- Yes
- No
Introduction and History
The Chieftain 900 was a privately funded venture from Royal Ordnance Factories (ROF), initiated in late 1981. It was an attempt to develop a modernisation package for Britain’s aging fleet of Chieftain MBTs, which were soon to be replaced with the Challenger 1. Primarily aimed at the export market, the modernisation scheme saw little to no interest, a consequence of poor relations with export customers, the generally poor international reputation of the Chieftain tank, and the advanced age of the Chieftain platform. Two prototype vehicles were completed in early 1982, and following successful automotive trials were shown for the first time at British Army Equipment Exhibition (BAEE) 1982.
The Chieftain 900 was based on a late production Chieftain chassis, with significant improvements to the 3 main properties of a tank: Protection, firepower, and mobility.
The protection upgrades are the most obvious, and they come from the generous additions of Chobham armour to the hull and turret fronts. This is the same composite armour found on the Challenger 1 MBT. The Chobham armour installed on the marketing vehicles is generally understood to only be a mock-up, so as-built it would only be acting as spaced armour, but it goes without saying that production variants of the vehicle would be fitted with the real stuff. The exact thicknesses of the proposed Chobham armour are unknown, but a reasonable estimates could be made based on the dimensions of the vehicle.
The mobility upgrades come from the Rolls Royce Condor 900E 12 Cylinder diesel engine, rated to 900hp, as well as the automatic 8-speed (6 forward 2 back) TN12-1000 Gearbox. This gearbox is also capable of regenerative steering, which may at some point be relevant to War Thunder! The engine is cooled by hydraulic fans, allowing continuous operation in temperatures of up to 52 degrees celsius.
Firepower upgrades are found in the form of L23 APFSDS, and, on the original ROF demonstrator, a range of Fire Control Systems operators for potential export customers. However, the variant being discussed in this suggestion is the Chieftain 900 with a modified turret produced by Marconi as a private venture, in the late 80s and early 90s. The Chieftain 900 was taken on by Marconi after ROF had ceased their rather unsuccessful export sales drive for the Chieftain 900. The Marconi turret features a different geometry, the Marconi Centaur FCS, as well as a roof-mounted SFIM VS 580 panoramic sight for the commander, SFIM stabilised sight for the gunner, and an SFIM/TRT Casmir Thermal Sight which feeds into both the commanders and gunners optics channels.
As part of these upgrades, unfortunately the anti-aircraft 7.62 machine gun was lost, as well as the smoke launchers, meaning this vehicle is more of a side-grade to the Chieftain 900 than a straight upgrade, but nevertheless it remains an interesting and unique Chieftain variant, among the most advanced ever built.
Specifications
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Crew: 4
Combat Weight: 56 000kg
Power to Weight Ratio: 16 hp/tonne
Ground Pressure: 0.95kg/cm3
Hull Length: 7.52m
Hull+Gun Length: 10.8m
Width: 3.51m
Height: 2.44m
Max Speed (Road): 52kph
Fording: 1.07m
Trenching: 3.15m
Engine: Rolls-Royce Conder 900E 12 Cylinder Diesel @ 900hp
Auxiliary Engine: Coventry Climax H30 3-Cylinder diesel @ 37hp
Transmission: TR12-1000 epicyclic, 6 forward 2 reverse
Steering: hydraulic operated regenerative disc steering brakes incorporated into gearbox
Armament (main): 1 x 120mm L11A5
Armament (co-axial): 1 x 7.62mm L8A2
Ammunition (main): 64 rounds, including APFS-DS, HESH, APDS, and smoke
Ammunition (auxiliary): 2000 rounds
Turret Traverse: Electric/Manual
Commander Override: Yes
Traverse Rate: 18 seconds for 360 degrees (20 degrees per second)
Max Elevation: -10, +20
Elevation Rate: 6 seconds for 30 degrees (5 degrees per second)
Gun Stabiliser: Vertical and Horizontal
Gunners Optics: SFIM VS 580 panoramic sight
Commanders Optics: SFIM stabilised sight
Thermal Optics: SFIM/TRT Casmmir Stabilised Thermal Sight
Images
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Marconi turret (left) and original Royal Ordnance Factories turret (right)
Side profile of the Marconi turret (left) and Royal Ordnance Factories turret (right)
Sources
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Official Royal Ordnance Factories Marketing Brochure (Available here)
Chieftain 900 Marketing Leaflet (Available here)
Jane’s armour and artillery 1991-1992 (Available here)
Dunstan, Simon - Chieftain Main Battle Tank 1965–2003, Osprey Publishing, 2012
Griffin, Rob - Chieftain, The Crowood Press, 2001
Taylor, Dick - Chieftain Main Battle Tank Owners Workshop Manual, J H Haynes & Co, 2016