The German half-track armored personnel carrier Sonderkraftfahrzeug 251 (abbreviated SdKfz 251), better known in our country by the name of the manufacturer's company "Hanomag", became one of the symbols of World War II and was second only to the American M3 armored personnel carrier in terms of the number of copies produced. In total, from June 1939 to March 1945, more than 15.5 thousand of these combat vehicles of various modifications were produced. The armored personnel carrier turned out to be successful and did not lose its relevance even after the end of the Second World War, Czech designers and the military drew attention to it, who in the late 1950s developed and adopted an armored personnel carrier, at first glance at which it was clear which vehicle inspired its creators … We are talking about the Tatra OT-810 semi-tracked armored personnel carrier.
OT-810 can be called a make-up "Hanomag" in every sense of the word. This comparison not only emphasizes the general external similarity of the two combat vehicles, but also the successful film career of the Czechoslovak armored personnel carrier. After the war, especially after the withdrawal from service of the Czechoslovak army, the Tatra OT-810 armored personnel carriers very often appeared in war films because of their external resemblance to the Wehrmacht armored personnel carrier during the Second World War. The combat vehicle, already removed from service, is successfully filmed in films today, and is also actively used by reenactors around the world. The last film in which the Tatra OT-810 armored personnel carriers were shot is the film "Ilyinsky Frontier", the filming of which was completed in the Moscow region in November 2018. The world premiere of this film is scheduled for May 2020 and will be timed to coincide with the 75th anniversary of Victory in the Great Patriotic War.
After the end of World War II, Czechoslovakia was again restored as an independent state. Almost immediately the question of how to arm the country's army was raised. For the first time, the weapons and arsenal of the German army became a huge help. The Czechoslovak army received medium tanks Pz. IV, anti-tank self-propelled guns Hetzer, armored personnel carriers Sd.kfz. 251 and German semi-tracked tractors. Apart from tanks, all other equipment during the war years was produced at factories in Czechoslovakia, so there were simply no problems with the operation and repair of these combat vehicles. As the Soviet Union armed Czechoslovakia with military equipment of its own production, the tanks and self-propelled guns inherited from Nazi Germany were decommissioned from the army, and the cargo equipment was replaced with new Tatras, but an overlay came out with armored personnel carriers. The USSR produced an insufficient number of armored personnel carriers in order to freely send them to its allies. Only the BTR-40 and BTR-152 that appeared in the country were actively supplied to the Soviet Army, in the mid-1950s it was still far enough before the saturation of the Soviet units with such armored vehicles. This was the reason for the resumption of production in Czechoslovakia of a seriously modernized German half-track armored personnel carrier.
The Tatra OT-810 armored personnel carrier was a deeply modernized version of the German "Hanomag" and the world's only version of a half-track armored personnel carrier, which was produced after the end of World War II. The armored personnel carrier developed in the 1950s went into mass production in 1958 and was produced until 1963. During this time, in Czechoslovakia, they managed to release about 1800 combat vehicles - 1250 linear armored personnel carriers, the rest - special vehicles based on it. The production of the OT-810 armored personnel carrier was carried out at the Podpolyanske Stroyarne plant, located in the city of Detva (Slovakia).
During the war, the German half-tracked armored personnel carriers Sd. Kfz.251 for the needs of the Wehrmacht were produced, among other things, by the Czech company "Skoda" at the plant in Plzen. After the end of the war, a new armored vehicle was created at the Tatra plant in Kopřivnice for the needs of the Czechoslovak army. The combat vehicle, designated OT-810, externally retained its resemblance to its German progenitor, borrowing the original layout of the Sd. Kfz.251 / 1 Ausf. D. At the same time, the car was significantly modified in terms of some design solutions. The armored personnel carrier received a new air-cooled diesel engine manufactured by the Tatra company, a fully enclosed armored hull and an improved chassis.
It was the body that underwent significant modernization. The fighting compartment was expanded, loopholes were located in the sides and in the sash of the aft door for firing from personal small arms of the landing force, the shape of the stern was borrowed from the variant of the Sd. Kfz.251 / 1 Ausf. C. A full-fledged armored roof appeared on top, which protected the landing not only from bullets and shrapnel on the battlefield, but also from precipitation in the form of rain and snow. The roof of the hull was also equipped with a hatch that could be used by the commander of the combat vehicle. A turret was installed on it to accommodate a 7.62 mm machine gun, originally it was a vz. 52, but later it was replaced by another Czech machine gun vz. 59. The armor of the hull did not undergo major changes, the armor plates themselves were located at rational angles of inclination. The thickness of the frontal armor did not exceed 15 mm, along the sides of the hull - 8 mm. If the armored hull "Hanomaga" during the war years was assembled section by section using bolts, then the body of the Czechoslovakian armored personnel carrier OT-810 was all-welded.
The body of the new armored personnel carrier was welded from sheets of armored steel on a massive steel rectangular frame. The body layout remained unchanged and had a bonnet scheme. The engine was located in front. An 8-cylinder V-shaped air-cooled diesel engine manufactured by Tatra is located under the armored hood of the OT-810 armored personnel carrier. It was an engine of the Tatra T-928-3 model with a working volume of almost 10 liters. At 2000 rpm, this engine developed a maximum power of about 122 hp. On serial German "Ganomagh" gasoline engines "Maybach" were installed, the power of which did not exceed 100 hp. In addition to the engine on the OT-810, the shape of the muffler was also changed. The gas tank was located in the floor.
View of the control department OT-810
Immediately behind the hood was the control compartment with the seats of the commander of the combat vehicle and the driver. Behind them was the troop compartment, which was in no way separated from the control compartment, and could accommodate up to 10 fully equipped soldiers. The commander and the mechanic of the vehicle watched the road and the battlefield through observation windows located in the frontal sheet, as well as on the sides of the hull. These windows were covered with special armored covers with viewing slots, as well as bulletproof triplexes. Inside the hull, the paratroopers were located as follows: two paratroopers sat directly behind the mechvod and the commander, their places were located in the direction of the vehicle's movement, the remaining 8 people sat along the sides of the hull facing each other. The landing and disembarkation of the paratroopers was carried out either through the aft doors, or through flaps and a hatch in the roof of the hull.
The control of the OT-810 armored personnel carrier was carried out using the steering wheel, which has the same angle of inclination, which is unusual for a modern driver, as on the German analogue (the steering wheel is tilted down), as well as levers that controlled the onboard brakes and allowed the driver to steer the tracks, which significantly improved the maneuverability of the armored personnel carrier. The suspension of the Czechoslovakian armored personnel carrier had a half-track layout, as on the German counterpart. The front wheels had a spring suspension (one transverse spring was used) with hydraulic shock absorbers. The wheels had developed lugs and were tubeless, filled with foam and were resistant to bullet hits. The rear propeller was tracked and retained the staggered arrangement of the road wheels. This arrangement of the rollers increased the survivability of the machine and the smoothness of the ride, but seriously impaired the maintainability, especially in the field. The outer row consisted of three rollers, the inner one of four rollers, and the middle row consisted of six rubberized road wheels of large diameter, front drive and rear idler wheels. The track rollers were stamped to make them easier to manufacture. The suspension of the tracked part is torsion bar. The tracks themselves were also changed, rubber pads were removed from them and the lugs were increased.
The Tatra OT-810 armored personnel carrier could be used to transport trailers weighing up to three tons. In addition, some of the armored personnel carriers were equipped with a system of protection against weapons of mass destruction, a special filtering unit - FVU - was installed on them. The presence of the FVU on board led to a decrease in the number of paratroopers, since a significant amount of space located on the starboard side of the troop compartment of the armored vehicle was spent to accommodate the elements of the filter ventilation unit.
In this form, the Czechoslovak armored personnel carriers were actively exploited until the mid-1960s, when they began to be replaced by new armored personnel carriers OT-62 and OT-64. Since the mid-1960s, OT-810 armored personnel carriers began to be transferred to auxiliary units or converted into anti-tank ones, armed with an 82-mm recoilless gun. Also, this model continued to be operated as a conventional tractor, including for various artillery systems. The OT-810 anti-tank formations remained in service until the mid-1980s. At the same time, in the 1980s, OT-810 began to be massively removed from service by the Czechoslovak army, and in 1995 the last surviving copies were removed from storage.
On the basis of the OT-810 armored personnel carrier, a kind of analogue of a tank destroyer was also created. This combat vehicle received the OT-810D index. The undercarriage did not undergo any changes, but the fighting compartment was changed, the roof disappeared. Thanks to this, it was possible to place a conning tower with armored shields, reclining to the sides, they protected the 82-mm M59A recoilless cannon. If necessary, the gun could be relatively easily removed from the armored vehicle and used as an ordinary towed artillery system. The vertical guidance angle of the gun ranged from -13 to +25 degrees. The crew of the OT-810D tank destroyer consisted of four people: a driver, commander, gunner and loader. At the same time, the height of the combat vehicle with the gun and wheelhouse increased to 2.5 meters.
Interestingly, the German half-tracked armored personnel carrier Sd. Kfz.251 gave life not only to the post-war Czechoslovakian armored personnel carrier. His distant ancestor was a Daimler half-track truck. The truck was specially manufactured in Germany for Portugal and equipped with rubber bands that connected the drive wheels to an additional pair of idler wheels. Such a simple track design allowed the car to confidently overcome areas of soft ground.
The performance characteristics of Tatra OT-810:
Overall dimensions: length - 5, 71 m, width - 2, 19 m, height - 2, 10 m.
Reservation - 8-15 mm.
Combat weight - about 9 tons.
The power plant is a TATRA T-928-3 8-cylinder air-cooled diesel engine with a power of 90 kW (122 hp).
The maximum speed is up to 60 km / h.
The power reserve is 600 km.
Capacity - 2 (crew) + 10 (landing).
Armament - 7, 62-mm machine gun vz. 59 or 82-mm recoilless gun M-59A.