Cruiser tank

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Cruiser tank
IWM-MH-9292-Crusader.jpg
Crusader I with auxiliary turret
Type Armoured fighting vehicle
Place of origin Britain
Service history
In service 1937–1945
Used by British Army
Wars Second World War
Specifications

Main
armament
2-Pounder gun
Secondary
armament
7.9 mm machine-gun

The cruiser tank (also called cavalry tank or fast tank) was a British tank concept of the inter-war period for tanks designed to function as modernised armoured and mechanised cavalry.

Background[edit]

Dissatisfaction with experimental medium tank designs of the mid-1930s, led to the development of specialised fast cruiser tanks where armour thickness was sacrificed for speed and infantry tanks in which speed was sacrificed for heavier armour. Financial constraints had made it impossible to produce a vehicle suitable for close support and for exploitation. The thinking was behind several tank designs which saw action during the Second World War. British armoured operations theory flowed from the decision to build two types of tank in parallel and use them to equip two types of unit and formation. Cruisers were operated by armoured regiments of the Royal Armoured Corps established on 4 April 1939 in armoured divisions, some regiments coming from the Royal Tank Regiment (RTR) and some from cavalry regiments converted during the war. Infantry tanks went to Army Tank Battalions, sometimes grouped administratively into Army Tank Brigades of the RTR. Small, fast, lightly-armed tanks like the Light Tank Mk VI operated as reconnaissance vehicles.

The use of two types of vehicle led to different theories and procedures, I tank thinking coming from the experience in the First World War from 1916–1918, when British tanks had been used for infantry support. Armoured division theory emphasised using the speed of cruiser tanks for independent action to protect flanks, attacks on an opponent's flanks and rear, pursuit and counter-attack. Giffard Le Quesne Martel originated the cruiser concept, while Assistant Director and then Deputy Director of Mechanisation at the War Office in the 1930s. He considered that medium tanks were too complicated and expensive for infantry support, where they would be too vulnerable to anti-tank weapons and rejected claims that they could fire accurately when moving, so would gain no benefit from their speed.

Martel preferred a large number of smaller and simpler tanks to swamp an opponent, instead a few comparatively expensive medium tanks. Work should continue on a universal tank in the long term but from 1936–1939, Martel gave much thought to the infantry tank and did not want medium tank development to be divided but saw the logic of it, given the constraints on tank development. Tanks were needed for mobile operations in armoured divisions and for the support of infantry when attacking fortified defensive positions; a vehicle satisfactory for both tasks appeared to be impossible and so two types were necessary.

Prelude[edit]

A damaged Cruiser Mk I CS abandoned in Calais, 1940.

Like naval cruisers, cruiser tanks were fast and mobile for operations independent from slower-moving infantry with their heavier infantry tanks and artillery. When gaps had been forced through the opponent's front by the infantry tanks, cruisers were to penetrate to the rear and attack lines of supply and communication centres in accordance with the theories of J.F.C. Fuller, Percy Hobart and B. H. Liddell-Hart. The cruiser tank was designed for use in a way similar to cavalry, which made speed the most important factor and to achieve this, early cruisers were lightly armoured and armed to save weight.

The emphasis on speed unbalanced the British designs; on limited engine power, the speed was possible only by sacrificing armour protection (by comparison infantry tanks operating at soldiers' pace could carry far more armour). The idea that "speed is armour" was considered most important in the Royal Tank Corps. It was not realised that the principle of mobility was a liability against the German policy of accepting lower speeds for superior armour and armament, ensuring that even one round from a German medium tank could easily destroy a cruiser.

Cruiser Tank Mark I (A9)

An even bigger problem for most cruiser tanks was the small calibre of their main gun. The first cruisers were armed with the QF 2-pounder (40 mm) gun. This gun had adequate armour penetration against early war tanks, but was never issued high explosive ammunition. This made the cruisers less able to deal with towed anti-tank guns. As fighting enemy tanks was part of the projected role of the cruiser tanks, they were the first to be upgraded to the heavier 6-pounder (57 mm) gun and a great deal of effort was put into developing cruiser tanks armed with the powerful 17-pounder (76 mm) gun when production began. The Cromwell had too small a turret ring for the intended high-velocity gun and was fitted with the dual-purpose medium-velocity 75 mm gun. The tank had a high-power engine giving it a maximum speed around 40 mph (64 km/h) on roads.[a]

It was the following tank design in the British cruiser line, the Comet tank with an adapted 17-pounder that entered service late in the war. As the UK had large numbers of US M4 Sherman tanks, the conversion of the Sherman to take a 17-pounder (as the Sherman Firefly) proved effective in providing more 17-pounder gun tanks. Despite the emphasis on high mobility, most cruisers were plagued by mechanical unreliability, notably the Crusader tank in the hot and gritty desert of the North Africa Campaign. This problem was usually caused by insufficient development as most of the early cruiser tank designs were ordered "off the drawing board" to bring them into service as quickly as possible and was not fully solved until the débût of the Cromwell tank in 1944, with its powerful, reliable Rolls-Royce Meteor engine.

History[edit]

Interwar[edit]

Tank production October 1938 – June 1940[1]
Year Light I tank/
Cruiser
Total
1938
4th Qtr
169 29 198
1939 734 235 969
1940
to June
140 418 558
Total 1,043 682 1,725

In 1936, the War Office decided on a light tank for the cavalry, a cruiser tank, a medium tank and an infantry or assault tank. By 1938, the medium tank had stagnated as a research project, in favour of heavier cruiser and infantry tanks and after the outbreak of war, the move towards heavy infantry tanks capable of breaking through the Siegfried Line (Westwall).[2]

In 1934, Sir John Carden of Vickers-Armstrong had produced a "Woolworth" medium tank (General Staff number A.9), to a 1934 specification for a close support tank, using elements of the Medium Mk III design (which had been abandoned due to financial reasons) but lighter and using a commercial engine, to be cheaper.[3] It was accepted as an interim design for limited production as the Cruiser Tank Mark I. It was expected to be replaced by a Christie suspension design. From 1937–1938, 125 A9s were built. The A9 was lightly armoured but capable of 25 mph (40 km/h) and carried a highly-effective QF 2-pounder (40 mm (1.6 in)) anti-tank gun.

The Cruiser Mk II (A10), was designed by Carden as an infantry tank, built to the same design with added armour for 30 mm (1.2 in) of protection. It was insufficiently armoured for the role but as a "heavy cruiser", it was put into production in July 1938 as another interim design. It had the same gun as the A9, was the first to be equipped with the Besa machine gun and 175 Mk IIs were produced by September 1940.[4] Experience with the A9 during the Battle of France in 1940, revealed shortcomings, including inadequate armour and a lack of space for the crew but it saw useful service in France, the Western desert and Greece in 1941. Orders for the Mk I and Mk II Cruisers were limited, for an advanced and faster cruiser tank which would incorporate Christie suspension designed by J. Walter Christie and have better armour.

The Cruiser Mark III (A13) with large wheels typical of the Christie suspension

In 1936, General Giffard LeQuesne Martel, a pioneer in tank design who had published works on armoured warfare and pioneered the lightly armoured "tankette" concept to enhance infantry mobility, became Assistant Director of Mechanization at the War Office. Later that year, Martel had watched Soviet tanks at the Red Army's autumn manoeuvres including the BT tank, which they had developed from Christie's work. He urged the adoption of a tank that would use the suspension system and also follow the Christie practice of using a lightweight aircraft engine such as the Liberty L-12 engine or a Napier Lion. The government authorised purchase and licensing of a Christie design via the Nuffield Organization.[5][6]

The tank A13 E1 was rudimentary and too small for British use but the Nuffield suspension was most effective and this became the basis of the Cruiser Mk III (A13). Following testing of two Nuffield-built prototypes (A13E2 and A13E3), the A13 was ordered into production and 65 were manufactured by mid-1939.[6] The Mk III weighed 31,400 pounds (14.2 t), had a crew of 4, a 340 hp engine which gave a top speed of 30 mph (48 km/h) and was armed with a 2-pounder (40 mm) gun and a machine gun. When it was introduced in 1937, the army still lacked a formal tank division.[7] The trackless element of the Christie suspension was discarded as adding little value for the extra complexity. The Cruiser Mk IV (A13 Mk II) had heavier armour than the Mk III and production started in 1938.[8]

World War II[edit]

2-pounder armed Crusader in the desert
Comet

During the early years of World War II, the Crusader was probably the best-known cruiser, it was first used in mid 1941 and used in large numbers in the Western Desert Campaign. The contemporary Covenanter was unreliable and was retained in the UK for training use. The Cavalier, Centaur and Cromwell tanks came out of the planned successor to the Covenanter and Crusader. Intended to be in production by 1942, the project was delayed and the Crusader was up-gunned as an interim measure with the Mk.III 6-pounder gun; the Cavalier was a development of Crusader. Centaur and Cromwell tanks were an alternative design using the Cavalier engine and the new Rolls-Royce Meteor respectively. The Centaur and Cromwell went into action at the Invasion of Normandy.

The Comet tank was a development of the Cromwell, using a modified 17-pounder gun and was fielded in early 1945, by then the firepower and armour protection of cruisers made them indistinguishable from medium tanks.[citation needed] During the war, the development of much more powerful engines and better suspension enabled heavier tanks to approximate the speed of cruisers with the protection of I tanks and the concept became obsolete. The Centurion tank was designed to satisfy the "Heavy Cruiser" criterion, by combining the mobility of a cruiser tank and armour of an Infantry tank in one chassis, which evolved into the "Universal tank" concept to "do it all". The Centurion transcended its cruiser tank origins and became the first modern British main battle tank.

Cruiser tanks in other armies[edit]

The cruiser-tank concept was also employed by the Soviet Union in the 1930s, as exemplified by the BT tank series (Russian: bystrokhodniy tank, "fast tank").

See also[edit]

Notes[edit]

  1. ^ By comparison the M4 Sherman had a top speed on roads about 10 mph (16 km/h) fewer; cross-country both tanks had similar maximum speeds.

References[edit]

  1. ^ Postan 1952, p. 103.
  2. ^ Postan 1964, pp. 309–310.
  3. ^ Chamberlain & Ellis 1969, p. 30.
  4. ^ Chamberlain & Ellis 1969, p. 31.
  5. ^ Harris 1995, p. 278.
  6. ^ a b Chamberlain & Ellis 1969, p. 32.
  7. ^ Steele 2005, p. 14.
  8. ^ Chamberlain & Ellis 1969, p. 33.

Bibliography[edit]

Further reading[edit]

Books

Theses

External links[edit]