slow and difficult proposition for the driver. The engine compartment also had a fixed fire extinguishing system consisting of carbon tetrachloride in cylinders, fired by the driver/mechanic. Another extinguisher cylinder, this one portable, was kept up forward near the driver's seat.

Picture 10:
As a design project, the T-35 plan came along at a time when many of the major military powers were experimenting with large multi-turret ideas. The British had their similar 5 turreted Vickers Independent, the French their Char 2C, and the Germans their 3 turreted Neubaufahrzeuge. However, it would take a long stretch of anyone's imagination to say the T-35 was a successful design other than as a "learning experience". The engine and transmission were constantly a problem, being overtaxed by both the weight and length of the machine. The final drives and cooling system often failed and if a T-35 managed to drive 250 miles before a major component failure it was considered a "miracle" by the crew mechanics. But, as far as the crew was concerned, the worst design flaw was the placement of all the vehicle hatches on the top of the tall AFV, guaranteeing that any escaping crew would be visible and easily machine gunned as they attempted to flee a damaged and disabled T-35. This war time photo from the Bundesarchiv illustrates this fact well, as each of the crew hatches on the top surfaces of the tank are open. The driver's split hatch has been allowed to open only because the MG turret behind it has been thoughtfully rotated to the left. The MG turret hatch is open, showing the two release handles on either side of the door, and the front medium turret hatch is also flung open wide. Up above, the main turret hatches are opened- the round gunner's hatch is clearly visible standing up straight while the rectangular commander's hatch is barely seen as it lays almost flat on the turret roof. Behind the main turret, the second medium turret has also been opened and even the large engine compartment access hatch on the rear deck has been lifted to expose its contents. Notice that the hatch interiors are painted the primary exterior paint color, probably dark Soviet green here, even though the interior MG turret wall is very light and probably white. There is much detail visible here for study, including the fact that this AFV was at one time fitted with the rail radio antenna that circled the turret- the wire pot entrance into the turret roof and the turret side supports are visible- but the antenna itself is now missing. All the DT machine guns are also gone. These were usually removed and burried by the crew, along with the ammo, when the tanks were disabled, to prevent them from falling into enemy hands.

I am in debt to a number of people for their assistance with this page, including Mike McSwiney of Technical Virtue and Steven "Cookie" Sewell for reference material and Russian translations, as well as M-K Magazine for some of the illustrations. If you have additional information or illustrations you would like to add to this page we would all be interested to hear from you.

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