Great Britain's Light Tank Mark VII, A17, Purdah, PR, Tetrarch
Photos
Light Tank Mk VII, Tetrarch: |
Light Tank Mk VII, Tetrarch: |
Light Tank Mk VII, Tetrarch: |
Light Tank Mk VII, Tetrarch, with duplex drive: |
Design
Vickers created the Light Tank Mk VII as a private venture in 1937.5 The Light Tank Mk VII was adopted by the British Army in 1938.1 Production started in 1940, but was halted due to the vulnerabilities of light tanks on the battle fields of Europe.1 Production started back up in 1941 when it was decided the vehicle could be used by the airborne forces.1
Originally called the Purdah6 or PR tank it was renamed Tetrarch in 1943.1,3
The hull did not extend over the tracks. Smoke discharges on each side of the turret. Some vehicles had a spare gas tank on top of the rear deck.
Crew
There was a square box that covered the driver's head and shoulders. This could be swung open to allow the driver better visibility. No cupola for the commander and he also was the loader for the main gun.
The turret was in the center and could hold the commander and the loader.5
Suspension
The tracks were meant to be removed so that the tank could travel faster on roads. It used skid steering6 (developed by Leslie Little) which involved pivoting the wheels to make the tracks flex.1,3 The center wheels would move in or out to bow the track. It was controlled by the steering wheel. However, if the driver needed a very sharp turn then he needed to also use 2 levers and apply the brakes.1
Armament
The coaxial MG was fitted to the same mounting as the main armament and rotated and elevated with it.
Some vehicles were fitted with the Littlejohn adaptor to increase the muzzle velocity of the 2 pdr.1
Prototype
The Tetrarch's first prototype started trials in 19373,5 / 1938 and was produced by Vickers Armstrongs.1
Production
- Tetrarch Mk I: 1771,3
- Production: 1940 - 19491
Variants
- Tetrarch Mk I:
- Tetrarch Mk I CS: Had a 76.2 mm (3") howitzer installed for close support.5
- Tetrarch Mk I DD: First to have the Duplex Drive system installed.7 Had the Straussler Duplex Drive fitted, and was tested at Brent Reservoir in June 1941.1 This lead to the fitting of the Sherman with Duplex Drive.1
- Light Tanks Mk VIII Harry Hopkins: The Harry Hopkins used the Tetrarch's design.5
Usage
In 1943 they were adopted for airborne use.6 The Hamilcar glider was designed for the Tetrarch.5,6
Some were sent to Russia.1,3,5,6,7
African Continent
Used by 8th Army in Africa. Used in the invasion of Madagascar in May 1942.3,5,6,7
Flown into Normandy
One squadron of the Airborne 6th7 Armored Reconnaissance Regiment was sent in by Hamilcar glider on June 6, 1944 with 6th Airborne Division at the River Orne.1,5
Over the Rhine
Used during Rhine crossing6 on Mar. 24, 1945.5
Specifications
| Mark VII Tetrarch | Mark VII Tetrarch CS | |
|---|---|---|
| Crew | Commander, gunner, driver.2 31,2,3,4,5,6 |
|
| Physical Characteristics | ||
| Weight | 16,800 lb2,5 7.5 tons1,3,4,6 7,620 kg1,5,6 |
|
| Length w/gun | 13' 3", 13' 6"1,2,3,4,6, 14' 1.5"5 4.11 m1,6, 4.305 m5 |
|
| Length w/o gun | 13' 6"5 4.115 m5 |
|
| Height | 6' 11"1,2,3,4, 6' 11.5" 5,6 2.1 m1, 2.12 m6, 2.121 m5 |
|
| Width | 7' 7"1,2,3,4,5,6 2.31 m1,5,6 |
|
| Width over tracks | ||
| Ground clearance | ||
| Ground contact length | ||
| Ground pressure | ||
| Turret ring diameter | ||
| Armament | ||
| Main | 2 pdr QFSA2,6 2 pdr (40 mm)1,3,5 2 pdr4 |
3" howitzer2,3,4,6 76.2 mm5,6 |
| Secondary | ||
| MG | 7.92 mm Besa MG2 Besa MG4 |
|
| MG - coaxial | 7.92 mm MG5 7.92 mm Besa MG1,3,6 |
|
| Side arms | ||
| Quantity | ||
| Main | 502 |
|
| Secondary | ||
| MG | 2,0252 | |
| Side arms | ||
| Armor Thickness (mm) | 42, 142,6, 163 4 - 141 4 - 164 |
|
| Hull Front, Upper | 14 | |
| Hull Front, Lower | ||
| Hull Sides, Upper | ||
| Hull Sides, Lower | ||
| Hull Rear | ||
| Hull Top | ||
| Hull Bottom | 4 | |
| Turret Front | ||
| Turret Sides | ||
| Turret Rear | ||
| Turret Top | ||
| Engine (Make / Model) | Meadows MAT1,6 Meadows2,5 |
|
| Bore / stroke | ||
| Cooling | ||
| Cylinders | 122,5,6 | |
| Net HP | 1652,5,6 | |
| Power to weight ratio | ||
| Compression ratio | ||
| Transmission (Type) | 5 forward. | |
| Steering | Skid steering6 | |
| Steering ratio | ||
| Starter | ||
| Electrical system | ||
| Ignition | ||
| Fuel (Type) | Gasoline6 | |
| Octane | ||
| Capacity | ||
| Road consumption | ||
| Cross country consumption | ||
| Performance | ||
| Traverse | 360°2 | |
| Speed - Road | 37 mph3, 40 mph2,5,6, 39.74 mph1 64 kph1,5,6 |
|
| Speed - Cross Country | 28 mph2,5 45 kph5 |
|
| Range - Road | 140 miles2,6, 139.73 miles1 225 km1,6 |
|
| Range - Cross Country | ||
| Turning radius | ||
| Elevation limits | ||
| Fording depth | 0.914 m5 3'2,5 |
|
| Trench crossing | 1.524 m5 5'2,5 |
|
| Vertical obstacle | 1' 8" | |
| Climbing ability | ||
| Suspension (Type) | Steerable steel road wheels independently sprung.2 | |
| Wheels each side | 4 | |
| Return rollers each side | ||
| Tracks (Type) | ||
| Length | ||
| Width | 9.5"2 | |
| Diameter | ||
| Number of links | ||
| Pitch | ||
| Tire tread | ||
| Track centers/tread | 6' 6"2 |
Sources:
- The Encyclopedia of Tanks and Armored Fighting Vehicles - The Comprehensive Guide to Over 900 Armored Fighting Vehicles From 1915 to the Present Day, General Editor: Christopher F. Foss, 2002
- British and American Tanks of World War Two, The Complete Illustrated History of British, American, and Commonwealth Tanks 1933-1945, Peter Chamberlain and Chris Ellis, 1969
- World War Two Tanks, George Forty, 1995
- Tanks of the World, 1915-1945, Peter Chamberlain, Chris Ellis, 1972
- The Encyclopedia of Weapons of World War II, Chris Bishop, 1998
- The Illustrated Guide to Tanks of the World, George Forty, 2006
- Tanks of World War II, Duncan Crow, 1979
