With the Cruiser Tank Mk IV, the British Army found a replacement for its limited-value Mk III series. However, the Mk IV was nothing more than an up-armored Mk III and did little in the defense of France with the British Expeditionary Forces (BEF). It did go on to raise its combat stock in the ensuing campaigns of the North African Theater but production was still limited as was its overall combat value as the World War 2 (1939-1945) evolved.
A new direction was found when it came to the succeeding "Cruiser Tank Mk V Covenanter (A13 Mk III)" as a new hull and turret design were implemented. The Nuffield Liberty gasoline engine was given up for a Henry Meadows D.A.V. "Flat-12" engine of 340 horsepower. Its radiators were mounted at the front of the hull with the engine at the rear (a rather detrimental design aspect). The engine was mated to a Meadows transmission gearbox with Wilson epicyclic steering system. The Christie suspension system was retained as were four large, steel road wheels within the "track-and-wheel" running gear. Armor protection was increased from 30mm seen in the Mk IV to 40mm in the Mk V at its thickest facing. Main armament was still a QF 2-pdr (40mm) main gun with a coaxial 7.92mm Besa machine gun. Overall range was 100 miles with a road speed topping 30 miles per hour. While the Mk IV weighed in at 16.5 tons (short), the newer Mk V vehicle proved a much heavier combat platform at 20 tons. Its crew numbered four - driver, commander, gunner and loader.
Design work on the vehicle began in 1939 and was handled by London, Midland and Scottish Railway (LMSR), a heavy industry group founded in 1923 (defunct in 1947). Britain was not yet fully at war but measures were already being taken in preparation. The tank was approved and adopted for production with 100 vehicles on order, this before a single prototype were built. Of note is LMRS held no experience in the design and manufacture of combat tanks. The LMSR tank exhibited many angled surfaces for basic ballistics protection as well as a low profile to present a harder target to hit. Welding was to be used for the hull construction (as opposed to riveting). The British Army expected two pilot vehicles for testing while manufacture would begin in earnest.
Several notable factors were encountered during the design, development and eventually production of the Covenanter which led to its downfall as a viable combat system. The manufacturer convinced authorities to revert back to an easier riveted-hull approach and heavier steel wheels substituted the originally-intended, lighter-weight aluminum types (aluminum now ear-marked for aircraft production). The Covenanter's low profile design meant that a low profile engine was needed and this, in turn, forced cooling radiators to be mounted at the front of the vehicle, degrading engine cooling, and limiting the tank's hot climate usefulness due to constant overheating engines. Overall weight of the combat vehicle eventually ballooned due to the added features, heavier wheels and armor protection, stressing the suspension system under a standard load.
Testing continued into 1940 with the two promised pilot vehicles. Hulls were appearing as expected though there were delays in obtaining completed turrets. The Covenanter was therefore delayed into service and those that emerged were given to British Home Guard units and relegated to training roles. Production eventually yielded 1,700 examples though none were actually sent into combat. By 1943, the line was considered obsolete by virtue of its armor protection and small-caliber armament, especially when compared to the variants of German Panzers appearing. As it stood, the Covenanter never fully resolved its engine cooling issues and was now an under-armored and under-armed combat tank with little battlefield value as the war went on. Second-line models continued on in service into 1945, some even seeing service during the Pacific Campaign with Australian armored forces.
Despite its rather non-existent combat career, the Covenanter appeared in many notable variants during its service life. Covenanter Mk Is were original production marks with the Covenanter Mk I CS serving as a close-support model armed with a 3-inch howitzer. The Covenanter Mk II was an Mk I with additional radiator-mounted coolers and the Covenanter Mk II CS was its close-support version. An OP ("Observation Post") variant was brought along with additional communications equipment and a "dummy" main gun armament. A similar Command Vehicle also emerged. The Covenanter Mk III introduced some clutch changes, twin oil coolers for the engine and mufflers were relocated rearwards. The Covenanter Mk III CS was its close-support form. The Covenanter Mk IV borrowed some clutch changes from the Mk III and the Covenanter Mk IV CS was its close-support variant. The Covenanter ARV Mk I was an Armored Recovery Vehicle form sans the Covenanter's turret though only one pilot vehicle was completed during 1942. The Covenanter AMRA Mk IC was an "Anti-Mine Roller Attachment", mine clearance vehicle. The Covenanter Bridgelayer was just that, a bridge-laying variant featuring a 34-foot span bridge hinged as two halves. These managed extended war-time service lives even after the main Mk V combat forms had been removed from service.
The Mk V became the first British cruiser tank to be named (other offerings were simply known by their "marks" as Mk I, Mk II and so on). The "Covenanter" name was derived from the British Isle Scots encountered during the "Wars of the Three Kingdoms", this conflict encompassing the nations of England, Ireland and Scotland. The wars were fought from 1639 to 1651.