Chapter Three

Cruiser Tanks

The cruiser tank–sometimes called the ‘cavalry tank’–was seen as a medium-weight, fast machine which could make reconnaissance forays deep into enemy territory, much as horse-mounted cavalry had in former conflicts.

Modern thinking on tank design demands that equal attention be paid to mobility, firepower and protection. These principles were not as well accepted in the mid-1930s when the concept of the cruiser tank was first mooted and the emphasis on the speed of the cruiser tank was generally at the expense of armoured protection and firepower–for the first years of the war, British cruisers were armed only with a 2-pounder (40mm) anti-tank gun.

As the Second World War progressed, the role of the cruiser tank, as originally envisaged, became less and less clear and battlefield experience showed that the cruisers were vulnerable to more powerful German anti-tank weapons–the fearsome 88mm KwK L/56 gun of the Tiger being an extreme case in point. The 2-pounder (40mm) gun was soon replaced by a 6-pounder (57mm) and then, in some cases, by 75mm, 77mm and 17-pounder (76.2mm) guns in an effort to engage German armour on equal terms. Of these, probably only the 17-pounder (76.2mm) and the related 77mm were superior to the German 88mm, particularly when firing armour-piercing discarding sabot (APDS) rounds.

Eleven cruiser tank designs were produced between 1934 and 1945. Some never saw enemy action at all and were retained for training purposes; others saw action but were no match for the German machines. Only two of the designs were really satisfactory–the Meteor-engined Cromwell and the up-gunned Comet variant.

Cruiser Tank Mk I (A9)

What became known as the A9 cruiser tank Mk I was originally conceived as a medium tank to replace the Vickers A6 medium tanks Mks I and II. Development work had started in 1934 under the direction of Sir John Carden of Vickers-Armstrongs, with a view to coming up with a cheaper and more effective design. The A9 was notable for being the first British tank to incorporate a ballistically designed hull, albeit that the maximum thickness of armour was not sufficient and the machine-gun turrets were vulnerable. It was also the first to be fitted with a centrally positioned hydraulically powered turret, and was the first to incorporate the Vickers-Gerlach tank periscope, rather than using direct-vision heavy glass blocks. The A9 was also a pioneer in deep wading and, in 1939, one example was successfully driven completely submerged.

The tank was relatively small: the low hull had a length of just 231in and a width of 100in. Riveted construction was used throughout, with a maximum thickness of armour of 14mm, giving a combat weight of around 12 tons. There was no separation of the driving and fighting compartments and the hull must have been a tight fit for the standard six-man crew. Vickers had proposed that a Rolls-Royce Phantom II engine be used, but production vehicles were powered by a rear-mounted AEC A179 six-cylinder petrol engine, producing 150bhp from 9,630cc, and driving the rear sprockets through a five-speed manual gearbox. Utilising the Vickers ‘slow motion’ suspension, the road wheels were arranged in threes on a pair of bogies, the front and rear wheels on each side being of larger diameter. A large single spring was provided for each bogie, together with a Newton and Bennett telescopic hydraulic shock absorber. Top speed was in the order of 25mph on the road and 15mph across country, with a range of 100–145 miles.

For the prototype, the main gun was a 3-pounder (47mm) but all production vehicles were armed with the standard 2-pounder (40mm), together with three Vickers .303in water-cooled machine guns: one coaxial with the main gun, the other two in auxiliary turrets on either side of the hull. A fan was fitted in the hull to clear the gun fumes. There was also a close-support variant–cruiser tank Mk I CS–which mounted a 3.7in howitzer in place of the standard 2-pounder (40mm) gun.

A total of just 125 vehicles were constructed: fifty by Vickers-Armstrongs and sevnty-five by Harland and Wolff in Belfast. The Mk I cruisers saw service in France in 1940 and in the Middle East the following year; however, although the main gun was effective against the Italian tanks, it was no match for the more sophisticated German machines. The crews also complained that the design was unreliable and was prone to shedding tracks.

Cruiser Tank Mk II (A10)

Three months after starting work on the A9, Sir John Carden’s team at Vickers-Armstrongs began designing an infantry version, designated A10. However, despite the armour being increased to a maximum of 30mm using bolt-on plates, the design was felt to be inadequately protected for the infantry-support role and it was reclassified as a heavy cruiser, becoming the cruiser tank Mk II. Even as a cruiser it was not successful, however, and despite the suspension being found to work well in the desert, the War Office criticised the machine for being slow and underpowered, with a poor cross-country performance.

In design the hull was similar to the A9, although the auxiliary machine-gun turrets were omitted, which allowed the crew to be reduced to five. The Vickers ‘slow motion’ suspension was retained, as was the AEC A179 petrol engine and the five-speed transmission. Measuring 217in in length, making it slightly shorter than the A9, but with the width identical at 100in, the additional armour put the weight up to 13.75 tons, having the effect of bringing the top speed down to 16mph on hard surfaces and 8mph off the road.

The main gun was the 2-pounder (40mm); there was also a single coaxial Vickers .303in water-cooled machine gun, and a 7.92mm Besa machine gun in a barbette to the right of the hull, making it the first British tank to be fitted with an air-cooled machine gun. On the Mk IIA there was an armoured radio housing and a redesigned mount for the main gun; the Vickers machine gun was also omitted in favour of a second 7.92mm Besa machine gun. As with the A9, there was also a close-support variant (cruiser tank Mk II CS) mounting a 3.7in howitzer.

Production started in 1938, and the type was built by Vickers-Armstrongs (ten), Metropolitan-Cammell Carriage and Wagon Company (forty-five) and the Birmingham Railway Carriage and Wagon Company (120). Like the A9, the A10 was never considered to be more than a stop-gap measure whilst the A13 was developed.

Cruiser Tank Mk III (A13)

The cruiser tank Mk III was probably the most significant British tank of the interwar period and made much of what had gone before redundant. Developed by Morris Commercial Cars and constructed in small numbers by the company’s newly established munitions subsidiary, Nuffield Mechanizations and Aero, it was the first British tank to incorporate the suspension that had been designed by the American J. Walter Christie. Using a combination of short swinging arms bearing against long coil springs, the suspension gave the tank a standard of off-road performance that was far in advance of anything previously seen in a British tank and the Christie suspension went on to be used on all subsequent British cruiser tanks.

Although Morris Commercial had been supplied with two Christie tanks from the USA during 1936, the hull of these machines was considered to be too small to accept the typical British turret and the decision was made to incorporate the suspension into a completely new hull. The opportunity was also taken to incorporate Newton and Bennett telescopic hydraulic shock absorbers. The A13 was powered by a rear-mounted Nuffield Liberty V12 tank engine, the origins of which went back to an aero engine designed in 1917. With a power output of 340bhp from a capacity of 27,022cc, the engine was coupled to the rear sprockets via a four-speed manual gearbox. In prototype form, the vehicle was capable of a maximum speed on the road of more than 35mph, with 25mph achievable across country–this led to various mechanical problems. Eventually the road speed was governed to 30mph; in conjunction, the transmission was modified and the tracks redesigned, with a shorter pitch between links.

With an overall height of 100in, and an overall length of 237in, the A13 seemed long and low, an illusion reinforced by the large-diameter road wheels that also served as track-return rollers. The turret was similar to that fitted to the A9 and A10, and the main gun was the familiar 2-pounder (40mm), together with a coaxial Vickers .303in water-cooled machine gun. The maximum thickness of armour was just 14mm, giving a battle weight of 14 tons.

Trials began in October 1937; in January 1938, even before the trials were completed, sixty-five vehicles were ordered, with deliveries scheduled to begin in early 1939.

Cruiser Tank Mk IV (A13 Mk II)

With the design redesignated as A13 Mk II, the cruiser tank Mk IV was fitted with a new style of turret that incorporated distinctive V-section side plates to give a spaced armour configuration. At the same time, new minimum requirements for the armoured protection of cruiser tanks resulted in the maximum thickness of armour on the hull being increased to 30mm, raising the total weight of the vehicle to 14.75 tons. Some examples were built with additional armour covering the gun mantlet. Whilst the turret may have been redesigned, the main gun was still the 2-pounder (40mm), and there was also a coaxial Vickers .303in water-cooled machine gun, which, on the Mk IVA, was replaced by a Besa 7.92mm machine gun. A close-support variant was also produced, mounting a 3.7in howitzer and designated cruiser tank Mk IV CS. The engine, transmission and running gear were unchanged and, despite the increase in overall weight, the maximum road speed remained 30mph.

Some sources suggest that the total production amounted to 655 vehicles, of which 455 were produced by Nuffield Mechanizations and Aero, and a further 200 by the London Midland and Scottish Railway (LMS) workshops, English Electric and Leyland; others suggest that the figure was 240. The A13 Mk II was withdrawn from active service at the end of 1941, but remained in use as a training vehicle.

Cruiser Tank Mk V (A13 Mk III)–Covenanter

In June 1937, two new designs of cruiser tank were planned–the A14, which was to be powered by a Thornycroft marine engine, and the A16, which was to be fitted with the Nuffield Liberty engine. A prototype for the A14 was constructed before both designs were then cancelled and replaced by the lighter and cheaper cruiser Mk V, or A13 Mk III, subsequently dubbed Covenanter. This was the first of a long line of British tanks to be given names beginning with ‘C’ but the actual choice of this particular name is curious–apparently referring to a group of seventeenth-century Presbyterians who committed themselves to keeping their form of worship as the sole religion of Scotland, signing a covenant to this effect in 1638 and thus risking their lives.

Despite the Mk III designation, the Covenanter owed little to earlier versions of the A13 beyond the Christie suspension. The four-man vehicle had a redesigned hull with a lower profile, and incorporated increased thickness of armour. It had originally been planned that the hull would be welded, and the pilot model was constructed in this way, but a shortage of manpower and doubts about the strength of the welds led to a return to riveted construction using a sandwich of two plates. Nuffield Mechanizations also came up with a better-designed turret which used angular plates for improved performance against ballistics. The maximum thickness of armour was 40mm, giving a combat weight of 18 tons–this was more or less at the limit of the suspension, and led to unacceptable ground pressure.

The Nuffield Liberty engine of the earlier A13 variants was ousted in favour of a specially designed Meadows DAV tank engine, a horizontally-opposed twelve-cylinder unit producing 280–340bhp, that drove the rear sprockets. Also from Meadows, the transmission consisted of a four-speed gearbox together with a Wilson epicyclic steering unit; earlier plans to use a Wilson gearbox were abandoned due to fears about production. The width of the engine left little space in the engine compartment, and the radiators were positioned at the front, leading to cooling problems throughout the life of the vehicle. Top speed on the road was 30mph, reducing to 25mph when operated across country.

The 2-pounder (40mm) gun was retained, and secondary armaments included either one or a pair of 7.92mm Besa air-cooled machine guns.

A wooden mock-up was approved in late 1939 and production contracts were placed almost immediately, even before the first of two pilot models had been completed. The first of a total of 1,771 production vehicles appeared in late 1940. Production was undertaken by the LMS workshops, along with English Electric and Leyland under LMS design parentage. Although the Covenanter was used to re-equip the British 1st Armoured Division, the type never saw service outside the British Isles and was almost certainly never used in combat–although one example was destroyed by enemy action during an air raid!

The basic gun tank was produced in four variants in an attempt to solve the cooling problems: the Covenanter I was the original production version, and this was followed by the Covenanter II (cruiser tank Mk V*), III (cruiser tank Mk V**) and IV. A close-support version was produced with a 3in howitzer in place of the 2-pounder (40mm) gun, and a number of Covenanter I and II gun tanks were fitted with a 30-foot long hydraulically launched scissor bridge and used for training and development work. A Covenanter was also used for initial trials of the anti-mine roller attachment (AMRA), and a small number of obsolete vehicles were converted to observation post, armoured recovery and command vehicle roles.

Cruiser Tank Mk VI (A15)–Crusader

Following the abandonment of the A14 and A16 projects, Nuffield Mechanizations and Aero was asked to concentrate on the design of the A15, which, despite still being fitted with the 2-pounder (40mm) gun, was described as a heavy cruiser. Design work took place during 1938/39, and approval to construct a prototype and 200 production vehicles was given in July 1939, with the pilot to be delivered in March 1940. In order to speed the model into production, the design was based on the A13 Mk III, with the hull lengthened to include an additional wheel station to improve its ditch-crossing performance, and with the Meadows engine replaced by the V12 Liberty engine which had been used in the cruiser Mks III and IV and which was already in production. The transmission consisted of a four-speed gearbox, with a Wilson epicyclic steering unit.

There were three versions of the Crusader gun tank. Crusader I was the original production model, with a 2-pounder (40mm) gun mounted in an angular turret. There was also a front machine-gun turret, which was often removed in service, designed to mount a 7.92mm Besa machine gun; a second Besa machine gun was fitted in the turret, coaxial with the main gun. On the Crusader II (cruiser tank Mk VI A), the machine-gun turret was never fitted, but there was additional frontal armour on the hull and turret; on the Crusader III, the 2-pounder (40mm) gun was replaced by a 6-pounder (57mm) weapon, and the hull and turret armour were improved. Close-support versions of both the Crusader I and Crusader II were also produced, with a 3in howitzer replacing the 2-pounder. Other variants included a Crusader-based command vehicle and several types of anti-aircraft tanks mounting Bofors and Oerlikon weapons. Surplus and redundant Crusaders were also converted to the gun tractor, ‘dozer, ‘dozer/crane and armoured recovery vehicle roles, as well as being used for experimental work. A number of surplus Crusaders were fitted with the Rolls-Royce Meteor engine during the development of the Cromwell.

The Crusader was a low and compact design, with a riveted hull, and measured 236in long and 104in wide, with an overall height of 88in. The maximum thickness of armour was 40mm, subsequently upgraded to 49mm, and then 51mm, on the Crusaders II and III respectively. The turret was welded, with additional armour plates bolted to the sides. The battle weight of the Crusaders I and II was 19 tons, with the Crusader III tipping the scales at 19.75 tons; the radius of action was around 100 miles, or 125 miles with additional external fuel tanks.

The Crusader remained in production until 1943, by which time nine companies had been contracted to build a total of 5,300 vehicles under Nuffield’s design parentage.

Cruiser Tank Mk VII (A24)–Cavalier

By late 1940, the inadequacies of earlier cruiser tanks had highlighted the desperate need to improve both the armour and the main gun, and a specification was drawn up for a new heavy cruiser tank. The specification called for a maximum thickness of armour of 65mm on the front of the hull, and 75mm on the turret front, which provided approximately 50 per cent more armour than the Crusader. The puny 2-pounder (40mm) gun was to be replaced by a 6-pounder (57mm), which required a larger turret and turret ring. It was also suggested that a new, more powerful engine be fitted to improve the maximum speed.

Three companies competed for the work. Vauxhall Motors proposed developing what would have been a scaled-down version of the Churchill infantry tank, designated A23, whilst both the Birmingham Railway Carriage and Wagon Company and Nuffield Mechanizations and Aero came up with a variation of the Crusader. Since the Crusader was already in production, Nuffield was asked to construct six pilot versions of a model described as the A24 by the autumn of 1941, with subsequent production provisionally allocated to Nuffield and Ruston and Hornsby. Nuffield had little choice but to use an uprated version of the old V12 Liberty engine already seen in the Crusader, though it now produced 410bhp in the Mk IV form. The design also shared the gearbox, Wilson epicyclic final drive and improved Christie suspension arrangements with the Crusader.

Whilst Nuffield had been busy with the pilot models, Leyland Motors, who were also constructing the Crusader, came up with their own proposal for a heavy cruiser based on work originally carried out by the Birmingham Railway Carriage and Wagon Company. This was effectively an improved Crusader chassis powered by a down-rated Rolls-Royce V12 Merlin 27-litre engine, which would become known as the Meteor, driving through the Merritt-Brown gearbox already being used in the Churchill. It was an attractive combination but, at the time, there was no spare production capacity for the engine, and the decision was taken to standardise subsequent cruiser tank designs on the improved chassis of the Leyland proposal, and subsequently to adopt the 600bhp Meteor engine as soon as was practicable.

The production version of the A24 was thus a combination of the hull of the proposed A27 Cromwell married to the power train, transmission and suspension of the Crusader. This resulted in some confusion with the name. The A24 was originally named Cromwell I–similarly, the Centaur (see below) was named Cromwell II–but the decision was subsequently taken to use this name for the A27, which came later, and so it was renamed Cavalier.

Measuring 240in in length and with a width of 113in, the hull was similar to the Crusader, providing space for a five-man crew, but the levels of armour were generally improved, resulting in a combat weight of 26.5 tons. The 6-pounder (57mm) main gun was mounted in a new six-sided boxy turret and there were both coaxial and hull-mounted 7.92mm Besa machine guns. Early examples used the Mk III 6-pounder (57mm), whilst later production was fitted with the Mk V version, the latter identifiable by the barrel counterweight. Maximum speed was 24mph on the road, and 14mph across country.

A total of 500 vehicles were ordered, ‘sight unseen’, in June 1941, the first being delivered the following January. By this time, the Cavalier was being considered an interim design whilst the development of the Meteor-engined A27 Cromwell was completed.

Cruiser Tank Mk VIII (A27L)–Centaur

Designated A27L to indicate that it was fitted with the Nuffield Liberty engine, and originally named Cromwell II, the Centaur was developed in response to continued delays with the Rolls-Royce Meteor engine. It was designed by Leyland Motors under the design parentage of the Birmingham Railway Carriage and Wagon Company, with design parentage for the whole A27 series transferred to Leyland Motors in November 1941.

The hull resembled the one already used for the Cavalier, with modified Christie suspension, and consisted of bolted armour on a riveted frame; the maximum thickness of armour was 76mm, resulting in a combat weight of 28.4 tons. The Centaur was capable of a top speed of 27mph on roads, and 16mph across country and the vehicle could accommodate a crew of five. Unlike the Cavalier, which was fitted with a manual gearbox and Wilson epicyclic steering unit, the Centaur was fitted with a Merritt-Brown gearbox and steering unit, as was intended for the Cromwell. Trials showed that the engine lacked sufficient power and reliability, however, and Leyland developed an uprated Mk V version for later production examples.

In its original form, the Centaur was fitted with the 6-pounder (57mm) gun, with a coaxial 7.92mm Besa machine gun; a second Besa machine gun was often fitted in a gimbal mount at the front of the hull, and many examples carried a .303in Bren gun for anti-aircraft defence. For the later Centaur III, the 6-pounder (57mm) gun was replaced by a 75mm weapon, making it more or less equivalent to the Cromwell IV, and large numbers of Centaur Is were converted to this configuration. Centaur II was an experimental version with wider tracks, but there was no series production, whilst Centaur IV was equipped with a 95mm howitzer for the close-support role. Some 950 vehicles were constructed, eighty of them for the close-support.

In 1943, once the development work for the Meteor engine had been completed, a number of Centaurs were retrofitted with the new engine–they became known as the Cromwell X or, later, as Cromwell III. Others were converted to various other roles, including: artillery observation post, with a dummy gun fitted to the turret; anti-aircraft tank, with either an Oerlikon or Polsten gun; and ‘dozer, armoured recovery vehicle or armoured personnel carrier–in all cases, with the turret removed.

Cruiser Tank (A27M)–Cromwell

Designed by the Birmingham Railway Carriage and Wagon Company, the first pilot model for the A27M Cromwell, in mild steel, was delivered for testing in March 1942. Two more pilot machines were completed by the end of the year, followed by a further twenty for training purposes. Design parentage was passed to Leyland Motors in late 1941.

Much of the Cromwell’s success stemmed from the selection of the Rolls-Royce Meteor power unit. A down-rated but nevertheless powerful and reliable version of the famous 27-litre V12 Merlin aircraft engine, the Meteor shared some 80 per cent of its components with the Merlin, which greatly simplified production. It had been developed under the direction of Roy Robotham of Rolls-Royce specifically for use in tanks and made its first appearance during 1941 when two Crusaders, which the Cromwell was intended to replace, were experimentally fitted with the engine.

On early versions of the five-man Cromwell, the boxy hull and turret were constructed around a riveted frame onto which the armour was bolted, the large bosses on the turret providing a distinctive feature of the design. Later versions were of welded construction. The hull was 250in long and had a width of 115in; on the Cromwells VII and VIII, wider tracks pushed the width up to 120in. Like all of the A24 and A27 tanks, the suspension was of the improved Christie type with angled swinging arms suspended on long helical springs, the suspension units being fitted between the twin skins of the hull sides, giving a measure of protection from damage. There were five road wheels on each side, four of which were provided with shock absorbers.

The Meteor engine produced 600bhp from its 27 litres, and was installed in conjunction with the Merritt-Brown Z5 combined transmission and steering unit driving the rear sprockets. The engine gave the 27.5-ton tank a top speed on improved surfaces of 40mph, although this was subsequently governed to 32mph to reduce wear and tear on the running gear. The maximum speed across country was 18mph.

The A27M Cromwell and A27L Centaur variants have much in common, with several ‘marks’ of the Cromwell actually being re-engined Centaurs, in which the Liberty engine was replaced by the Meteor. The first version, the Cromwell I, was armed with a 6-pounder (57mm) main gun, together with a pair of Besa 7.92mm machine guns, one of which was coaxial to the main gun. A planned Cromwell II would have had wider tracks and lacked the hull machine gun, but none was produced. Cromwell III was a re-engined Centaur I, whilst Cromwell IV was a re-engined Centaur III, armed with a 75mm main gun capable of firing both high-explosive and anti-tank rounds–the War Office having decided to adopt the 75mm weapon as the main gun for tanks in January 1943. The Cromwell IVw was also equipped with the 75mm gun and was a converted Centaur but, as indicated by the ‘w’ suffix, had a welded hull; the Cromwell Vw was identical but was not converted from a Centaur. These were the first British tanks to be built with an all-welded hull. The Cromwell VI was a close-support variant, armed with a 95mm howitzer. Cromwell VII was an up-armoured version of either the Cromwell IV or V, fitted with wider tracks, stronger suspension and an altered final drive. Cromwell VIIw was a Cromwell Vw which had been rebuilt with the same modifications as the Cromwell VII and, finally, Cromwell VIII was a Cromwell VI rebuilt to the same standard as the Cromwell VII.

With the turret removed, the Cromwell was also used as the basis for an armoured recovery vehicle; other variants included an armoured observation post, with a dummy gun fitted, and a command vehicle. A few were also equipped with the Canadian indestructible roller device (CIRD) for exploding mines.

A total of 4,016 vehicles were constructed, and Cromwells saw their first action in June 1944 with reconnaissance regiments of the Royal Armoured Corps. The type is considered to be one of the most successful of the cruiser tanks and quickly proved to be fast, reliable and well protected. A number of Cromwells remained in service with the British Army into the post-war period.

Cruiser Tank (A30)–Challenger

The British Army’s current main battle tank is the Challenger 2 and, if those who predict the death of the main battle tank are right, it may well be the last. Despite the name, there have actually been two previous British Challenger tanks. Challenger 1 was the direct predecessor of Challenger 2, but the original Challenger actually dates back to 1942 and was effectively an up-gunned and lengthened Cromwell designed to be able to defeat the heavier armour of the German tanks.

Three pilot models were developed by the Birmingham Railway Carriage and Wagon Company by lengthening and widening the Cromwell chassis, giving a length of 320in and a width of 115in. Stothert & Pitt came up with a new cast turret to accommodate the 17-pounder (76.2mm) gun, and a coaxial .30in Browning machine gun. Mechanically, the Challenger was little changed from the Cromwell, using the Rolls-Royce Meteor engine and David Brown five-speed transmission, as well as the improved Christie suspension. There were six road wheels on either side, rather than five, but the wheels were of slightly smaller diameter.

The first of these pilot machines was delivered in August 1942, but it would be fair to say that the design was not successful. The larger hull and turret, together with the 17-pounder (76.2mm) gun, increased the weight to more than 33 tons, more than four tons heavier than the Cromwell. This proved to be too much for the suspension. At the same time, the increased width also reduced mobility. The turret was very slow to traverse and, with the standard crew of five men–now without the planned second loader–the hull was very cramped, leading to the omission of the hull machine gun. In an attempt to overcome the defects, electric traversing gear was fitted and the thickness of armour on the turret was reduced to 63mm on the front and 40mm on the sides (compared to 75mm and 60mm on the Cromwell) in order to get the weight down to 32.5 tons. The armour on the hull was unchanged, at a maximum of 101mm. The final production version had a top speed on the road of 32mph, with a cross-country maximum of around 15mph.

A total of 200, or perhaps 260, vehicles were ordered in February 1943, with the first delivered in March 1944. Although the 17-pounder (76.2mm) gun was capable of matching the performance of the German 75mm and 88mm weapons, the Challenger was never really satisfactory and production ceased in November 1943. A planned Challenger II, with a lower turret, was abandoned at the prototype stage, but the original Challenger chassis was also used to produce the Avenger self-propelled gun.

Cruiser Tank (A34)–Comet

In 1944, the British Army finally got a heavy cruiser tank that was well protected, fast and well armed. Leyland Motors had been commissioned to develop a new cruiser tank in September 1942 following the British Army’s experiences in the tank battles of the Western Desert. It had been clearly demonstrated that the British cruisers were totally outclassed by the German Panzers, particularly lacking sufficient firepower to cause any real damage to the better-armoured German machines. Leyland’s brief was to design a new heavy cruiser tank that would incorporate as many features of the A27 design as possible. To assist in this, the design parentage for the A27 series was transferred to Leyland Motors at the beginning of 1943, though considerable work was still required to remedy the inadequacies of the existing design.

Work on producing a mock-up of the A34 started in July 1943 using a modified and better-protected Cromwell hull. Production was scheduled for mid-1944 and the first prototype appeared in February of that year. Power came from the 600bhp Rolls-Royce Meteor, driving through a David Brown Z5 five-speed transmission and, with a top speed on the road of 32mph and a cross-country maximum of 16mph, the Comet was fast and reliable. It was also well protected, with a maximum thickness of 102mm of armour on the hull front, bringing the battle weight of the tank up to 35.2 tons. Both the hull and turret were of welded construction, and the hull was 301in long and 120in wide, with sufficient space to comfortably accommodate a crew of five.

A larger gun had been high on the list of desirable improvements to enable the Comet to engage the German tanks on an equal basis. The obvious candidate was the 17-pounder (76.2mm) weapon but, since there was no question of being able to widen the hull, the decision was taken to adopt the Vickers HV (high velocity) 75mm (actually 76.2mm) gun, a design which had been developed speculatively by Vickers-Armstrongs. More compact and lighter than the 17-pounder (76.2mm) from which it was derived, the gun had a shorter barrel and breech but could be reconfigured to fire similar ammunition to that used in the 17-pounder (76.2mm), using a smaller shell casing, but with almost the same armour-penetrating performance. The new gun was described as the OQF 77mm Mk II (the ‘O’ standing for Ordnance, as in Royal Ordnance) to avoid confusion with existing guns. Alongside the main gun, there was a coaxial 7.92mm Besa machine gun, with a second similar weapon in the hull.

Total production amounted to 1,186 units and, whilst it might have arrived too late to have much effect on the outcome of the Second World War, the Comet offered a sufficiently impressive performance to remain in service for a further fifteen years or so.


The first pilot model for the A9 cruiser Mk I appeared in 1936, and the first of two contracts was placed the following year. Although the A9 incorporated some of the technical advances which had been planned for the abandoned medium tank Mk III, there were initial difficulties with the brakes, the suspension, the mounting of the main gun and the auxiliary machine-gun turrets. (Warehouse Collection)


Thirty-one A10 cruiser tank Mk IIs went to France with the British Expeditionary Force (BEF) in 1940. It was not successful and the War Office criticised the machine for being slow and underpowered, with a poor cross-country performance. (Warehouse Collection)


During 1941 the A10 saw action in North Africa and in Greece, where some sixty well-worn vehicles were found to perform well against the German tanks, with most subsequently succumbing to a catalogue of mechanical failure. Surprisingly, the suspension was found to work well in the desert. (Warehouse Collection)


A total of 175 units of the A10 were constructed during 1938 and 1939, with the Mk II A replacing the original Mk II after just thirteen models had been built. (Warehouse Collection)


The cruiser tank Mk III was developed by Morris Commercial Cars and constructed by Nuffield Mechanizations and Aero. It made much of what had gone before redundant and it was the first British tank to incorporate the Christie suspension system. The photograph shows one of the two prototypes constructed during 1937 and 1938, designated A13E2 and A13E3–the original Christie tank was designated A13E1. (Warehouse Collection)


The last examples of the cruiser Mk III were delivered in the summer of 1940 and the type saw service with the 1st Armoured Division in France in 1940, as well as with the 7th Armoured Division in Libya in 1941. (Warehouse Collection)


The cruiser tank Mk IV was a logical development of the earlier Mk III, and a number of the earlier machines were subsequently up-armoured to Mk IV standard. (Warehouse Collection)


The main gun of the Mk IV was the 2-pounder (40mm), and there was also a coaxial Vickers .303in water-cooled machine gun, which on the Mk IV A was replaced by a Besa 7.92mm machine gun. (Warehouse Collection)


The cruiser tank Mk IV saw service in France in 1940, with many being abandoned at Calais, and in the desert war of 1940-41, where the relatively high speed was an asset. (Warehouse Collection)


Following their involvement with the A13 Mk II, in June 1937, the British government asked the workshops of the London Midland and Scottish Railway to assist with the design of the new A14 cruiser tank, which was to be powered by a Thornycroft marine engine, and the similar A16 (seen here), which was to be fitted with the Nuffield Liberty engine. Both were eventually abandoned in favour of the cruiser tank Mk V (A13 Mk III). (Warehouse Collection)


Although the Covenanter was used to re-equip the British 1st Armoured Division, the type never saw service outside the British Isles and was almost certainly never used in combat–although one example was destroyed by enemy action during an air raid! (Warehouse Collection)


The Covenanter was the first of a long line of British tanks to be given names beginning with ‘C’–the actual name apparently referring to a group of seventeenth-century Presbyterians who committed themselves to keeping their form of worship as the sole religion of Scotland, signing a covenant to this effect in 1638 and thus risking their lives. This example is being carried on an American White 920 18-ton tank carrier. (Tank Museum)


Lacking its 2-pounder (40mm) main gun, this Covenanter has been loaded onto the trailer of a Scammell Pioneer TRMU30/TRCU30 tank transporter. Although it remained in service throughout the war, the Pioneer tank transporter was rated at just 30 tons and was subsequently superseded by the 40-ton Diamond T Model 980/981. (Warehouse Collection)


The design work for the Crusader (A15, cruiser tank Mk VI) took place during 1938/39, and approval to construct a prototype and 200 production vehicles was given in July 1939. The pilot model was delivered in March 1940. The contract was revised in mid-1940 to 400 vehicles, and then again to 1,062. (Warehouse Collection)


There were three versions of the Crusader gun tank. The Crusader I was the original version, with a 2-pounder (40mm) gun mounted in an angular turret. Crusader II (cruiser tank Mk VIA) omitted the machine-gun turret and had additional frontal armour on the hull and turret. Crusader III (seen here) had improved hull and turret armour and was armed with a 6-pounder (57mm) weapon. (Simon Thomson)


Stowage diagram for the driver’s compartment of the Crusader I. (Warehouse Collection)


It was planned that the Crusader would be used to re-equip the British armoured divisions, and the type remained in production for four years, seeing its first action in the Western Desert in mid-1941. It was unable to match comparable German tanks in terms of armour and firepower and, although it was fast, with a maximum speed of 27mph, or better, on roads, and 15mph across country, it was never considered to be satisfactory and was frequently unreliable. The photograph shows the Crusader I with the original 2-pounder (40mm) gun. (Warehouse Collection)


Trials of the 6-pounder(57mm)-equipped Cavalier (A24, cruiser tank Mk VII) began in March 1942. The increased weight, due to a larger gun and thicker armour, meant that the tank was woefully underpowered, resulting in a short engine life and general problems with unreliability. It was almost immediately relegated to training duties and, although a few were used in northwest Europe as artillery observation posts, the type never saw active service as a gun tank. (Warehouse Collection)


Work on the design of the Centaur (A27L, cruiser tank Mk VIII) started in early 1941, and the first prototype was completed by June 1942. Here, Prime Minister Winston Churchill is shown the finer points of a Centaur III. (Warehouse Collection)


External stowage diagram for the Centaur I. (Warehouse Collection)


Although based on the Cavalier, the radiators of the Centaur were repositioned and the engine compartment layout was modified to match more closely that of the Cromwell in order to simplify the replacement of the Liberty engine with a Meteor at a later date. (Warehouse Collection)


Most Centaurs were allocated to training, but eighty or so Centaur IVs were used by the Royal Marines armoured support regiments to provide cover for British and Commonwealth forces during the opening attacks of the D-Day landings. Firing onto the shore from landing craft before being driven inland, the tanks were operated by Royal Artillery crews, with the guns manned by Royal Marines–the turret sides were distinctively marked, following the principles of naval gunnery. This example is towing a Porpoise ammunition sledge. (Warehouse Collection)


Although it was actually designed by the Birmingham Railway Carriage and Wagon Company, the A27M Cromwell–it was also described as the Cromwell III and the Cromwell M–is more generally associated with Leyland Motors who had become the design parent for the A27 series in late 1941. The photograph shows the original Cromwell I. (Warehouse Collection)


The Cromwell IV was equipped with a 75mm main gun in place of the 6-pounder (40mm) original–although it was almost a match for the later German tanks, it doesn’t seem to have helped this knocked-out unit much! (Tank Museum)


The Cromwell VI was a close-support variant, armed with a 95mm howitzer, and is the only version of the Centaur known to have seen any combat. Note how one of the crew members is leaning nonchalantly on the huge gun barrel counterweight. (Tank Museum)


The Cromwell VII was an up-armoured version of either the Cromwell IV or V, with wider tracks, stronger suspension and a final drive that reduced the maximum speed to 32mph. This example has become the victim of bitter street fighting in France. (Tank Museum)


Three pilot models for the A30 Challenger were developed by the Birmingham Railway Carriage and Wagon Company. Essentially a lengthened and widened version of the Cromwell, to which had been fitted a new cast turret to accommodate the 17-pounder (76.2mm) gun, it was designed to be able to defeat the heavier armour of the German tanks. (Warehouse Collection)


The turret of the Challenger was designed to accommodate two loaders, and included an unusual jacking feature that allowed any rounds which had jammed the unprotected turret base to be cleared. However, the turret was huge, giving the machine an overall height of 110in, compared to 98in for the Cromwell. The vehicle lacked the capacity to wade and was not used during the D-Day landings, but Challengers saw action with British reconnaissance regiments in north-west Europe in late 1944. (Warehouse Collection)


This drawing compares the A30 Challenger with the proposed A29, a 45-ton heavy cruiser that was to have been armed with the 17-pounder (76.2mm) gun. The A29 did not progress beyond the drawing board and was abandoned in favour of the A30. (Warehouse Collection)


With its high-velocity 77mm gun, the A34 Comet was fast, well armed and well protected and finally gave the British Army a tank which could take on the better-protected and better-armed German tanks–but since it did not appear until six months after D-Day, and saw no real action until the Rhine crossings in March of the following year, it could be argued that it was almost too late! (Simon Thomson)


Although the track and suspension systems were ultimately redesigned and strengthened to include conventional return rollers, the Comet was based on the hull and running gear of the A27M Cromwell. There was a new, larger cast turret and a new turret ring, designed to accommodate a new Vickers 77mm gun and, even if it was not quite up to the performance of the 17-pounder(76.2mm)-equipped Sherman Firefly, the Comet was able to engage the German tanks on an equal basis. (Warehouse Collection)


Brand-new Comet pilot vehicle, in mild steel, photographed by its makers; note the lack of track-return rollers on the original Cromwell-style suspension. (Warehouse Collection)


Some examples of the Comet survived to see service in Korea in the early 1950s, and the last British Army Comet squadron was based in Hong Kong in 1960. Surplus Comets were sold to the armies of Finland, Burma and South Africa, as well as to the Irish Defence Force. (Warehouse Collection)

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