So that the tracked armored combat vehicle does not waste its resource and does not spoil the road surface, it should be transported to the place of work using special vehicles. The transfer of armored vehicles along the roads is carried out using special road trains-tank transporters with semi-trailers of a special design. Perhaps one of the most interesting examples of this kind is the Belarusian road train MZKT-74135 + 99942 + 83721. This complex is capable of simultaneously transporting two tanks or three armored vehicles of lesser mass.
The history of the MZKT-74135 + 99942 + 83721 project began in the mid-nineties, when the Minsk Wheel Tractor Plant decided to find buyers in a new region for itself. The designers of the enterprise have begun to work out the appearance of promising tractors and other special equipment adapted to work in the difficult conditions of the Middle East. Based on the results of the research work, some interesting proposals were made regarding certain features of the technique.
The first version of the MZKT-74135 tractor with a French semitrailer
So, to work in hot climates, the power plant had to be equipped with cooling means of appropriate power. It was found that such units cannot be used on a cabover-less machine, traditional for MZKT. For this reason, for the first time in the history of the enterprise, it was decided to build a car with a pronounced hood that can accommodate all the necessary devices. Later, taking into account the wishes of the customer, other features of the appearance were determined.
The MZKT-74135 + 99942 + 83721 project in its present form was launched in 1998, when the Ministry of Defense of the United Arab Emirates announced a tender for the purchase of tanker road trains. The army wanted a complex consisting of a tractor and trailers capable of transporting the AMX-56 Leclerc main battle tank. An alternative payload was to be two BMP-3 infantry fighting vehicles. In addition, it was required to ensure the possibility of transporting crews of equipment. All this made special demands on the road train, but several leading companies in the automotive industry applied for participation in the program.
Soon after the launch of the competition, tests of the provided machines of several types began at the training grounds of the Middle East country. Together with the Belarusian enterprise MZKT, German, American, Czech, etc. took part in the competition. companies. An experienced MZKT-74135 tractor was sent to the UAE for comparative tests by the customer's forces. The Minsk plant had not had time to develop the required trailers by this time, which is why the tractor was tested together with the semitrailer of the French company LOHR.
The first tests were completed successfully. The MZKT-74135 tractor showed itself well and, in general, satisfied the potential customer. At the same time, the UAE military criticized the dimensions and characteristics of the presented French semi-trailer. Fortunately, by this time the development of our own products with the required characteristics had already started. As conceived by the designers of the Minsk plant, together with the new MZKT-74135 tractor, the MZKT-99942 semi-trailer and the MZKT-83721 trailer should be used. The use of two such devices at once made it possible not only to fulfill the customer's requirements for the number and weight of the transported armored vehicles, but also to surpass them.
In 2000, some of the best tank carriers underwent new tests in the UAE. This time, the Minsk road train was tested fully equipped and included a couple of new trailers. From the point of view of technical and operational characteristics, the Belarusian development, at least, was not inferior to competitors. At the same time, she had a special advantage in the form of the ability to transport two tanks or three less heavy armored vehicles at once. In addition, in the large cab of the tractor there were places for the crews of the transported equipment.
Based on the results of tests in 2000, the army of the United Arab Emirates decided to purchase the MZKT-74135 + 99942 + 83721 road trains. The contract for their supply was supposed to appear in the very near future, but the negotiations dragged on. The document was signed only in 2002. In accordance with it, in the near future the Minsk Wheel Tractor Plant was to build another prototype, modified in accordance with the wishes of the customer. After testing it, full-scale serial production could be launched. Taking into account the second prototype, the order provided for the construction of 40 road trains.
Updated road train MZKT-74135 + 99942
The updated and revised tractor with the old name MZKT-74135 was built and tested in 2004. In fact, a deep modernization was carried out with a complete alteration of the power unit, a change in the cab, etc. The main technical characteristics remained the same, but a number of parameters were significantly improved.
In both versions, the MZKT-74135 tractor is a four-axle all-wheel drive machine with a bonnet configuration, equipped with a fifth wheel coupling for interaction with a standard semitrailer. At the same time, there were noticeable external and internal differences. In particular, the contours and proportions of the body have changed. The cab was redesigned, which deprived the tractor of a slight resemblance to the previous MZKT vehicles.
The MZKT-74135 tractor is built according to the bonnet layout and has a large engine compartment. All units are mounted on a rectangular frame assembled from Z-shaped profiles. In the modern version of the project, the engine is covered by a hood with rounded contours. The front wall of the engine cover has a large radiator grill. Behind the engine compartment is the cockpit with a two-row arrangement of seats. Behind the cab, in an open area, it is planned to install a winch and a means of transporting a spare wheel. The rear of the chassis serves as the basis for the fifth wheel coupling.
In the first version of the project, the tractor was equipped with a German-made Deutz MWM TBD 234 diesel engine, which developed a power of 788 hp. Used hydromechanical transmission Alison M6600AR. As part of the modernization, the car was equipped with a Daimler Chrysler OM 444LA diesel engine with a power of 796 hp. The new engine is mated to an improved Alison M6610AR automatic transmission with six forward and two reverse gears. From the gearbox, the torque is transmitted to the transfer cases, which provide the drive of the central gearboxes with cross-axle differentials on each axle.
A pair of front axles of the tractor are equipped with an independent double wishbone torsion bar suspension. The rear axles have an independent double wishbone suspension with springs. Wheels with wide-profile tires Michelin 23, 5R25XLB TL 188E are used. The front two axles are steerable; there is a hydraulic booster in the steering system. The axles are mounted on the frame at different intervals. The distance between the first and second axles is set at 2, 2 m, the second gap - 2, 75 m. Between the third and fourth bridges, which take on the main load, only 1, 7 m.
The fifth wheel coupling of the tractor is located at a height of 2.05 m and is capable of accepting loads of up to 26 tons. The “saddle” is installed directly above the third axle of the chassis, which allows for optimal distribution of the load on the ground.
To work with various loads, the MZKT-74135 tractor is equipped with its own winch. The ITAG WPH-250-2 is equipped with a two-speed hydraulic drive. Delivery of ropes 100 m long is carried out from two drums. Traction force of 200 kN for each drum allows any equipment to be pulled onto the semitrailer.
The tractor is equipped with a fiberglass crew cabin with an increased number of passenger seats. Initially, the cab had the characteristic reverse tilting windshield, borrowed from existing special equipment, but then it was replaced by a pair of large glasses. There are two doors in the sides, opening in different directions. Access to the cab is facilitated by high ladders placed in the first inter-wheel space.
The large size of the cabin made it possible to install not only space for its own crew, but also seats for passengers - crews of the transported equipment. The seats can be converted into sleeping places if necessary. The tractor was originally equipped with an air conditioner, but the tests of 1998-2000 showed its insufficient power. The upgraded car received a more powerful climate system. At ambient temperatures up to + 55 ° C, no more than + 20 ° C is maintained in the cab.
The tractor has a length of 10, 51 m with a width of 3, 18 m and a height of 3, 95 m. The curb weight reaches 29, 9 tons. 12,450 tons of load, two rear ones - 15 tons each.
The second element of the unique road train is the MZKT-99942 semi-trailer. This product is built around a box-spar frame connected to a load-bearing deck. Also, the platform is equipped with side covers that cover additional equipment. The front part of the semitrailer platform is curved, which made it possible to increase the usable floor area and get space for additional cargo, while maintaining full compatibility with the fifth wheel of the tractor. There are six axles under the main platform, each with a pair of wheels. Hydraulically operated folding ladders are provided at the stern.
To increase its autonomy, the semitrailer is equipped with its own engine connected to hydraulic and pneumatic pumps. The hydraulics are responsible for moving the front legs of the semi-trailer and ladders. The pneumatic system controls the tire pressure. Control over the operation of the hydraulic and pneumatic systems is carried out from the console in the tractor cab or from a remote device.
The total length of the MZKT-99942 semi-trailer exceeds 18.5 m, the width is 3.65 m. The loading height is 1.5 m. The rear flat part of the cargo platform is 9.5 m long, the front inclined part is 5 m. The equipped product weighs 21 t The weight of the transported cargo is 70 tons, which corresponds to the carriage of one Leclerc tank or two BMP-3 vehicles. In this case, the main part of the load falls on the semi-trailer's own wheels, while only 26 tons are transferred to the tractor.
The last element of the tank carrier was the MZKT-83721 trailer. This product is a four-axle high-capacity bogie transported behind MZKT-99942 using a tow bar. This trailer has a loading platform with a length of just over 8 m and a pair of folding ramps at the stern. With its help, the road train can take on board an additional tank or combat vehicle.
The total length of the MZKT-83721 trailer, excluding the towing device, is 9.26 m, width - 3.65 m. The loading height has been reduced to 1485 mm. The curb weight of the trailer is determined at 18 tons, the weight of the cargo is 63 tons. The total weight, respectively, reaches 81 tons.
The MZKT-74135 + 99942 + 83721 three-piece road train tank carrier is distinguished by the most remarkable dimensions and weight, and also has unique characteristics. The tractor, semi-trailer and assembled trailer have a length of 38.6 m. The curb weight of such a complex is slightly less than 50 tons. The payload is 133 tons. The total weight is about 203 tons.
Moving along the highway, a tank carrier with a semitrailer and a load on it can reach a speed of no more than 82 km / h. The maximum speed in full configuration is limited to 50 km / h. The special design of the running gear and its individual elements increase the cross-country ability of the road train. As has been shown in the tests of past years, such equipment is capable of moving not only along the highway, but also on a dirt road. It is also possible to overcome certain off-road sections.
The first prototype of the MZKT-74135 tractor, later equipped with the MZKT-9942 semi-trailer at the beginning of the last decade, was able to show the highest performance and interest a potential customer in the face of the United Arab Emirates army. Based on the results of those tests, even with a noticeable delay, an agreement was signed on the modernization of the existing equipment with its subsequent serial production. In accordance with the first order, the Minsk Wheel Tractor Plant produced 40 complexes for the ground forces.
In 2007, a new contract appeared for the tank carriers MZKT-74135 + 99942 + 83721. This time, the UAE has requested the supply of two hundred tractor units with semi-trailers and trailers. For several years, such an order was fully completed. The supply of a significant number of special equipment of Belarusian production in a known way affected the mobility of the UAE ground forces. The increased carrying capacity of the new road trains makes it faster and easier to transfer military equipment, which has a positive effect on the combat effectiveness of troops.
In 2016, foreign publications mentioned a new order from the UAE Ministry of Defense, according to which the army will receive a certain amount of special equipment. It was argued that this time the Republic of Belarus will receive a contract without competition and comparative tests. According to some reports, it was again about road trains based on the MZKT-74135.
A characteristic feature of the MZKT-74135 + 99942 + 83721 road train and, first of all, of its basic tractor are advanced cooling facilities that ensure the operation of equipment in the difficult conditions of the Middle East. In this regard, the Minsk Wheel Tractor Plant continues to promote its development on the international market. However, as far as is known, so far only the United Arab Emirates was interested in such technology. Other states in the region are still unwilling to acquire the most interesting pieces of equipment with unique characteristics.
A three-link road train with the ability to transport two or three combat vehicles could be of interest to other countries, but they are still in no hurry to conclude contracts. Perhaps they are frightened off by the adaptability of ready-made samples for operation in hot climates, which is excessive for their conditions. However, it cannot be ruled out that Belarusian engineers will be able to redesign their road train in accordance with the requirements of the new customer.
At the moment, the MZKT-74135 + 99942 + 83721 road train tanker is one of the best vehicles of its class in the world. It shows unique technical and operational characteristics, having a serious impact on the combat capability of troops. At the same time, this sample of special equipment is not very popular. Over the years, only one country has ordered it. Such circumstances transfer the Belarusian road train to the category of remarkable, but not particularly successful developments. Will he be able to become the subject of new orders and get rid of such an unpleasant status - time will tell.
