Cruiser Tank Comet (A34)

By 1944 British cruiser tanks had finally come good with the Cromwell — fast and, thanks to its Rolls-Royce Meteor engine, reliable at last. But the Cromwell carried a fatal handicap: its 75 mm gun could not defeat the frontal armour of a Panther or a Tiger. The only British answer, the 17-pounder, had to be crammed into the Sherman Firefly’s cramped, one-man-loaded turret. British armour still lacked what it most needed — a cruiser that was fast, reliable and properly gunned in a properly designed turret.

The solution was the A34 Comet, developed by Leyland Motors as a heavily reworked Cromwell. It kept the Meteor engine and the cruiser’s speed, added better-shaped and thicker armour, and — crucially — was built around a new gun that could finally fight the German heavies on something like equal terms. It reached the troops at the very end of 1944, the last and finest British cruiser tank of the war.

The Comet’s heart was the Ordnance QF 77 mm HV. Despite the different name it fired the same lethal projectile as the 17-pounder, but in a shorter, fatter cartridge case — a deliberate compromise that gave up a little muzzle velocity in exchange for a gun compact enough to fit a roomy, well-laid-out three-man turret. It was the firepower of the Firefly without the Firefly’s ergonomic misery.

The result was a genuine tank-killer. Firing APCBC the 77 mm HV punched through roughly 110 mm of armour at 500 m, and with tungsten-cored APDS well over 150 mm — enough to defeat a Panther frontally at battle range and a Tiger from the flank or at closer range. For the first time a standard British cruiser tank could meet German armour head-on and expect to win.

Around the gun the Comet was the best-balanced tank Britain built in the war. The Rolls-Royce Meteor V12 — a detuned Merlin aero engine — gave about 600 hp and a top speed near 51 km/h, only a little down on the Cromwell despite the extra weight, and it brought the Meteor’s hard-won reliability. Armour was thicker where it counted — around 102 mm on the turret front and 76 mm on the hull front — though the plates themselves stayed flat and mostly upright: the boxy Cromwell hull carried over, not the sloped shapes of the Panther or the coming Centurion.

The improved Christie suspension, now with return rollers, gave a fast, steady ride, and the crew of five worked a turret designed for them rather than around a gun that did not fit. Weighing about 33.5 tonnes, the Comet combined speed, protection, firepower and dependability in a balance no earlier British tank had achieved.

The Comet’s one failing was timing. The first vehicles reached the veteran 11th Armoured Division in December 1944, and the division was still converting and retraining on the new tank when the Germans launched their surprise offensive in the Ardennes. Rushed back into the line, the 11th Armoured fought the Battle of the Bulge not in its new Comets but in its old Shermans and Cromwells.

Only once the winter emergency had passed could the division complete its conversion. It meant that the finest British tank of the war would get barely two months of combat before the fighting in Europe ended — a machine that had arrived, as so much good British armour did, just a little too late.

The Comet finally went to war in the spring of 1945. Its combat debut came with the great set-piece Rhine crossing — Operation Plunder — in March 1945, after which the 11th Armoured drove hard across northern Germany, reaching the Baltic at Lübeck by the war’s end. In the fast, fluid pursuit fighting of those final weeks the Comet was in its element.

Crews took to it at once. It was quick, it was mechanically dependable in a way British cruisers had rarely been, and for the first time they had a gun that let them take on a Panther without flinching. In the brief window it was given, the Comet did everything asked of it and did it well.

By common consent the Comet was the finest tank Britain fielded in the Second World War. Where earlier cruisers had forced their crews to choose between speed and a gun, or between a gun and a workable turret, the Comet delivered all of it together — the pace and reliability of the Cromwell, armour that could take a hit, and firepower that could answer the German heavies.

It was not a heavyweight brawler like the Tiger, nor was it produced in the war-winning floods of the Sherman or the T-34. But as a balanced fighting machine it was arguably the equal of any medium tank in Europe — and it pointed unmistakably at what British armour would become.

The Comet’s deepest importance lies in what came next. It was the last of the line of British cruiser tanks, and even as it entered service its successor was on the drawing board: the Centurion, which abandoned the old split between fast "cruiser" and slow "infantry" tanks in favour of a single well-armed, well-armoured universal tank. The Centurion arrived just too late for the war but became one of the most successful tanks of the 20th century.

The Comet served on for years after 1945 — with the British Army into the 1960s and, exported to nations from Finland to South Africa, in some cases into the 1980s. It stands as the bridge between the flawed British cruisers of the early war and the world-beating designs that followed: the tank that finally got it right, at the very end.

• David Fletcher, The Universal Tank: British Armour in the Second World War (HMSO).
• Peter Chamberlain & Chris Ellis, British and American Tanks of World War Two (Arms & Armour).
• David Fletcher & Richard C. Harley, Cromwell Cruiser Tank 1942–1950 (Osprey, New Vanguard) — covers Comet development.
• The Tank Museum, Bovington — Comet (A34) collection.