The Tank Museum | E1965.16.1

FV214 Tank Heavy Gun, Conqueror Mark 1 (E1965.16.1)

FV214 Tank Heavy Gun, Conqueror Mark 1
vehicle info
Precise Name
FV214 Tank Heavy Gun, Conqueror Mark 1
Main Utility Type
Country of Use
1955, Royal Ordnance Factory, United Kingdom
Post War
location in the museum
A super-heavy design from the Fifties
Conqueror evolved as a direct response to the appearance of the Soviet IS-3 (Josef Stalin) tank and its successor, the T-10. The British War Office required a tank with a gun big enough to penetrate the Russian armour and calculated that 120mm was the minimum. Clearly any tank carrying a gun of this size would be large, but the problems of design were compounded by the need for thick armour to defeat the Russian 122mm gun in a fire fight. Conqueror started to enter service in 1955 and was issued on a limited scale to armoured regiments equipped with Centurion.

Conqueror was powered by a fuel-injected version of the Meteor engine, driving through the regular Merritt-Brown transmission. It employed a Horstmann type suspension system with resilient, steel-rimmed road wheels that made it very noisy. Its most interesting feature was the turret, a monstrous structure in cast steel which weighed 18.5 tons in its own right. The 120mm gun was an American design. It was fully stabilised for firing on the move but proved very hard work for the loader.

One of Conqueror's best features was the commander's post. This was a separate rotating cupola at the rear of the turret with its own range-finder which enabled the commander to get an accurate sight on one target while the tank was dealing with another. Conqueror remained in service until 1966 when it was replaced by Chieftain. It was the heaviest tank ever to serve with the British Army.

Gun fired separate ammunition and spent cases were automatically ejected outside vehicle.

Range finder and main armament sight in commanders turret.

Precise Name: Tank, Heavy No. 1,120mm Gun, Conqueror Mark 1

Other Name: FV214


FV214 Conqueror was the last British AFV to be officially designated as a Heavy Tank and at the time of its introduction was the heaviest tank to have served with the British Army. It was developed as a direct response to the Soviet IS III Iosif Stalin heavy tank, first seen a Soviet Victory Parade in Berlin in September 1945. The War Office view was that the thick armour and 122mm gun of the ISIII outmatched any tank in the Western armoury.

Conqueror had a lengthy development. Its’ origins lay in a 1944 project for a heavy tank, the A45. This tank was to have 6 inches (15cm) of frontal armour and was intended to support the A41 Centurion Cruiser tank in the Infantry Tank role. The War Office dropped the distinction between the Infantry and Cruiser tanks in 1946, replacing them by a single Universal tank that was capable of fulfilling all the battle field roles of the tank.

The new Universal tank, the FV200 series, was to be based on the A45. The gun tank was the FV201, fitted with an improved version of the 20 Pdr (83.4mm calibre) gun mounted in the Centurion Mk 3. After the construction of three prototypes the FV201 was cancelled in 1949 and the Centurion became the Royal Armoured Corps’ universal tank. Not only was the 20 Pdr gun incapable of penetrating the armour of the Soviet ISIII, by some oversight the FV201 was too large to fit in the Royal Navy’s standard tank landing craft.

The search for a counter to the ISIII lead to consideration of a 120mm gun based on the American T53 gun. Mounted in a new turret the L1A1/2 could be carried on a modified version of the FV201, christened the FV214. Firing Armour Piercing Discarding Sabot (APDS) rounds at 1450 metres/sec, (4,700 feet/sec), the new gun could penetrate 220 mm (8.7in) of homogeneous steel armour sloped at 30 degrees at a range of 914 metres (1,000 yards). This performance should have been sufficient to penetrate the armour of both the IS III and its successor the T10. The ammunition was separate (i.e. the round and cartridge were loaded individually) and the expended cartridge cases were automatically ejected from the turret. This gun was also fitted in the American M103 heavy tank (See E1997.152)

Clearly any tank that mounted a 120mm gun with commensurately thick armour was going to be large and heavy. However Conqueror was undoubtedly underpowered. It was propelled by an uprated version of the Rolls Royce Meteor petrol engine fitted in the Centurion, driving through a Merritt-Brown transmission. Unfortunately Conqueror weighed 15 tons more than the Centurion and mobility and agility suffered accordingly. It employed a Horstmann suspension system fitted with steel rimmed resilient road wheels that made it very noisy. Like many British tanks the Conqueror acquired a reputation for unreliability. However accounts published in ‘Tracklink’, written by men who actually crewed Conqueror, contradict this view.

Two of the tank’s most interesting features were the turret and the commander’s post. The turret was a massive cast structure that weighed 18 tons in its own right. The commander operated from a cupola mounted at the rear of the turret. This rotated independently of the turret and was fitted with its’ own range finder that enabled the commander to acquire a second target while the gunner was dealing with the first. The gun could then be quickly laid on the target found by the commander who was free to search for a third target.

Only a small number of Conquerors was made; production of the gun tank amounted to 159 vehicles, excluding the prototypes. A further 28 vehicles were built as FV219 and FV222 Armoured Recovered Vehicles, (ARV Mk 1 and Mk 2). The gun tank was manufactured in two versions: the Mark 1 and the Mark 2, the latter had minor alterations and improvements.

Conqueror started to enter service in 1955 and was issued to armoured regiments equipped with the Centurion Medium Tank. It served with the British Army of the Rhine (BAOR) and was supplanted by the Chieftain Main Battle Tank, starting in 1966.


Conqueror. Rob Griffin. The Crowood Press, 1999; ISBN 1 86126 251 5.

Summary Text by Mike Garth V1.0
Full Tracked
Gun - 120 mm Gun
Armament - Main Weapon Type
2* .30 Machine Guns Browning
Armament - Secondary Weapon Type
Rolls Royce Meteor II, M120, 12 cylinder Water cooled
Horstmann coil spring [Horstman]
5 Forward, 2 Reverse
Vehicle Statistics
Number (Crew)
Weight (Overall)
Maximum (Speed - Road)
Type (Fuel)
Radius (Range)
Maximum (Armour Thickness)
Height (Overall)
Length (Overall)
Width (Overall)
Number (Projectile)
Capacity (Fuel)
Power (Engine Output)