Chieftain tank
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| Chieftain (FV4201) | |
|---|---|
 Chieftain Mk 10 or Mk 11 with Stillbrew Crew Protection Package. |
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| Type | Main Battle Tank |
| Place of origin | United Kingdom |
| Service history | |
| Used by | UK, Iran, Kuwait, Oman |
| Wars | Iran-Iraq War,Iraq-Kuwait War |
| Production history | |
| Manufacturer | Leyland |
| Specifications | |
| Weight | 55 t |
| Length | 7.5 m (hull) |
| Width | 3.5 m |
| Height | 2.9 m |
| Crew | 4 |
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| Armour | Glacis: 120 mm (72º) Hull sides: 38 mm (10º) Turret: 195 mm (60º) |
| Primary armament |
120 mm rifled (L11A5) |
| Secondary armament |
2 x L7 MG |
| Engine | Leyland L60 (diesel) 750 hp (560 kW) |
| Suspension | Horstmann |
| Operational range |
500 km (road) |
| Speed | 48 km/h (road) 30 km/h (off-road) |
The FV 4201 Chieftain was the main battle tank of the United Kingdom during the 1960s and 1970s. It was one of the most advanced tanks of its time, having the most powerful main gun and armour of any tank in the world until the late 1970s.[citation needed] The Chieftain also introduced a supine (lying backwards) driver position, enabling a heavily sloped and reduced height hull.
Contents |
[edit] Overview
The Chieftain was a radical evolutionary development of the successful Centurion line of tanks that had emerged near the end of the Second World War. The British had learned during the war that their tanks often lacked sufficient protection and firepower compared to those fielded by the enemy, and that this had led to high casualty levels when faced with the superior German tanks in World War II.
Leyland, who had been involved in Centurion, had built their own prototypes of a new tank design in 1956, and these led to a War Office specification for a new tank. The design was accepted in the early 1960s. Chieftain was designed to be as well protected as possible and to be equipped with a powerful 120 mm rifled cannon. The heavy armour came at the price of reduced mobility, chiefly due to engine power limitations, which was perhaps the Chieftain's main drawback. The engine selected took the multi-fuel route and as introduced gave less than the planned output; improvements to the engine did not increase power to the desired value.
[edit] Design
The Chieftain design included a heavily sloped hull and turret. It had a mantleless turret, in order to take full advantage of reclining the vehicle up to ten degrees in a hull-down position. The driver lay semi-recumbent in the hull when his hatch was closed down which helped to reduce overall height. To the left side of the turret was a large infra-red searchlight in an armoured housing. The suspension was of the Horstmann bogie type, with large sideplates to protect the tracks and provide stand-off protection from hollow charge attack.
The engine is a two-stroke opposed piston design intended for multi-fuel use so it could run on petrol or diesel or anything in between. In practice the engine did not deliver the expected power, and was unreliable but improvements were introduced to address this. Primary problems included, cylinder liner failure, fan drive problems and perpetual leaks due to vibration and badly routed pipework. However, as the engine power improved the tank itself became heavier. The tank was steered by conventional tillers hydraulically actuating onto external brake discs. The discs worked via the epicyclic gearbox providing 'regenerative' steering. In reality the discs and pads became soaked in oil and diesel and the steering became difficult. The gearbox was operated motorcycle-style with a kick up/kick down "peg" on the left which actuated electro-hydraulic units in the gearbox.The accelerator is cable operated by the right foot. In the turret the loader was on the left and the gunner on the right of the gun with the commander behind the gunner.
The main 120 mm gun was innovative, as it burnt away the cartridge, leaving nothing to be discarded. Other tank guns had to store the spent shell cartridge or eject them outside. It was said that the tank was built around this gun[who?].
Israel was involved in early development of the Chieftain. Cancellation of this collaboration by Britain was one of the reasons for Israeli indigenous development of the Merkava MBT.
[edit] Service
Like its European competitors, the Chieftain found a large export market in the Middle East, but unlike the earlier Centurion, it was not adopted by any other NATO or Commonwealth countries.
The Chieftain proved itself capable in combat and able to be upgraded with enhancements both for overall improvement and to meet local requirements. The Chieftain tanks were continuously upgraded until the early 1990s when they were replaced by the Challenger series of tanks whose design was influenced by that of Chieftain. The final Chieftain version used by the British Army until 1995, incorporated "Stillbrew" armour named after Colonel Still and John Brewer from the Military Vehicles and Engineering Establishment (MVEE), the Improved Fire Control System (IFCS) and the Thermal Observation Gunnery Sight (TOGS).
The first Chieftain model was introduced in 1967. Chieftains were supplied to at least six countries, including Iran, Kuwait, Oman and Jordan. An agreement for sale of Chieftains to Israel was cancelled by the British Government in 1969 [1]. The largest foreign sale was to Iran, which took delivery of around 1,000 "Mk5(P)" before the 1979 revolution. Further planned deliveries of the more capable 4030 series were cancelled at that point. The tank's main combat experience was in the Iran-Iraq war of 1980-88.
[edit] Specifications
- Crew: 4
- Combat Weight: 55 tons
- Overall Length: 10.8 m (gun forward)
- Hull Length: 7.5 m
- Height: 2.9 m
- Width: 3.5 m
- Powerplant: Leyland L60 (diesel) 750 hp
- Range: 500km
- Max Road Speed: 48 km/h
- Cross-Country Speed: 30 km/h
- Armour: turret front, 195 mm RHA (60°)
[edit] Armament
- 120 mm L11A5 rifled tank gun
- Rate of fire: 8 rounds per minute
- Elevation: -10 to +20 degree
- Laser rangefinder
- Coaxial L8A1 7.62 mm machine gun
- Cupola-mounted L37A1 7.62mm machine gun
Mark 1 and Mark 2 models had coaxial .50 cal. ranging machine guns prior to the introduction of the laser rangefinder.
[edit] Equipment
- Twin Clansman VRC 353 VHF Radio sets
- 1 C42 1 B47 Larkspur VHF radios
- 2 X 6-barrel smoke dischargers on turret
- Bulldozer blade (optional - fitted to one tank per squadron)
[edit] Variants
- Chieftain Mk 1
- 40 training vehicles for 1965/1966.
- Chieftain Mk 2
- First service model with 650 hp engine.
- Chieftain Mk 3
- Extra equipment fitted giving rise to several submarks.
- Chieftain Mk.5
- Final production variant, with upgrades to the powerplant and NBC protection system.
- Chieftain Mk.6-9
- Incremental upgrades to earlier Marks of tanks, including addition of Clansman radios.
- Chieftain Mk.10
- Mark 9 upgrade, addition of Stillbrew Crew Protection Package to the turret front and turret ring.
- Chieftain Mk.11
- Mark 10 upgrade, searchlight replaced with the Thermal Observation and Gunnery System (TOGS), manufactured by Barr and Stroud.
- Chieftain Mk.12/13
- Proposed further upgrades, cancelled when the Challenger 2 was introduced.
- FV4205 AVLB
- Bridge-laying vehicle.
- FV4204 ARV/ARRV
- Armoured Recovery Vehicle, Armoured Recovery and Repair Vehicle.
- Chieftain Marksman
- SPAAG version, equipped with the Marksman turret.
- Chieftain Mineclearer
- Mine-clearing development.
- Chieftain Sabre
- Twin 30 mm AA turret.
- Khalid (also designated 4030P2J - P = Phase & J = Jordan)/Shir 1
- Jordanian / Iranian variant with running gear of the Challenger 1. Basically this was a transition vehicle from the Chieftain to the Shir2 which had been intended for Iran but was subsequently cancelled. The Shir2 tanks became Challenger1 tanks after reworking at ROF Leeds. The vehicle chassis comprised the front half of a Chieftain Hull and the rear of a 4030/2 Chassis. This allowed the fitment in the engine bay of a Rolls CV8 engine.
- Weapon Carriers
- The Chieftain chassis was modified to mount air defense weapons ("Marksman" 2 x 35 mm cannon) and a 155mm howitzer in various modifications.
- Shir 2
- Iranian variant. Visible external differences from the Chieftain Mk5 included a sloping rear hull, Removal of the Searchlight from the left turret area and storage baskets refitted, water channel removed from around drivers hatch on the glacis plate, modified light clusters also on the glacis plate, Larger sight housing on commanders cupola.
[edit] Operators
British Army - used from 1965 to 1995
Iran - 1,000 Chieftain Mark 5(P) obtained before the 1979 revolution. Further planned deliveries of the more capable 4,030 series were canceled at that point. 100 as of 2005. (100 in 1990, 250 in 1995, 140 in 2000, 200 in 2002)
Iraq - 30 in service with Iraqi Regular Army in 1990. All destroyed or scrapped.
Israel - An agreement for sale of Chieftains to Israel was canceled by the British Government in 1969.
Jordan - ?
Kuwait - ?
Oman - ?
[edit] References
[edit] External links
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