ChieftainThe mainstay of the British Army of the 1960s and 1970s, the Chieftain mounts a long barreled 120mm cannon as well as 2 7.62mm machine guns, one coaxial and one anti-aircraft. The Chieftain solved the problem of ranging the main gun by using a ranging machine gun with similar ballistic characteristics as the cannon. When the machine gun rounds hit the target, the gunner could be reasonably assured that his cannon round will hit. The Chieftain succeeded the Centurion and was in turn replaced by the Challenger. Early Chieftains and some later modified tanks mount the 50. Cal M2HB machinegun over the main gun as a ranging gun. Iran and Kuwait retained the .50 Cal MG. The HESH round is used for antitank chemical-energy (CE) antiarmor missions, and for HE effects against personnel and materiel. The Iranians claim to employ a snorkel system on Chieftain, for fording to 5 meters depth. A variety of fire control systems and thermal sights are available for Chieftain. At 324 Chieftains have been upgraded with the Barr and Stroud TOGS thermal sight system. The 1R26 thermal camera can be used with the 1R18 thermal night sight. It has wide (13.6°) and narrow (4.75°) fields of view, and is compatible with TOGS format. GEC Sensors offers a long list of sights including: Multisensors Platform, Tank Thermal Sensor, and SS100/110 thermal night sight. Marconi, Nanoquest, and Pilkington offer day and night sights for the Chieftain. Charm Armament upgrade program, with the 120-mm L30 gun incorporated in Challenger 1, is available for Chieftain modification programs.
- Mk 5: Final production variant, with a new engine and NBC system, modified auxiliary weapons and sights. Mk 6-11 are upgrades to earlier models, with addition of IFCS. Mk 12 added ROMOR (aka: Stillbrew) spaced armor boxes. Mk 11 and Mk 12 have Thermal Observation and Gunnery Sight (TOGS).
- A variety of support vehicles were developed from the tank. They include recovery vehicles, AVLB, dozer, mineclearer, air defense and 155-mm SP artillery systems.
- Khalid/Shir 1: Jordanian variant which has chassis, turret and weaponry of the Chieftain, but which incorporates engine and running gear upgrades of Challenger I. The fire control has seen a number of improvements, including a new ballistic computer.
Alternative Designations Chieftain Mk 5 - FV 4201 Date of Introduction 1967 Original Chieftain Proliferation At least 6 countries Description Crew 4 Combat Weight (mt) 55.00 Chassis Length Overall (m) 7.48 Height Overall (m) 2.90 Width Overall (m) 3.51 Ground Pressure (kg/cm 2 ) 0.90 Automotive Performance Engine Type 750-hp Diesel Cruising Range (km) 400-500 Speed (km/h) Max Road 48 Max Off-Road INA Average Cross-Country 30 Max Swim N/A Fording Depths (m) 1.1 Unprepared Radio C42/Larkspur VHF Protection Armor, Turret Front (mm) 300 (RHA) Applique Armor (mm) ROMOR applique on turret, side skirts Explosive Reactive Armor (mm) N/A Active Protective System N/A Mineclearing Equipment Plow variant, and AVLB/engineer variant Self-Entrenching Blade No NBC Protection System Yes Smoke Equipment Smoke grenade launchers (6 each side of turret) ARMAMENT Main Armaments Caliber, Type, Name 120-mm rifled gun, L11A5 Rate of Fire (rd/min) 8-10 first minute/6 sustained Loader Type Separate-loading manual Ready/Stowed Rounds INA Elevation (°) -10 to +20 Fire on Move Yes Auxiliary Weapon Caliber, Type, Name 7.62-mm (7.62x 51) Machine gun L8A1 Mount Type Turret Coax Maximum Aimed Range (m) INA Max Effective Range (m) Day 800 Night INA Fire on Move Yes Rate of Fire INA Mount Type Cupola Maximum Aimed Range (m) INA Max Effective Range (m) Day 800 Night INA Fire on Move Yes Rate of Fire (rd/min) INA ATGM Launcher N/A FIRE CONTROL FCS Name Improved Fire Control System (IFCS) Main Gun Stabilization 2-plane Rangefinder Laser, Nd-Yag Infrared Searchlight Yes Sights w/Magnification Gunner Day Barr and Stroud Tank Laser Sight (TLS), 8x Field of View (°) 10 Acquisition Range (m) 5,000 Night 1R18 Thermal sight, 3x Field of View (°) INA Acquisition Range (m) INA Commander Fire Main Gun INA MAIN ARMAMENT AMMUNITION Caliber, Type, Name 120-mm APFSDS-T, L23A1 Maximum Aimed Range (m) 5,000 Max Effective Range (m) Day 3,000 Night INA Armor Penetration (mm) INA