Tanks Chieftain History and Description of The Design

Tanks Chieftain
   History and description of the design

Postwar trends of the world tank tactics and the development of tanks convincingly showed that “dvuhtankovaya theory” is outdated. In England, the development of main battle tank (project FV4201), capable of change, and the average “Centurion” and the heavy “Konkeror, begun in 1957 (the technical specification for the tank, designed to replace the” Centurion “and” Konkerora “was formulated in 1956), almost simultaneously with the commencement of works on Leopard-1 “in Germany and AMX-30 in France.

The approach to the design of the British main battle tank was quite different from that in other European countries. The end of the 1950’s. coincided with the general enthusiasm missile weapons. It was believed that the rocket does not protect any armor, and therefore priority should be given to high-speed qualities at the expense of security. On this path went tank-builders from the continent. The British, as it should be the Conservatives, rightly thought that the advent of missiles does not abolish the normal tube artillery and mines. At the British was impressed by the experience gained in the use of tanks “Centurion” in Korea, where the thick armor than once saved the life of the tanks. Based on the experience of the Korean War, the British have done the basic conclusion: the perspective of the tank body armor in any case should not be sacrificed in the mobility and firepower, and the thickness of armor – not to yield to that of Centurion. In this case the British wanted to get the same maneuvering characteristics as their counterparts from France and Germany, and the firepower to beat them. But the combination of thick armor and powerful gun led to a sharp increase in weight of the tank, which, in turn, would force designers to seek such technical solutions that would help with the data requirements for combat vehicle to improve its mobility.

Main Battle Tank Chieftain “(” commander “), as well as Centurion, designed by specialists of the State Scientific-Research Institute of tanks – FVRDE (Fighting Vehicle Research & Development Establishment) in cooperation with the firm’s engineers” Leland “and” Vickers . The latter was responsible for the development of the tower. Two years after the initial design, in 1959, the state tank factory (Royal Ordnance Factory) in Leeds was built a prototype tank, testing which began in 1960 in 1962 ended in combat tests of six prototypes, and in May 1963 g. “Chieftain” was adopted by the British army. Its production at two facilities – the state in Leeds and the firm Vickers-Armstrong at Newcastle. From 1966 to 1978 for the British army was made 770 such tanks.

Tank Chieftain has a classical layout: separation of management – in the front, fighting – in the middle, MTO – in the stern. Housing welded, poured and rolled parts. On the armor accounts for approximately 53% of the mass of the tank. Upper frontal body part has a thickness of 120 mm, Depth – 38 mm, rear leaf – 25,4 mm, bottom – 16 mm. Tower of cast, the thickness of its front part – 195 mm, the roof – 45 mm.

Strengthening the protection of the tank achieved not only increase the thickness of armor, but a rational arrangement of the armor plates, a sharp decrease in the height of the machine and its internal volume. The frontal piece shell is tilted 72 ° to the vertical side plates set at an angle of 10 °, the angle of inclination of the frontal part of the tower – 60 °. Tower of rather complicated form: the design as if it were built around the crew and equipment, which she, so to speak, “flowed” to reduce the surface area. A similar concept was used in the design of the towers of the Soviet tanks T-64 and T-72.

Embrasure under the gun made a width of only 225 mm, thereby managed to minimize the weakened area in the frontal part of the tower. For the first time in the world tank building a driver located reclining, as a result of the height of the front part of the body was able to reduce up to 1,178 mm, while increasing the slope of the frontal bronelista. To enhance the protection of mines seat driver attached to the armor-plate, at a distance of 50 mm from the bottom of the case – thus obtain local booking spaced bottoms. The form of the hull and turret “Chieftain” is the most successful among all western tanks 1960 – 1970’s.

Workplace driver is in the department of management and is located on the axis of the tank. The back seat driver can be installed in three fixed positions with a slope of 45 °, 50 ° or 55 °. In position “in its stowed position, the open upper hatch, the seat goes up and back takes position with the angle of inclination of 55 °. Office corner of the tank by means of two levers, adjustable, like the seat back, the angle of inclination. In a closed hatch a driver is an overview of the surrounding area through a fixed wide-angle periscope observation instrument.

In the rotating turret of a three-centered main and auxiliary armament of the tank. It should be emphasized that the full development of the “Chieftain” was preceded by a detailed analysis of weapons and body armor the most successful heavy and medium tanks of the world (as priority goals for the new guns were considered the tanks). The results showed that the most effective destruction requirements are well armored targets at ranges over 2000 meters will be responsible rifled gun 120 mm. Distance of 2000 m was chosen based on the conditions of the European theater, where most visibility reduced to 4000 m, while the majority of small targets such as tanks or APCs, found at a distance of 2000 m.

Work on such a gun began in the state tank factory in 1954, and by the beginning of the development of Chieftain 120-mm tank gun L11 length of 55 calibers was almost ready. The decision to install such a powerful weapon in the main battle tank, adopted by the British, quite radically different from the views of other European designers, arming their cars 105-mm guns L7. We can assume that the British in regard to weapons and body armor Chieftain looked at least ten years – fifteen forward: close “Chiftenu” on security and arming Western tanks (for example, “Leopard 2″) appeared only in the late 1970’s.

It is difficult to say to what extent the tank-builders used the services of technical intelligence, or just the designers who solve similar problems on different sides of the Iron Curtain came to similar conclusions, but in the late 1950’s. and Soviet engineers have worked on projects tanks weighing 60 – 70 tons, armed with 130-mm rifled gun. Thus, the British concept of the main tank was much closer to the views of Soviet engineers and the military, than the West.

Corners of an instrument in the vertical plane are on “Chiftene” -10 ° to +20 °. Installed a heat gun on the guard and ejector for purging the bore after firing. The barrel is made of stainless steel by electroslag remelting, and is designed for 550 shots. 120-mm gun L11 has separate loading. Powder charges are completely burning bags, like a ship’s cannon shots. Ammunition (projectile-charge) to 120-mm gun weighs less and takes up less space than a unitary fired 105-mm gun L7. Ignition when firing takes place with the glow-tubes, fed automatically from the breech gun. Capacity in the mechanism of supply – ten tubes. The loading guns by hand, using hydro-mechanical rammer. Of vertical wedge gate opens automatically when you reel the barrel after firing. An experienced crew can produce from an instrument to eight rounds per minute. The best is the following modes of fire: the first minute – ten shots, the next four – six, then – a break to cool the barrel. Especially for new tools were developed two types of ammunition: AP Subcaliber L15A4 and armor-piercing high-explosive L31 with plastic explosives and deformable warhead. Armor-explosive fragmentation projectile given special attention, because this round was considered a universal, replacing traditional high-explosive shells, and cumulative. Ammunition – 53 rounds. Maximum speed rotation of the tower 22 degrees. / S, pointing guns in the vertical plane – 5 deg. / Sec. Drives Guidance – electric. Muzzle velocity L15A4 – 1370 m / s, projectile L31 – 670 m / sec. The first tanks were paired with a gun, two guns: one L8A1 caliber 7,62 mm shall be left of the gun and one L21A1 caliber 12,7 mm – over gun.

Cannon and machine-gun stabilized in two planes. Stabilization system is developed based on a similar system tank Centurion. Despite the stabilization of the guns, the main mode of fire is shooting from the spot. The fire control system enables the gunner to approach the turn of opening fire build a weapon at the target, stopping only need to work a shot from a cannon. The height of the fighting compartment floor to the roof of the tower is 1730 mm. The commander and gunner are on the right from the gun, loader – on the left. When firing the loader works standing up. I installed the main gunner monocular periscope sight “Barr End Strood» TLS № 9 Mk.1 with 1 – and 10-fold magnification and backup telescopic optical sight AFV № 26 Mk.1 with a 7-fold increase, both the sight are independent stabilization of the visual field in the horizontal plane. Binocular periscope optical sight commander with 1 – or 15-fold increase in AFV № 37 Mk.3 mounted in front of the commander of a rotating turret. Through the optical channel commander can mark the current target in the field of view of the gunner’s sight. Aiming weapons is possible as the gunner and commander, with the latter considered a priority action. Instead, the commander daytime optical sight can be set active night vision device with illumination from the infrared searchlight. In the stowed position night vision device and the spotlight is stored in the outer box on the left side of the tower.

The distance to the target at distances up to 2000 m is determined using the included adjustment 12,7 mm machine gun. When firing high-explosive shells from the closed positions require training data, as in the firing of conventional towed guns. Commander’s cupola for better retention goals in sight and the convenience of observation at the turn of the tower rotates in the opposite direction of rotation, while maintaining the line of sight, time for a complete reversal – 16. In the tower has nine fixed periscope observation devices AFV № 49 with the total field of view of 360 °. Commanding hatch – bicuspid. Review of the loader is provided through a periscope observation instrument circular rotation AFV № 30Mk.1.

The sides of the front of the tower mounted two six-barreled 66-mm smoke grenade. In the rear recess of the tower are two radio stations: “Plassey” P.42 VHF range and short-wave “Plassey” V.47. The latter provides a stable connection within a radius of 8 km and is 181 feed. VHF 481 is a channel of communication, it is integrated tank intercom. The possibility of connection to the Tank intercom field telephones, which in the after hull plates have special connectors. The tank is equipped with a system of protection against weapons of mass destruction and fire-extinguishing system.

In MTO installed 6 two-stroke multi-cylinder liquid-cooled diesel L60 company “Leyland” power of 585 hp It has a vertical arrangement of cylinders, one cylinder, there are two oppositely moving piston. The engine is in normal conditions with electric start, in the cold – gidrostarterom or auxiliary diesel. Job electric and gidrostartera, backup electric starter, provides support 3-cylinder boxer diesel Coventry Climax “Nzo № 4 30 horsepower Transmission – mechanical TN-12 firms “Merritt-Wilson. The gear shift is a foot pedal. Internal volume MTO about 6 m3. To facilitate the maintenance of diesel engine, transmission, radiators, fans, cooling system, oil filter and some other units are mounted in a single unit, to replace that in the field requires 30 minutes. Engine to be replaced after 5000 kilometers, air filters need to be replaced every 1,500 kilometers.

Chassis Chieftain almost identical to the chassis of the tank Centurion. For incomprehensible reasons, the designers are out to make a machine that exceeds all the European mass tanks, but not inferior to them in agility, did not develop a new suspension, although by early 1960 it was clear that the spring-equalizer suspension Centurion “no provision for upgrading and it is largely obsolete.

Chassis includes six road wheels and a rear-drive wheels. Dvuskatye road wheels with rubber tires and removable steel discs. Supporting rollers (three on board) and gable, shaft. Driving wheels are equipped with removable steel-toothed crowns (to 12 teeth on the crown). Caterpillars – with open joints sequential type and replaceable rubber pads (one per truck). Track tensioning mechanism – crank-type worm. Resource chassis elements is 2 – 5 thousand km. The lower limit (2000 km) is determined by the reliability of the open-hinge larvae, the upper (5000 km) – teeth crowns of driving wheels. Chassis for protection against cumulative light antitank weapons covered by a four-steel screen thickness 10 – 15 mm.

The concept of well-armored tanks with powerful weapons and limited mobility, ie the tank “Chieftain”, has caused, to put it mildly, a mixed reaction among Western military experts and tank. The storm of criticism descended on the maneuvering characteristics of the machine. This superiority Chieftain of the Leopard 1 and AMX-30 in protection and firepower are often simply ignored.

It should be noted that many discussions on how to use various weapons systems in the European theater had about the same relationship to reality, like the famous question: “Is there life on Mars?” – Is also very popular in 1960. And West Europeans, and our people seriously going to fight is unlikely. The main emphasis was not to achieve victory in war, but to avoid the war. So, fortunately, all these discussions both on paper and left. But representatives of the State of Israel did not deny the possibility of war, they are seriously going to fight until victory. In the mid 1960’s. Western countries freely supplying military equipment to the Promised Land, so that the choice of the Israelis was. Replace the aging “Centurions” was impossible and American cars, and leopard, and AMX-30, and “chiftenami. However, the purchase of military equipment in Germany would hardly understand the people of Israel – the ashes of Auschwitz, Babi Yar and Majdanek are “knocking at the heart” of many Jews. But the French tank was well within the then dominant theory of the mobile machine with good arms. In addition to the arsenal of Israel Defense Forces consisted of many French AMX-13 tanks. Yet the Israelis have chosen “Chieftain”. From October 1966-th to 1968 in Israel conducted a detailed evaluation tests of two British machines. The results of the 1967 war, only to convince the Israeli experts in the correct choice. Main – gun and protection, and mobility on the battlefield is determined not so much a performance chassis, as thick armor. In 1969, the Israeli government formally requested the British request for the supply of tanks Chieftain. But the events of 1967 dramatically altered the state of Israel in the world – it has almost become a rogue state, which is open only helped the United States. England was unable to break the embargo on military equipment here.

Perhaps, the fact that tests of two British tanks in Israel and does not deserve such a serious consideration: how many such events took place and is held constant in the world. But in this case, the Israelis were in the role of impartial judges, and their final decision in favor of “Chieftain” allows you to put an end to the protracted dispute: which of the three European tanks of the second postwar generation better. Military and Israel’s policy has always primarily evaluate the qualitative characteristics of weapon systems and only then raised the question of cost, or about political ethics. Ignoring the last factor, for example, resulted in the adoption of a captured T-55 tanks and T-62.