Authored By Dan Alex (Updated: 7/15/2016):
The Centurion Arrives in War Torn Europe - Too Late
With war across Europe in full swing, the British War Office issued a requirement - under the designation of "A41" - for a new heavy cruiser tank in 1943. The excellent German "88" flak gun - at this point in the war now being used just as effectively as an anti-tank gun - forced the British to rethink their tank design formula and request a combat system that could withstand a direct hit from such a weapon. Additionally, the requirement called for a reliable battlefield implement with a maximum weight no greater than 40 tons to operate in conjunction with the 40-ton transport trailers available to the British Army at the time. As such, the new tank design would have to be well-protected along its critical facings with an appropriate displacement of armor which, in effect, would make for a heavier tank. Due to the carrying limitations of existing transport trailers (designated Mark I and Mark II) in the British Army inventory, the original 40-ton weight limit proved somewhat unfeasible for the armor requirement and was thusly expanded. Instead of limiting the design of their new tank proper - a tank the War Office believed would be a complete success from the beginning - it was decided to build all-new, heavy-class trailers instead.
The Centurion Mk I
The new design took the base 5-wheel suspended track system of the original Comet cruiser tank. The Comet was a relatively new design entering service only in 1944 and seeing additional combat in the upcoming Korean War. She was produced by Leyland Motors Ltd to the tune of 1,186 examples and was armed with a 77mm high-velocity main gun in a traversing turret. However, the tracked component of the Comet for the purposes of a new design was further extended to include a sixth road wheel and the original Christie suspension system was dropped in favor of a Horstmann suspension system. The coil-spring based Horstmann system saw its origins in an original British 1922 design by engineer Sidney Hortsmann. An all-new hull was affixed between the track installations that was specifically designed in such a way as to help with ballistics protection against the newer threats of the modern battlefield. Main armament would come from the proven 17-pounder (British 76.2mm) main gun. Interestingly, the designers fitted a 20mm Polsten cannon as secondary armament. The Polsten series was a cheaper - yet still effective - Polish-designed version of the excellent Swiss 20mm Oerlikon series cannon. To ensure excellent performance for the weight, the aircraft-based Rolls-Royce Merlin liquid-cooled V12 engine was reworked to become the Rolls-Royce Meteor powerplant. The Rover Company handled production of this new engine (later becoming the Leyland Motor Corporation) for the new British tank.
The Centurion Mk II
While construction of the original 40-ton pilot vehicles were already underway, a newer and heavier version was already in the works. The early pilot (prototype) vehicles emerged as 40-ton end-products and were designated simply as "Centurion Mk I". These early forms were armed with the aforementioned 17-pounder main gun. Production of the Centurion Mk I proved quite limiting however for the improved and uparmored Centurion Mk II was soon unveiled, this version with a cast turret. The Centurion Mk II promised better battlefield protection through use of more armor and serial production from a 800-strong government order was underway by the end of November of 1945. Production would be handled out of several British factories. The Centurion was formally accepted into British Army service in December of 1946 with the first proud recipients becoming the men of the 5th Royal Tank Regiment.
The Centurion Mk III
By the time the Centurion Mk II was finding its footing in the British inventory, the Centurion Mk III was developed thanks to the arrival of the new 20-pounder (84mm) tank gun furnished by the Royal Ordnance Factory. The addition of the more powerful weapon rendered the original Polsten 20mm cannon fitting of the previous Centurion designs moot and these were therefore replaced by a Besa tank machine gun instead. The Centurion Mk III was also a major upgrade to the preceding Mk IIs for it fitted a fully-stabilized gun control system for "firing on the move", further broadening the tactical scope of the new British tank. A new engine with more power was introduced as was a new improved gunsight. Production of the improved Mk IIIs commenced in 1948 and replaced all previous production marks in the field. Once in service and in available numbers, the Mk III was quick to replace the essentially outmoded Mk I and Mk II marks. Surplus Mk Is and Mk IIs then became subject of upgrade programs to Mk III standardization or converted into useful battlefield engineering vehicles to serve the new Mk IIIs and other heavy armored vehicles.
The Centurion Receives the L7 105mm Main Gun
While the new 84mm main gun proved a substantial upgrade to the original 76.2mm system, the Centurion was not done with its metamorphosis in becoming one of the finest tank weapons in the world. The Royal Ordnance Factory completed work on the all-new, revolutionary 105mm L7 rifled main gun which promised improved firepower through better penetration values than all other preceding British tank guns. The 105mm gun system was then quick to replace the 84mm in future Centurion production examples. The Centurion Mk 7 soon emerged with the L7 in place as production commenced and these were followed by the Mk 8/1 and Mk 8/2. In all, thirteen major Centurion marks would ultimately exist.
Centurion Mk I marked the early 17-pounder armed tanks based on the 40-ton prototype. The Mk II was fielded with its fully-cast turret. The Mk III was first given the newer 84mm main gun but this later gave way to the even newer 105mm L7 gun with gun stabilization and new sights. The Mk IV existed as a proposed close-support model fitting a 95mm CS howitzer cannon but never entered serial production. The Mk V/Mk 5 was the first to feature Browning machine guns at the coaxial and commander's cupola positions. Stowage bins along the glacis plate were also introduced with this mark. The Mk 5/1 brought about an increase to glacis armor thickness as well as introducing 2 x coaxial machine guns. One was a typical 7.62mm anti-infantry fitting while the other was a 12.7mm ranging heavy machine gun to help train the main gun (the the 84mm version) on a target. The Mk 5/2 utilized the 105mm L7 main gun. The Mk 6 was an uparmored version of the Mk 5 with the 105mm L7 main gun in place. The Mk 6/2 sported a ranging gun for improved accuracy. The Mk 7 saw its engine compartment rood redesigned. The Mk 7/1 was nothing more than an uparmored Mk 7 while the 7/2 was an upgunned Mk 7 (105mm L7). The Mk 8 was given a new mantlet and revised commander's cupola. The Mk 8/1 sported more armor and the Mk 8/2 was fitted with the 105mm L7 main gun. The Mk 9 was an uparmored Mk 7 with the 105mm L7 main gun. The Mk 9/1 fitted infra-red equipment while the Mk 9/2 sported a ranging gun. The Mk 10 was an uparmored Mk 8 with the 105mm L7 main gun. The Mk 10/1 was fielded with infrared equipment and the 10/2 was given a ranging gun. The Mk 11 was an Mk 6 model with the ranging gun and infrared equipment. Similarly, the Mk 12 was an Mk 9 model with the ranging gun and infrared support. The Mk 13 was an Mk 10 with the ranging gun and infrared support.
Armored recovery vehicles were designated as Centurion ARV (Mk I and Mk II) while the Centurion Ark (FV 4016) was a bridgelayer type implement as was the Centurion AVLB (Dutch Army service) as was the Centurion Bridgelayer (FV 4002). The Centurion AVRE 105 and AVRE 165 were combat engineering vehicles each armed with a 105mm and 165mm demolition gun respectively. The Centurion BARV was a "Beach Armored Recovery Vehicle". Other British Army variants further expanded the Centurion family line.
Centurion Global Operators
Complete operators of the Centurion main battle tank (beyond the British Army) became Australia, Austria, Canada, Denmark, Egypt, India, Iraq, Israel, Jordan, Kuwait, Lebanon, Netherlands, New Zealand, Singapore, Somalia/Somaliland, South Africa, Sweden and Switzerland.
The Centurion Oliphant of South Africa
The Centurion was rebuilt in South Africa with French assistance (due to a 1970s UN military embargo on the African nation) as the "Olifant". First versions appeared in 1974, this as the Semel with a 810hp engine. The primary versions then became the Olifant Mk I of 1978 (with a 750 horsepower engine), the Olifant Mk 1A of 1985 (laser-rangefinder and image-intensifier), the Olifant Mk 1B of 1991 (with torsion bar suspension, longer hull, improved armor, digital fire contol, laser rangefinder and 950 horsepower engine) and the Olifant Mk 2 (new turret and fire control system, 105mm or 120mm main gun as needed). To date, the Olifant is still considered the most advanced combat tank on the African continent - and few could argue that. South African weapons engineers had made a habit of modernizing existing systems into more potent forms - even in the face of imposed sanctions on weapons and technology.
The Centurion Sho't of Israel
The Israelis designated their Centurions as the Sho't. This included the Sho't Meteor to signify this Mk V's use of the original Rolls-Royce Meteor engine and several modernization attempts that spawned the Sho't Hal Alef, Bet, Gimel and Dalet. The Nagmashot, Nagmachon and Nakpadon were armored personnel carrier conversions of the base main battle tanks. The Puma designated combat engineering vehicles while the Eshel ha-Yarden was a proposed Centurion development fitting 4 x 290mm launch tubes for battlefield rockets.