the army still lacked a formal tank division. 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. Second World War The Tank, Cruiser, Mk VI, (Crusader), was 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 were the planned successors 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 three vehicles were similar in appearance. Orders for the Cavalier were cut back while the similarity between Centaur and Cromwell meant some Centaurs were finished as Cromwells. The Cavalier was used for training while Centaur and Cromwell tanks went into action at the Invasion of Normandy. The Comet tank entered service in north-west Europe in 1945 but neither the Cromwell or Comet tanks were in sufficient numbers to replace American tanks in the British Army. During the war, the development of much more powerful engines and better suspension enabled cruiser tanks to increase in size, armour and firepower while retaining their speed and mobility. With "cruiser" tanks similarly armoured to heavier, slower, infantry tanks, the convergence of cruisers and infantry tank designs made the distinction obsolete. The Centurion tank was designed as a heavy cruiser, by combining the mobility of a cruiser tank and armour of an Infantry tank. The Centurion transcended its cruiser tank origins and became the first modern British main battle tank. Cruiser tanks in other armies In the 1930s, the Czechoslovak Army divided its tank into three categories, light tanks - cavalry, light tanks - infantry and medium tanks. The cavalry category was analogical to cruiser-tank concept. The cruiser-tank concept was also employed by Canada, and Soviet Union in the 1930s, as exemplified by the BT tank series (, [fast tank]). See also History of the tank Tanks of the interwar period Tanks in World War II Comparison of early World War II tanks Tanks in the Cold War Post-Cold War Tanks