Great Britain
United Kingdom of Great Britain and Ireland
Spoiler
Heavy Tanks
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Mark I
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| General | |||
|---|---|---|---|
| Name(s): | Tank, Mark I | ||
| Type: | Heavy tank | ||
| Status: | Production | ||
| Derived From: | None | ||
| Derivatives: | Mark II | ||
| Produced: | 150+1 (all models) | Production Date: | 1916 |
| Producer(s): | United Kingdom | 150+1 | 1916 |
| Metropolitan Carriage Wagon & Finance Co. | 125+1 | 1916 | |
| William Foster & Co. | 25 | 1916 | |
| Used: | 151 | Service Date: | 1916-1918 |
| User(s): | British Army | 1916-1918 |
Full User(s) List
Spoiler
| – | Unit | Date | Status |
|---|---|---|---|
| User(s): | British Army | ||
| Heavy Section, Machine Gun Corps | 01/05/1916-11/1916 | ↓Renamed↓ | |
| Heavy Branch, Machine Gun Corps | 11/1916-07/1917 | ↓Reorganized↓ | |
| Tank Corps | 07/1917-??? | ??? |
| Dimensions | |||
|---|---|---|---|
| Weight: | 28.0 t | ||
| Ground Pressure: | ??? kg/cm² | ||
| Length | Width | Height | |
| Vehicle: | 9.91 m | 4.19 m | 2.49 m |
| Ground Clearance: | ??? cm |
| Armaments | ||||
|---|---|---|---|---|
# of |
Munition (Ammo #) | Location(s), Type, Horizontal | Type, Vertical | Firing Rate |
2 x |
Q.F. Hotchkiss 6-pr. 8-cwt. Mk. II (???) | Sponsons, Mechanical, -/+52.5° @ 15°/s | Mechanical, -6°/+12° @ 4°/s | 20 rpm |
3 x |
.303-in Hotchkiss Mk. I (???) | Ballports, Manual, -/+45° @ 60°/s | Manual, -10°/+10° @ 60°/s | 450 rpm |
| Ammunition | |||
|---|---|---|---|
| Bullet | Type | Weight/Filler, Penetration @ Velocity | |
| 6-pr. 8-cwt. Gun | |||
| Q.F., 6-pr., M.D., Steel Shell, Mk. XIII | SAPHE | 2.72 kg/15 g Lyddite, 57 mm @ 554 m/s | |
| Q.F., 6-pr., M.D., Common Shell, Mk. III | HE | 2.72 kg/160 g TNT, 5 mm @ 554 m/s |
| Devices | ||
|---|---|---|
| # of - Name | Type | Effect, Location/for |
| 2 x - telescopic | Sight | 2-3.5x zoom, for 6-pr. 8-cwt. |
| Protection | ||
|---|---|---|
| Location | Thickness | Type |
| Frontwards | ||
| All front | 12 mm @ ??° | RHA |
| Sidewards | ||
| All side | 12 mm @ ??° | RHA |
| Rearwards | ||
| All rear | 12 mm @ ??° | RHA |
| Upwards | ||
| Roof | 8 mm @ ??° | RHA |
| Downwards | ||
| Floor | 6 mm @ ??° | RHA |
| Crew | |
|---|---|
| 8 | Total |
| 1 | Commander, Assistant Driver |
| 1 | Driver, Machine Gunner, Machine Gun Loader |
| 2 | Mechanics |
| 2 | Gunners |
| 2 | Gun Loaders, Machine Gunners, Machine Gun Loaders |
| Automotive | |||
|---|---|---|---|
| Fuel Capacity: | 230 l | ||
| Engine(s): | 1 x - Daimler-Knight | ||
| Type: | Gasoline | ||
| Horsepower: | 78 kW | ||
| @ RPM | 1,000 | ||
| Cylinder: | 6 | ||
| Capacity: | 13 l | ||
| Foward | Reverse | ||
| Transmission: | 3-speed | 2 | 1 |
| Steering: | Clutch-break | ||
| Brakes: | Mechanical |
| Suspension | ||
|---|---|---|
| Type: | None | |
| Road wheels: | 26 | |
| Type: | Rigid non-spaced | |
| Idlers: | Adjustable front track | |
| Return rollers: | 10 | |
| Type: | Top track | |
| Drive Sprockets: | 2 | |
| Type: | Rear drive |
| Tracks | ||
|---|---|---|
| Type: | Continuous linked steel | |
| Shoes: | ??? | |
| Length: | ??? cm | |
| Width: | ??? cm | |
| Pitch: | ??? cm | |
| Depth: | ??? cm | |
| Ground Contact: | ??? m |
| Mobility | ||
|---|---|---|
| Maximum Forward Speed: | 6.0 km/h | |
| Maximum Reverse Speed: | 1.2 km/h | |
| Power-to-Weight Ratio: | 2.8 kW/t | |
| Maximum Grade: | ???° | |
| Maximum Trench: | ??? m | |
| Maximum Wall: | ??? m | |
| Maximum Fording: | ??? cm | |
| Minimum Turning Diameter: | ??? m | |
| Cruising Range: | 38 km | |
| Mileage: | 605 l/100 km |
Summary
The Mark I was the first mass-production tank ever developed and the first to see action during the First World War. However, as with most new things, issues with it were immediately noticed when it was first deployed in combat in 1916. Namely, regarding its mobility. Due to that, all Mark I and Mark II tanks were placed in training duties the following year and for the remainder of the war, with all Mark I tanks being decommissioned by the end of the war due to the abundance of later Mark V.
Variants & Changes:
- “Mother” prototype: Identical to production versions, but was made of mild steel instead of bulletproof steel.
- Later 1916: “Mother” was refitted with a Daimler-based petrol-electric drive system, but was rejected in favor of the Wilkinson system experimented on the Mk. II. This increased the engine’s standard rpm from 1,000 to 1,400.
- Several modifications to the roof, including:
- 1916~: A net was installed atop of a few Mark Is.
- 1916~: Bar holders were installed atop of a few Mark Is in order to stow the sponson guns during transport.
- 1916~: A triangular anti-grenade mesh was installed atop of some Mark Is.
- 1917~: The steering tail was removed from all Mark Is, this decreased the length to 7.75 m.
Variant Images:
Mark II
Spoiler
| General | |||
|---|---|---|---|
| Name(s): | Tank, Mark II | ||
| Type: | Heavy tank | ||
| Status: | Production | ||
| Derived From: | Mark I | ||
| Derivatives: | Mark III | ||
| Produced: | 50 (all models) | Production Date: | 1916-1917 |
| Producer(s): | United Kingdom | 50 | 1916-1917 |
| Metropolitan Carriage Wagon & Finance Co. | 50 | 1916-1917 | |
| Used: | 50 | Service Date: | 1916-??? |
| User(s): | British Army | 1916-??? |
Full User(s) List
Spoiler
| – | Unit | Date | Status |
|---|---|---|---|
| User(s): | British Army | ||
| Heavy Branch, Machine Gun Corps | 11/1916-07/1917 | ↓Reorganized↓ | |
| Tank Corps | 07/1917-??? | ??? |
| Dimensions | |||
|---|---|---|---|
| Weight: | 28.0 t | ||
| Ground Pressure: | ??? kg/cm² | ||
| Length | Width | Height | |
| Vehicle: | 7.75 m | ??? m | 2.49 m |
| Ground Clearance: | ??? cm |
| Armaments | ||||
|---|---|---|---|---|
# of |
Munition (Ammo #) | Location(s), Type, Horizontal | Type, Vertical | Firing Rate |
2 x |
Q.F. Hotchkiss 6-pr. 8-cwt. Mk. II (???) | Sponsons, Mechanical, -/+52.5° @ 15°/s | Mechanical, -6°/+12° @ 4°/s | 20 rpm |
3 x |
.303-in Hotchkiss Mk. I (???) | Ballports, Manual, -/+45° @ 60°/s | Manual, -10°/+10° @ 60°/s | 450 rpm |
| Ammunition | |||
|---|---|---|---|
| Bullet | Type | Weight/Filler, Penetration @ Velocity | |
| 6-pr. 8-cwt. Gun | |||
| Q.F., 6-pr., M.D., Steel Shell, Mk. XIII | SAPHE | 2.72 kg/15 g Lyddite, 57 mm @ 554 m/s | |
| Q.F., 6-pr., M.D., Common Shell, Mk. III | HE | 2.72 kg/160 g TNT, 5 mm @ 554 m/s |
| Devices | ||
|---|---|---|
| # of - Name | Type | Effect, Location/for |
| 2 x - telescopic | Sight | 2-3.5x zoom, for 6-pr. 8-cwt. |
| Protection | ||
|---|---|---|
| Location | Thickness | Type |
| Frontwards | ||
| All front | 12 mm @ ??° | Mild steel |
| Sidewards | ||
| All side | 12 mm @ ??° | Mild steel |
| Rearwards | ||
| All rear | 12 mm @ ??° | Mild steel |
| Upwards | ||
| Roof | 8 mm @ ??° | Mild steel |
| Downwards | ||
| Floor | 6 mm @ ??° | Mild steel |
| Crew | |
|---|---|
| 8 | Total |
| 1 | Commander, Assistant Driver |
| 1 | Driver, Machine Gunner, Machine Gun Loader |
| 2 | Mechanics |
| 2 | Gunners |
| 2 | Gun Loaders, Machine Gunners, Machine Gun Loaders |
| Automotive | |||
|---|---|---|---|
| Fuel Capacity: | 230 l | ||
| Engine(s): | 1 x - Daimler-Knight | ||
| Type: | Gasoline | ||
| Horsepower: | 78 kW | ||
| @ RPM | 1,000 | ||
| Cylinder: | 6 | ||
| Capacity: | 13 l | ||
| Foward | Reverse | ||
| Transmission: | 3-speed | 2 | 1 |
| Steering: | Clutch-break | ||
| Brakes: | Mechanical |
| Suspension | ||
|---|---|---|
| Type: | None | |
| Road wheels: | 26 | |
| Type: | Rigid non-spaced | |
| Idlers: | Adjustable front track | |
| Return rollers: | 10 | |
| Type: | Top track | |
| Drive Sprockets: | 2 | |
| Type: | Rear drive |
| Tracks | ||
|---|---|---|
| Type: | Continuous linked steel | |
| Shoes: | ??? | |
| Length: | ??? cm | |
| Width: | ??? cm | |
| Pitch: | ??? cm | |
| Depth: | ??? cm | |
| Ground Contact: | ??? m |
| Mobility | ||
|---|---|---|
| Maximum Forward Speed: | 6.0 km/h | |
| Maximum Reverse Speed: | 1.2 km/h | |
| Power-to-Weight Ratio: | 2.8 kW/t | |
| Maximum Grade: | ???° | |
| Maximum Trench: | ??? m | |
| Maximum Wall: | ??? m | |
| Maximum Fording: | ??? cm | |
| Minimum Turning Diameter: | ??? m | |
| Cruising Range: | 38 km | |
| Mileage: | 605 l/100 km |
Summary
While work on an improved model was underway, the Mark II and III were produced as interim to keep the factories running. The Mark II differed from the early Mark I largely only superficially, with the hatches revised, the cabin narrowed, internal stowage altered, the removal of the steering tail, and the addition of a “grouser” track shoe at every sixth link in order to improve mobility. All of the tanks were made out of mild steel and were never intended to see combat, nonetheless they were deployed alongside Mark I and subsequently decimated due to their unarmored hulls being able to be penetrated by basic rifle shots. They were withdrawn from frontline service as soon as possible and served the rest of the war as training tanks.
Variants & Changes:
- 1917~: Some tanks were produced without the “grouser” track shoes.
- 03/1917: Three tanks were used as testbeds for various transmissions, including:
- Wilson Epicyclic transmission: Won the contest and was installed starting from Mark V tanks.
- Westinghouse Petrol-Electric transmission
- Wilkin’s Multiple Clutch transmission
Mark III
Spoiler
| General | |||
|---|---|---|---|
| Name(s): | Tank, Mark III | ||
| Type: | Heavy tank | ||
| Status: | Production | ||
| Derived From: | Mark II | ||
| Derivatives: | Mark IV | ||
| Produced: | 50 (all models) | Production Date: | 1917 |
| Producer(s): | United Kingdom | 50 | 1917 |
| Metropolitan Carriage Wagon & Finance Co. | 50 | 1917 | |
| Used: | 50 | Service Date: | 1917-1940 |
| User(s): | British Army | 1917-1940 |
Full User(s) List
Spoiler
| – | Unit | Date | Status |
|---|---|---|---|
| User(s): | British Army | ||
| Heavy Branch, Machine Gun Corps | 11/1916-07/1917 | ↓Reorganized↓ | |
| Tank Corps | 07/1917-18/10/1923 | ↓Reorganized↓ | |
| Royal Tank Corps | 18/10/1923-??? | ??? |
| Dimensions | |||
|---|---|---|---|
| Weight: | 28.0 t | ||
| Ground Pressure: | ??? kg/cm² | ||
| Length | Width | Height | |
| Vehicle: | 7.75 m | ??? m | 2.49 m |
| Ground Clearance: | ??? cm |
| Armaments | ||||
|---|---|---|---|---|
# of |
Munition (Ammo #) | Location(s), Type, Horizontal | Type, Vertical | Firing Rate |
2 x |
Q.F. Hotchkiss 6-pr. 8-cwt. Mk. II (???) | Sponsons, Mechanical, -/+52.5° @ 15°/s | Mechanical, -6°/+12° @ 4°/s | 20 rpm |
3 x |
.303-in Lewis Mk. I (???) | Ballports, Manual, -/+45° @ 60°/s | Manual, -10°/+10° @ 60°/s | 600 rpm |
| Ammunition | |||
|---|---|---|---|
| Bullet | Type | Weight/Filler, Penetration @ Velocity | |
| 6-pr. 8-cwt. Gun | |||
| Q.F., 6-pr., M.D., Steel Shell, Mk. XIII | SAPHE | 2.72 kg/15 g Lyddite, 57 mm @ 554 m/s | |
| Q.F., 6-pr., M.D., Common Shell, Mk. III | HE | 2.72 kg/160 g TNT, 5 mm @ 554 m/s |
| Devices | ||
|---|---|---|
| # of - Name | Type | Effect, Location/for |
| 2 x - ??? telescopic | Sight | 2-3.5x zoom, for 6-pr. 8-cwt. |
| Protection | ||
|---|---|---|
| Location | Thickness | Type |
| Frontwards | ||
| All front | 12 mm @ ??° | Mild steel |
| Sidewards | ||
| All side | 12 mm @ ??° | Mild steel |
| Rearwards | ||
| All rear | 12 mm @ ??° | Mild steel |
| Upwards | ||
| Roof | 8 mm @ ??° | Mild steel |
| Downwards | ||
| Floor | 6 mm @ ??° | Mild steel |
| Crew | |
|---|---|
| 8 | Total |
| 1 | Commander, Assistant Driver |
| 1 | Driver, Machine Gunner, Machine Gun Loader |
| 2 | Mechanics |
| 2 | Gunners |
| 2 | Gun Loaders, Machine Gunners, Machine Gun Loaders |
| Automotive | |||
|---|---|---|---|
| Fuel Capacity: | 230 l | ||
| Engine(s): | 1 x - Daimler-Knight | ||
| Type: | Gasoline | ||
| Horsepower: | 78 kW | ||
| @ RPM | 1,000 | ||
| Cylinder: | 6 | ||
| Capacity: | 13 l | ||
| Foward | Reverse | ||
| Transmission: | 3-speed | 2 | 1 |
| Steering: | Clutch-break | ||
| Brakes: | Mechanical |
| Suspension | ||
|---|---|---|
| Type: | None | |
| Road wheels: | 26 | |
| Type: | Rigid non-spaced | |
| Idlers: | Adjustable front track | |
| Return rollers: | 10 | |
| Type: | Top track | |
| Drive Sprockets: | 2 | |
| Type: | Rear drive |
| Tracks | ||
|---|---|---|
| Type: | Continuous linked steel | |
| Shoes: | ??? | |
| Length: | ??? cm | |
| Width: | ??? cm | |
| Pitch: | ??? cm | |
| Depth: | ??? cm | |
| Ground Contact: | ??? m |
| Mobility | ||
|---|---|---|
| Maximum Forward Speed: | 6.0 km/h | |
| Maximum Reverse Speed: | 1.2 km/h | |
| Power-to-Weight Ratio: | 2.8 kW/t | |
| Maximum Grade: | ???° | |
| Maximum Trench: | ??? m | |
| Maximum Wall: | ??? m | |
| Maximum Fording: | ??? cm | |
| Minimum Turning Diameter: | ??? m | |
| Cruising Range: | 38 km | |
| Mileage: | 605 l/100 km |
Summary
Like the Mark II, the Mark III was also intended to be a training tank. Unlike the Mark II, the Mark III actually only served in that capacity and remained in England for the entire duration of the war. The most significant changes from the Mark II was that the sponsons were slimmed and that all of the Hotchkiss machine guns were replaced by Lewis machine guns. At least two tanks would survive up to the Second World War, where they were then scrapped.
Variants & Changes:
None
Mark IV
Spoiler
| General | |||
|---|---|---|---|
| Name(s): | Tank, Mark IV | ||
| Type: | Heavy tank | ||
| Status: | Production | ||
| Derived From: | Mark III | ||
| Derivatives: | Mark V | ||
| Produced: | 1,220 (all models) | Production Date: | 3/1917-10/1918 |
| Producer(s): | United Kingdom | 1,220 | 3/1917-10/1918 |
| Metropolitan Carriage Wagon & Finance Co. | 820 | ??? | |
| William Foster & Co. | 100 | ??? | |
| Sir W G Armstrong Whitworth Co. Ltd. | 100 | ??? | |
| Coventry Ordnance Works Ltd. | 100 | ??? | |
| Mirlees Watson Co. | 50 | ??? | |
| William Beardmore Co. | 50 | ??? | |
| Used: | 1,220 | Service Date: | 1917-1940~ |
| User(s): | British Army | 1917-1940~ |
Full User(s) List
Spoiler
| – | Unit | Date | Status |
|---|---|---|---|
| User(s): | British Army | ||
| Heavy Branch, Machine Gun Corps | ???-07/1917 | ↓Reorganized↓ | |
| Tank Corps | 07/1917-18/10/1923 | ↓Reorganized↓ | |
| Royal Tank Corps | 18/10/1923-??? | ??? |
| Dimensions | |||
|---|---|---|---|
| Weight: | 28.0 t | ||
| Ground Pressure: | ??? kg/cm² | ||
| Length | Width | Height | |
| Vehicle: | 8.05* m | 4.12 m | 2.49 m |
| Ground Clearance: | ??? cm |
*“Tadpole tails” would increase the length to 10.79 m.
| Armaments | ||||
|---|---|---|---|---|
# of |
Munition (Ammo #) | Location(s), Type, Horizontal | Type, Vertical | Firing Rate |
| Original | ||||
2 x |
Q.F. Hotchkiss 6-pr. 6-cwt. Mk. I/II (???) | Sponsons, Mechanical, -/+52.5° @ 15°/s | Mechanical, -6°/+12° @ 4°/s | 20 rpm |
3 x |
.303-in Lewis Mk. I (???) | Ballports, Manual, -/+45° @ 60°/s | Manual, -10°/+10° @ 60°/s | 600 rpm |
| Tadpole Support | ||||
2 x |
Q.F. Hotchkiss 6-pr. 6-cwt. Mk. I/II (???) | Sponsons, Mechanical, -/+52.5° @ 15°/s | Mechanical, -6°/+12° @ 4°/s | 20 rpm |
3 x |
.303-in Lewis Mk. I (???) | Ballports, Manual, -/+45° @ 60°/s | Manual, -10°/+10° @ 60°/s | 600 rpm |
1 x |
M.L. 3-in Stokes Mk. I (???) | Rear, ???, -/+???° @ ??°/s | ???, -??°/+??° @ ??°/s | 25 rpm |
| Ammunition | |||
|---|---|---|---|
| Bullet | Type | Weight/Filler, Penetration @ Velocity | |
| Original | |||
| 6-pr. 6-cwt. Gun | |||
| Q.F., 6-pr., M.D., Steel Shell, Mk. XIII | SAPHE | 2.72 kg/15 g Lyddite, 37 mm @ 411 m/s | |
| Q.F., 6-pr., M.D., Common Shell, Mk. III | HE | 2.72 kg/160 g TNT, 5 mm @ 411 m/s | |
| Tadpole Support | |||
| 6-pr. 6-cwt. Gun | |||
| Q.F., 6-pr., M.D., Steel Shell, Mk. XIII | SAPHE | 2.72 kg/15 g Lyddite, 37 mm @ 411 m/s | |
| Q.F., 6-pr., M.D., Common Shell, Mk. III | HE | 2.72 kg/160 g TNT, 5 mm @ 411 m/s | |
| 3-in Mortar | |||
| M.L., 3-in, H.E., Mk. I | HE | 5.3 kg/1,020 g Nitrostarch or TNT, 35 mm @ 198 m/s |
| Devices | ||
|---|---|---|
| # of - Name | Type | Effect, Location/for |
| 2 x - ??? telescopic | Sight | 2-3.5x zoom, for 6-pr. 6-cwt. |
| Protection | ||
|---|---|---|
| Location | Thickness | Type |
| Frontwards | ||
| Lower frontal glacis | 16 mm @ 61° (LoS 33 mm) | RHA |
| Lowest frontal glacis | 16 mm @ 69° (LoS 45 mm) | RHA |
| Upper frontal glacis | 16 mm @ 44° (LoS 22 mm) | RHA |
| Tower front | 16 mm @ 0° | RHA |
| Sponson front | 16 mm @ 30° (LoS 18 mm) | RHA |
| Sidewards | ||
| All side | 12 mm @ 0° | RHA |
| Sponson lower side | 12 mm @ 38° (LoS 15 mm) | RHA |
| Exhaust side | 12 mm @ 34° (LoS 14 mm) | RHA |
| Rearwards | ||
| All rear | 12 mm @ 0° | RHA |
| Tower rear | 12 mm @ 34° (LoS 14 mm) | RHA |
| Sponson rear | 12 mm @ 15° (LoS 12 mm) | RHA |
| Exhaust rear | 12 mm @ 28° (LoS 14 mm) | RHA |
| Rear cover | 12 mm @ 26° (LoS 13 mm) | RHA |
| Upwards | ||
| Roof | 8 mm @ 0° | RHA |
| Front roof | 8 mm @ 82° | RHA |
| Exhaust roof | 8 mm @ 74° | RHA |
| Upper rear roof | 8 mm @ 82° | RHA |
| Lower rear roof | 12 mm @ 73° | RHA |
| Downwards | ||
| Floor | 6 mm @ 0° | RHA |
| Inwards | ||
| Inner track-sponson | 12 mm | RHA |
| Sponson stowage | 12 mm | RHA |
| Engine wall | 12 mm | RHA |
| Transmission cover | 12 mm | RHA |
| Crew | |
|---|---|
| 8 | Original |
| 1 | Commander, Assistant Driver |
| 1 | Driver, Machine Gunner, Machine Gun Loader |
| 2 | Mechanics |
| 2 | Gunners |
| 2 | Gun Loaders, Machine Gunners, Machine Gun Loaders |
| ?? | Tadpole Support |
| 1 | Commander, Assistant Driver |
| 1 | Driver, Machine Gunner, Machine Gun Loader |
| 2 | Mechanics |
| 2 | Gunners |
| 2 | Gun Loaders, Machine Gunners, Machine Gun Loaders |
| ?? | Mortar Crew |
| Automotive | |||
|---|---|---|---|
| Fuel Capacity: | 265 l | ||
| Engine(s): | 1 x - Daimler-Foster | ||
| Type: | Gasoline | ||
| Horsepower: | 78 or 93* kW | ||
| @ RPM | 1,000 or 1,250* | ||
| Cylinder: | 6 | ||
| Capacity: | 16 l | ||
| Foward | Reverse | ||
| Transmission: | 3-speed | 2 | 1 |
| Steering: | Clutch-break | ||
| Brakes: | Mechanical |
*Later Mk. IV were uprated to 93 kW @ 1,250 RPM, though most of these were modified to tank tenders afterwards.
| Suspension | ||
|---|---|---|
| Type: | None | |
| Road wheels: | 26 | |
| Type: | Rigid non-spaced | |
| Idlers: | Adjustable front track | |
| Return rollers: | 10 | |
| Type: | Top track | |
| Drive Sprockets: | 2 | |
| Type: | Rear drive |
| Tracks | ||
|---|---|---|
| Type: | Continuous linked steel | |
| Shoes: | 90 | |
| Length: | 22.23 cm | |
| Width: | 52.07 cm | |
| Pitch: | 19.05 cm | |
| Depth: | ??? cm | |
| Ground Contact: | ??? m |
| Mobility | ||
|---|---|---|
| Maximum Forward Speed: | 6.1 km/h | |
| Maximum Reverse Speed: | 1.2 km/h | |
| Power-to-Weight Ratio: | 2.8 or 3.3* kW/t | |
| Maximum Grade: | ???° | |
| Maximum Trench: | 3.5* m | |
| Maximum Wall: | ??? m | |
| Maximum Fording: | ??? cm | |
| Minimum Turning Diameter: | ??? m | |
| Cruising Range: | 56 km | |
| Mileage: | 590 l/100 km |
*Later Mk. IV were uprated to 93 kW @ 1,250 RPM, though most of these were modified to tank tenders afterwards.
*An installed “tadpole tail” increased their maximum trench to 4.25 m.
Summary
The Mark IV was the first truly mass-produced and, considered by the British Army, acceptable version of their First World War heavy tanks. It would form the largest component of the British tank force and see service from 1917 to 1918 on the frontlines of the conflict, and continue to see service up to 1940 as a training vehicle. Their first mass action was at the Battle of Cambrai where 460 Mark IV participated, proving the functionality of tanks, and three Mark IV would be a part of the first tank battle in history when they faced off against an A7V at Villers-Bretonneux. Captured examples, of at least 40 in number, would be used by Germany during the war, and after it a single Mark IV was imported to Japan.
They would serve up until at least 1940, before the last operational Mark IV, in training capacity, was damaged by a passing car.
Variants & Changes:
- 1917~: A “silencer” for their exhaust was installed on Mark IV tanks starting from early on in their production.
- 1917~: Unditching blocks were installed on the rear of tanks and positioned above the tracks. When necessary, they would be freed which would allow the tracks to carry them down and use them as additional traction against muddy ground.
- 1917-1918~: The unditching blocks were replaced by a singular unditching beam that stretched between both of the tracks once this modification became formalized.
- 1917-1918~: A single Mark IV was outfitted with Renold’s roller chains that were installed interior of the horns. These would deploy the unditching beam automatically by activating the roller chains from the interior of the tank rather than someone having to go outside to deploy it as normal from the tracks.
- 1917-1918~: The unditching blocks were replaced by a singular unditching beam that stretched between both of the tracks once this modification became formalized.
- 1917: Fascine bundles were installed on the front of tanks to assist in trench crossing during Cambrai. They weighed 30 cwt. (1,524 kg) and decreased the power-to-weight ratio from 2.8 kW/t to 2.6 kW/t.
- 1917-1918~: A single Mark IV had an Invicta mineroller installed on the front horns.
- 06/1917-10/1917: Several tanks were experimentally fitted with heavier tracks with better grip and a ramp on its front horns. It was intended to be used as a spearhead tank during the Operation Hush amphibious landings.
- 1917: In an attempt to improve their trench crossing abilities, “tadpole tails” were developed. These were installed to the rear tank horns and would increase their length to 10.79 m and their maximum trench from 3.5 m to 4.25 m, which would have been enough to overcome the larger anti-tank trenches being dug by the Germans. Despite 100 of these “tadpole tails” being made, none would be operationally used due to the introduction of the Mark V*.
- 1918~: A single “tadpole tail” Mark IV was experimentally modified to carry a 6-in. mortar in the rear between the horns.
- 1918~: The engine was uprated to 93 kW (125 hp) on later tanks which increased the power-to-weight ratio to 3.3 kW/t. However, most of these modified tanks were also converted to tank tenders due to the unreliability of the uprated engine.
- 1918: At least three tanks lengthened by means of cutting them behind the sponsons and then installing extra plating to increase the length by 6 ft, to 9.88 m. This served as the inspiration for the later Mk. V*.
Variant Images:
Spoiler
A “stock” Mark IV.
A Mark IV with an unditching beam.
*A Mark IV with Renold’s roller chains to deploy an unditching beam.
Several Mark IV with fascine bundles installed.
*A Mark IV modified with an Invicta mineroller on the front horns.
A Mark IV modified with heavier tracks and a front ramp for Operation Hush.
A Mark IV with a “tadpole tail.”
Mark V
Spoiler
| General | |||
|---|---|---|---|
| Name(s): | Tank, Mark V | ||
| Type: | Heavy tank | ||
| Status: | Production | ||
| Derived From: | Mark IV | ||
| Derivatives: | Mark V* | ||
| Produced: | 400 (all models) | Production Date: | 1917-1918 |
| Producer(s): | United Kingdom | 400 | 1917-1918 |
| Metropolitan Carriage Wagon & Finance Co. | 400 | ??? | |
| Used: | 340~ | Service Date: | 1917-1940 |
| User(s): | British Army | 1917-1940 |
Full User(s) List
Spoiler
| – | Unit | Date | Status |
|---|---|---|---|
| User(s): | British Army | ||
| Tank Corps | 1918-18/10/1923 | ↓Reorganized↓ | |
| Royal Tank Corps | 18/10/1923-??? | ??? |
| Dimensions | |||
|---|---|---|---|
| Weight: | 30.0 t | ||
| Ground Pressure: | ??? kg/cm² | ||
| Length | Width | Height | |
| Vehicle: | 8.0* m | 4.1 m | 2.64 m |
| Ground Clearance: | ??? cm |
*“Tadpole tails” would increase the length to 10.74 m.
| Armaments | ||||
|---|---|---|---|---|
# of |
Munition (Ammo #) | Location(s), Type, Horizontal | Type, Vertical | Firing Rate |
| Male | ||||
2 x |
Q.F. Hotchkiss 6-pr. 6-cwt. Mk. I/II (282) | Sponsons, Mechanical, -/+52.5° @ 15°/s | Mechanical, -6°/+12° @ 4°/s | 20 rpm |
4 x |
.303-in Hotchkiss Mk. I (6,000) | Ballports, Manual, -/+45° @ 60°/s | Manual, -10°/+10° @ 60°/s | 450 rpm |
| Hermaphrodite | ||||
1 x |
Q.F. Hotchkiss 6-pr. 6-cwt. Mk. I/II (282) | Right/Left Sponson, Mechanical, -/+52.5° @ 15°/s | Mechanical, -6°/+12° @ 4°/s | 20 rpm |
5 x |
.303-in Hotchkiss Mk. I (6,000) | Left/Right Sponsons, Mechanical, -/+52.5° @ 15°/s | Manual, -6°/+12° @ 60°/s | 450 rpm |
| Ballports, Manual, -/+45° @ 60°/s | Manual, -10°/+10° @ 60°/s | 450 rpm |
| Ammunition | |||
|---|---|---|---|
| Bullet | Type | Weight/Filler, Penetration @ Velocity | |
| 6-pr. 6-cwt. Gun | |||
| Q.F., 6-pr., M.D., Steel Shell, Mk. XIII | SAPHE | 2.72 kg/15 g Lyddite, 37 mm @ 411 m/s | |
| Q.F., 6-pr., M.D., Common Shell, Mk. III | HE | 2.72 kg/160 g TNT, 5 mm @ 411 m/s |
| Devices | ||
|---|---|---|
| # of - Name | Type | Effect, Location/for |
| 2 x - ??? telescopic | Sight | 2-3.5x zoom, for 6-pr. 6-cwt. |
| Protection | ||
|---|---|---|
| Location | Thickness | Type |
| Frontwards | ||
| Lower frontal glacis | 16 mm @ 61° (LoS 33 mm) | RHA |
| Lowest frontal glacis | 16 mm @ 69° (LoS 45 mm) | RHA |
| Upper frontal glacis | 16 mm @ 44° (LoS 22 mm) | RHA |
| Towers front | 16 mm @ 0° | RHA |
| Sponson front | 16 mm @ 30° (LoS 18 mm) | RHA |
| Sidewards | ||
| All side | 12 mm @ 0° | RHA |
| Sponson lower side | 12 mm @ 38° (LoS 15 mm) | RHA |
| Rearwards | ||
| All rear | 12 mm @ 0° | RHA |
| Tower rear | 12 mm @ 34° (LoS 14 mm) | RHA |
| Sponson rear | 12 mm @ 15° (LoS 12 mm) | RHA |
| Rear glacis | 12 mm @ 72° (LoS 39 mm) | RHA |
| Upwards | ||
| Roof | 8 mm @ 0° | RHA |
| Front roof | 8 mm @ 82° | RHA |
| Upper rear roof | 8 mm @ 82° | RHA |
| Lower rear roof | 12 mm @ 74° | RHA |
| Downwards | ||
| Floor | 6 mm @ 0° | RHA |
| Inwards | ||
| Inner track-sponson | 12 mm | RHA |
| Sponson stowage | 12 mm | RHA |
| Engine wall | 12 mm | RHA |
| Transmission cover | 12 mm | RHA |
| Crew | |
|---|---|
| 8 | Male |
| 1 | Commander, Assistant Driver |
| 1 | Driver, Machine Gunner, Machine Gun Loader |
| 1 | Mechanic, Machine Gunner, Machine Gun Loader |
| 1 | Mechanic |
| 2 | Gunners |
| 2 | Gun Loaders, Machine Gunners, Machine Gun Loaders |
| 8 | Hermaphrodite |
| 1 | Commander, Assistant Driver |
| 1 | Driver, Machine Gunner, Machine Gun Loader |
| 1 | Mechanic, Machine Gunner, Machine Gun Loader |
| 1 | Mechanic |
| 1 | Gunner |
| 1 | Gun Loader, Machine Gunner, Machine Gun Loader |
| 2 | Machine Gunners, Machine Gun Loaders |
| Automotive | |||
|---|---|---|---|
| Fuel Capacity: | 420l | ||
| Engine(s): | 1 x - Ricardo | ||
| Type: | Gasoline | ||
| Horsepower: | 110 kW | ||
| @ RPM | 1,200 | ||
| Cylinder: | 6 | ||
| Capacity: | 19 l | ||
| Foward | Reverse | ||
| Transmission: | Wilson epicyclic 4-speed | 4 | 1 |
| Steering: | Wilson epicyclic clutch-break | ||
| Brakes: | Mechanical |
| Suspension | ||
|---|---|---|
| Type: | None | |
| Road wheels: | 26 | |
| Type: | Rigid non-spaced | |
| Idlers: | Adjustable front track | |
| Return rollers: | 10 | |
| Type: | Top track | |
| Drive Sprockets: | 2 | |
| Type: | 30-tooth rear drive |
| Tracks | ||
|---|---|---|
| Type: | Continuous linked steel | |
| Shoes: | 90 | |
| Length: | 22.23 cm | |
| Width: | 52.07 cm | |
| Pitch: | 19.05 cm | |
| Depth: | ??? cm | |
| Ground Contact: | ??? m |
| Mobility | ||
|---|---|---|
| Maximum Forward Speed: | 7.7 km/h | |
| Maximum Reverse Speed: | 1.4 km/h | |
| Power-to-Weight Ratio: | 3.7 kW/t | |
| Maximum Grade: | ???° | |
| Maximum Trench: | 3.5* m | |
| Maximum Wall: | ??? m | |
| Maximum Fording: | ??? cm | |
| Minimum Turning Diameter: | ??? m | |
| Cruising Range: | 72 km | |
| Mileage: | 583 l/100 km |
*An installed “tadpole tail” increased their maximum trench to 4.25 m.
Summary
The Mark IV was the first truly mass-produced and, considered by the British Army, acceptable version of their First World War heavy tanks. It would form the largest component of the British tank force and see service from 1917 to 1918 on the frontlines of the conflict, and continue to see service up to 1940 as a training vehicle. Their first mass action was at the Battle of Cambrai where 460 Mark IV participated, proving the functionality of tanks, and three Mark IV would be a part of the first tank battle in history when they faced off against an A7V at Villers-Bretonneux. Captured examples, of at least 40 in number, would be used by Germany during the war, and after it a single Mark IV was imported to Japan.
Variants & Changes:
- 1918: Some female tanks were converted into hermaphrodites by replacing one female sponson with a male sponson. The replaced sponson could appear on either side, leading to two variations of the hermaphrodite.
- 09/1918: “Cribs” were installed on the front of tanks to assist in trench crossing during the attack on the Hindenburg Line. They weighed 12 cwt. (610 kg) and decreased the power-to-weight ratio from 3.7 kW/t to 3.6 kW/t.
- 1917: In an attempt to improve their trench crossing abilities, “tadpole tails” were developed. These were installed to the rear tank horns and would increase their length to 10.74 m and their maximum trench from 3.5 m to 4.25 m, which would have been enough to overcome the larger anti-tank trenches being dug by the Germans. Despite 100 of these “tadpole tails” being made, none would be operationally used due to the introduction of the Mark V*.
- Mark V*: See below.
Variant Images:
Spoiler
A “stock” Mark V.
Several Estonian Mark V hermaphrodites.
Several Mark V with “cribs” installed.