British heavy tanks of World War I

British heavy tanks of WWI
A British Mark I "male" tank near Thiepval on 25 September 1916, fitted with wire mesh to deflect grenades and the initial steering tail, shown raised^[1]
Type	Tank
Place of origin	United Kingdom
Service history
In service	(Mk I) from 1916
Used by	United Kingdom (Mk I–IX) German Empire (Mk IV) Empire of Japan (Mk IV) Russian Empire (White movement) (Mk V) Soviet Union (Mk V) United States (Mk V, V, VIII) France (Mk V) Canada (Mk V, V*) Estonia (Mk V) Latvia (Mk V)
Wars	First World War Russian Civil War German Revolution of 1918–19 Second World War (minimal)
Production history
Designer	William Tritton, Major Walter Gordon Wilson
Designed	1915
Manufacturer	(Mk I) William Foster & Co. of Lincoln Metropolitan Carriage, Birmingham
Produced	(Mk I) 1916
No. built	150
Variants	Mark II, Mark III, Mark IV, Mark V, Mark V, Mark V*, Mark VI, Mark VII, Mark VIII, Mark IX, Mark X, Gun Carrier Mark I
Specifications (Tank, Mark I)
Weight	Male: 28 long tons (28 t) Female: 27 long tons (27 t)
Length	32 ft 6 in (9.91 m) with tail 25 ft 5 in (7.75 m) without^[2]
Width	13 ft 9 in (4.19 m) [male] 14 ft 4 ¹⁄₂ in (4.38 m) [female]^[2]
Height	8 ft 2 in (2.49 m)^[2]
Crew	8 (commander/brakesman, driver, two gearsmen and four gunners)

Armour	0.24–0.47 in (6–12 mm)^[2]
Main armament	Male: Two Hotchkiss 6 pdr QF Female: Four .303 in Vickers machine guns
Secondary armament	Male: Three .303 in Hotchkiss Machine Guns Female: One .303 in Hotchkiss machine guns
Engine	Daimler-Knight 6-cylinder sleeve-valve 16-litre petrol engine 105 horsepower (78 kW)^[2]
Power/weight	Male: 3.7 hp/LT (2.7 kW/t) Female: 4.0 hp/LT (2.9 kW/t)^[2]
Transmission	primary gearbox: 2 forward and 1 reverse secondary:2 speeds
Suspension	26 unsprung rollers
Fuel capacity	50 imperial gallons (230 l; 60 US gal) internal^[2]
Operational range	23.6 miles (38.0 km) radius of action,^[2] 6.2 hours endurance
Speed	3.7 mph (6.0 km/h) maximum^[2]

History of the tank
Era	World War I Interwar World War II Cold War Post-Cold War
Country	Australia United Kingdom China Canada New Zealand Czechoslovakia France Germany Italy Israel Japan Poland North Korea South Korea Soviet Union Spain United States
Type	Light tank Medium tank Cruiser Tank Heavy tank Super-heavy tank Main battle tank Tank destroyer Tankette Assault gun Self-propelled gun Self-propelled anti-aircraft weapon self-propelled artillery Self-propelled mortar Multiple rocket launcher

British heavy tanks were a series of related armoured fighting vehicles developed by the UK during the First World War.

The Mark I was the world's first tank, tracked and armed armoured vehicle, to enter combat. The name "tank" was initially a code name to maintain secrecy and disguise its true purpose.^[3] The type was developed in 1915 to break the stalemate of trench warfare. It could survive the machine gun and small-arms fire in "No Man's Land", travel over difficult terrain, crush barbed wire, and cross trenches to assault fortified enemy positions with powerful armament. Tanks also carried supplies and troops.

British heavy tanks are distinguished by an unusual rhomboidal shape with a high climbing face of the track, designed to cross the wide and deep trenches prevalent on the battlefields of the Western Front. Due to the height necessary for this shape, an armed turret would have made the vehicle too tall and unstable. Instead, the main armament was arranged in sponsons at the side of the vehicle. The prototype, named "Mother", mounted a 6-pounder (57 mm) cannon and a Hotchkiss machine gun at each side. Later, subtypes were produced with machine guns only, which were designated "Female", while the original version with the protruding 6-pounder was called "Male".

The Mark I entered service in August 1916, and was first used in action on the morning of 15 September 1916 during the Battle of Flers-Courcelette, part of the Somme Offensive.^[4] With the exception of the few interim Mark II and Mark III tanks, it was followed by the largely similar Mark IV, which first saw combat in June 1917. The Mark IV was used en masse, about 460 tanks, at the Battle of Cambrai in November 1917. The Mark V, with a much improved transmission, entered service in mid-1918. More than two thousand British heavy tanks were produced. Manufacture was discontinued at the end of the war.

Development

The Mark I was a development of Little Willie, the experimental tank built for the Landships Committee by Lieutenant Walter Wilson and William Tritton between July and September 1915. It was designed by Wilson in response to problems with tracks and trench-crossing ability discovered during the development of Little Willie. A gun turret above the hull would have made the centre of gravity too high when climbing a German trench parapet (which were typically four feet high),^[5] so the tracks were arranged in a rhomboidal form around the hull and the guns were put in sponsons on the sides of the tank. The reworked design was also able to meet the Army requirement to be able to cross an 8 ft (2.4 m) wide trench.

A mockup of Wilson's idea was shown to the Landships Committee when they viewed the demonstration of Little Willie. At about this time, the Army's General Staff was persuaded to become involved and supplied representatives to the Committee. Through these contacts Army requirements for armour and armament made their way into the design. The prototype Mark I, ready in December 1915, was called "Mother" (previous names having been "The Wilson Machine", "Big Willie", and "His Majesty's Land Ship Centipede"). Mother was successfully demonstrated to the Landships Committee in early 1916; it was run around a course simulating the front including trenches, parapets, craters and barbed wire obstacles. The demonstration was repeated on 2 February before the cabinet ministers and senior members of the Army. Kitchener, the Secretary of State for War, was skeptical but the rest were impressed. Lloyd George, at the time Minister of Munitions, arranged for his Ministry to be responsible for tank production.^[6]

The Landships Committee was re-constituted as the "Tank Supply Committee" under the chairmanship of Albert Stern; Ernest Swinton, who had promoted the idea of the tank from the Army angle was also a member. General Haig sent a staff officer Hugh Elles to act as his liaison to the Supply Committee. Swinton would become the head of the new arm, and Elles the commander of the tanks in France.^[6]

The first order for tanks was placed on 12 February 1916, and a second on 21 April. Fosters built 37 (all "male"), and Metropolitan Carriage, Wagon, and Finance Company, of Birmingham, 113 (38 "male" and 75 "female"), a total of 150.^[7]

When the news of the first use of the tanks emerged, Lloyd George commented,

"Well, we must not expect too much from them but so far they have done very well, and don't you think that they reflect some credit on those responsible for them? It is really to Mr Winston Churchill that the credit is due more than to anyone else. He took up with enthusiasm the idea of making them a long time ago, and he met with many difficulties. He converted me, and at the Ministry of Munitions he went ahead and made them. The admiralty experts were invaluable, and gave the greatest possible assistance. They are, of course, experts in the matter of armour plating. Major Stern, a business man at the Ministry of Munitions had charge of the work of getting them built, and he did the task very well. Col Swinton and others also did valuable work."
— David Lloyd George^[8]

Description

The Mark I was a rhomboid vehicle with a low centre of gravity and long track length, able to negotiate broken ground and cross trenches. The main armament was carried in sponsons on the hull sides.

The hull was undivided internally; the crew shared the same space as the engine. The environment inside was extremely unpleasant; since ventilation was inadequate, the atmosphere was contaminated with poisonous carbon monoxide, fuel and oil vapours from the engine, and cordite fumes from the weapons. Temperatures inside could reach 50 °C (122 °F). Entire crews lost consciousness inside the tank or, sometimes, collapsed when again exposed to fresh air.^[9]

To counter the danger of bullet splash or fragments knocked off the inside of the hull, crews were issued with leather-and-chainmail masks.^[10] A leather helmet^[11] was also issued, to protect the head against projections inside the tank. Gas masks were standard issue as well, as they were to all soldiers at this point in the war (see Chemical warfare). The side armour of 8 mm initially made them largely immune to small arms fire, but could be penetrated by the recently developed armour-piercing K bullets. There was also the danger of being overrun by infantry and attacked with grenades. The next generation had thicker armour, making them nearly immune to the K bullets. In response, the Germans developed the 13.2 mm Mauser anti-tank rifle, and also a Geballte Ladung ("Bunched Charge") – several stick grenades bundled together for a much bigger explosion.

A direct hit by an artillery or mortar shell could cause the fuel tanks (which were placed high in the front horns of the track frames either side of the drivers' area, to allow gravity feed) to burst open. Incinerated crews were removed by special Salvage Companies, who also salvaged damaged tanks.

Steering was difficult, controlled by varying the speed of the two tracks. Four of the crew, two drivers (one of whom also acted as commander; he operated the brakes, the other the primary gearbox) and two "gearsmen" (one for the secondary gears of each track) were needed to control direction and speed, the latter never more than a walking pace. As the noise inside was deafening, the driver, after setting the primary gear box, communicated with the gearsmen with hand signals, first getting their attention by hitting the engine block with a heavy spanner. For slight turns, the driver could use the steering tail: an enormous contraption dragged behind the tank consisting of two large wheels, each of which could be blocked by pulling a steel cable causing the whole vehicle to slide in the same direction. If the engine stalled, the gearsmen would use the starting handle – a large crank between the engine and the gearbox. Many of these vehicles broke down in the heat of battle making them an easy target for German gunners. There was no wireless (radio); communication with command posts was by means of two pigeons, which had their own small exit hatch in the sponsons, or by runners. Because of the noise and vibration, early experiments had shown that radios were impractical, therefore lamps, flags, semaphore, coloured discs, and the carrier pigeons were part of the standard equipment of the various marks.^[12]

During the First World War, British propaganda made frequent use of tanks, portraying them as a wonder weapon that would quickly win the war. They were featured in films and popular songs.^[13]

Markings

The Mark IV tank Lodestar III at the Belgian Royal Museum of the Army, Brussels (2005). This tank retains its original paint

When first deployed, British tanks were painted with a four-colour camouflage scheme devised by the artist Solomon Joseph Solomon. It was found that they quickly got covered with mud, rendering elaborate, camouflage paint schemes superfluous. In late 1916, the Solomon scheme was abandoned and tanks were painted with a single shade of dark brown.^[14]

At the rear of the tank, a three, four or five digit serial number was painted in white or yellow at the factory. At the front there was a large tactical marking, a prefix letter indicating the company or battalion, and a number (training tanks had no letter, but three numbers).^[15] Some tanks had their tactical number painted on the roof for air recognition.^[16] Later, vertical red and white stripes were painted on the front to aid recognition after the Germans began deploying captured British tanks.

Tanks were often given individual names and these were sometimes painted on the outside. A small handful were known to carry artwork (similar to aircraft nose art).^[15]

Variants

The first tanks were known as the Mark I after the subsequent designs were introduced. Mark I's that were armed with two 6 pounder guns and three .303 Hotchkiss machine guns were called "Male" tanks; those with four Vickers machine guns and one Hotchkiss, were called "Female". Ernest Swinton is credited with inventing the terms.^[17]

To aid steering, a pair of large wheels were added behind the tank. These were not as effective as hoped and were subsequently dropped.

The subsequent Mark II, III, IV, and V, and later tanks, all bear a strong resemblance to Mother.

Mark I

British Mark I tank with the Solomon camouflage scheme

Crew: 8
Combat Weight
- Male: 28 tons (28.4 tonnes)
- Female: 27 tons (27.4 tonnes)
Armour: 0.23–0.47 in (6–12 mm)
Armament
- Male: two 6-pounder QF, three Hotchkiss Machine Guns
- Female: four 0.303 in Vickers Machine Guns, one Hotchkiss Machine Gun

The Gun Carrier Mark I was a separate design, intended to carry a field gun or howitzer that could be fired from the vehicle. In service, it was mostly used for carrying supplies and ammunition. Forty-eight of them were built.

Initial production of the Mark I was to be by Fosters and Metropolitan: 25 from Fosters and 75 from Metropolitan, which had greater capacity in Wednesbury at the Old Park site of the Patent Shaft Company, a subsidiary of the Metropolitan.^[18] Metropolitan also received an order for a further 50 so that the Army would be able to raise six tank companies of 25 tanks each and set up further production under their Oldbury Wagon and Carriage Company. As there were not enough 6-pounder guns available for all 150 tanks, it was decided to equip half of them with just machine guns. A new sponson design with two Vickers machine guns in rotating shields was produced.^[19]

Mark II

Mark II; tank no. 799 captured near Arras on 11 April 1917

The Mark II incorporated minor improvements over the Mark I. With the Army declaring the Mark I still insufficiently developed for use, the Mark II (for which orders were first placed in July) would continue to be built, but would be used only for training.^[17] Due to this intended role, they were supposedly clad in unhardened steel, though some doubt was cast on this claim in early 1917.^[20] Initially, 20 were shipped to France and 25 remained at the training ground at Wool, Dorset in Britain; the remaining five were kept for use as test vehicles. As the promised Mark IV tanks had not arrived by early 1917, it was decided, despite the protestations of Stern (see below), to ship the 25 training vehicles in Britain to France,^[20] where they joined the other 20 Mark IIs and 15 Mark Is at the Battle of Arras in April 1917. The Germans were able to pierce the armour of both the Mark I and Mark II tanks at Arras with their armour-piercing machine gun ammunition.

The Mark II was built from December 1916 to January 1917 by Foster & Co and Metropolitan (25 Male and 25 Female respectively).^[21]

Five Mark IIs were taken for experiments on improved powerplants and transmission. They were provided to firms to show what improvements they could make over the Mark I system in an open competition. In the demonstrations held in March 1917, only three of them were able to compete alongside Mother, which had been fitted with a Daimler petrol-electric system. Wilson's epicyclic gear system, which replaced the secondary gear and the gearsmen, was clearly superior and adopted in later designs.

Surviving parts from Mark II no. 799 (D26), including tracks and gunshields, can be seen at the Musée Jean et Denise Letaille, Bullecourt.

Mark III

The Mark III was a training tank and used Lewis machine guns and a smaller sponson for the females. Fifty were built. It was originally intended that the Mark III was to have all the proposed new design features of the Mark IV. This is why there were two distinct training types, the Mark II being little more than a slightly improved Mark I. However, development of the new features was so slow that the change from the Mark II was very gradual. The last two Mark IIIs were melted down in the Second World War. They did not see action overseas.

Mark IV

A female Mark IV tank C14. Photographed with German forces after the Battle of Cambrai. December 1917

Mark IV female tank knocked out

The Mark IV was a more heavily armoured version of the Mark I, and went into production in May 1917. Fundamental mechanical improvements had originally been intended, but had to be postponed. The main change was the introduction of shorter-barrelled 6-pounder guns. It had all its fuel stored in a single external tank (located between the rear track horns) in an attempt to improve crew safety. The sponsons could be pushed in to reduce the width of the tank for rail transportation. Rails on the roof carried an unditching beam. A total of 1,220 were built: 420 males, 595 females and 205 tank tenders, which were supply tanks.

The Mark IVs were used successfully at the Messines Ridge in June 1917, where they outpaced the infantry on dry ground, but in the Third Ypres of July and August they found the swampy ground difficult and were of little use. About 432 Mark IV tanks were used during the Battle of Cambrai in November 1917.

The first tank-to-tank battle was between Mk IV tanks and German A7Vs in the Second Battle of Villers-Bretonneux in April 1918.^{[lower-alpha 1]}

Mark V series

Mark V "male" tank, showing short 6-pounder (57-mm) Hotchkiss gun in right sponson

The Mark V was first intended to be a completely new design of tank, of which a wooden mock-up had been finished. However, when the new engine and transmission originally destined for the Mark IV became available in December 1917, the first, more advanced Mark V design was abandoned for fear of disrupting the production run. The designation "Mark V" was switched to an improved version of the Mark IV, equipped with the new systems. The original design of the Mark IV was to be a large improvement on the Mark III but had been scaled back to be a mild improvement because of technical delays. The Mark V thus turned out very similar to the original design of the Mark IV – i.e. a greatly modified Mark III.

Four hundred were built, two hundred each of Males and Females. Several were converted to Hermaphrodites (also known as "Composites") by fitting one male and one female sponson so that each tank had a 6-pounder. This measure was intended to ensure that female tanks would not be outgunned when faced with captured British male tanks in German use or the Germans' own A7V.

The Mark V was first used in the Battle of Hamel on 4 July 1918, when 60 tanks contributed to a successful assault on the German lines by Australian units. It took part in eight further major engagements during the War. A number saw service in the Allied intervention in the Russian Civil War on the White Russian side. Most were captured and used by the Red Army in the Russian Civil War. Four were retained by Estonian forces, and two by Latvia.

Mark V*

The Mark V* was a version with a stretched hull, lengthening it by six feet. It had a larger "turret" on the roof and doors in the side of the hull. The extra section was also designed to house a squad of infantry. The weight was 33 tons. Of orders for 500 Males and 200 Females, 579 had been built by the Armistice – the order was completed by Metropolitan Carriage in March 1919.^[22]

A British Mark V* tank—on the roof, the tank carries an unditching beam on rails, that could be attached to the tracks and used to extricate itself from difficult muddy trenches and shell craters

Mark V**

A British Mark V** tank

Because the Mark V* had been lengthened, its original length-width ratio had been spoiled. Lateral forces in a turn now became unacceptably high, causing thrown tracks and an enormous turn circle. Therefore, Major Wilson redesigned the track in May 1918, with a stronger curve to the lower run reducing ground contact and the tracks widened to 26.5 in (673 mm). The Mark V engine was bored out to give 225 hp (168 kW) and sited further back in the hull. The cabin for the driver was combined with the commander's cabin; there now was a separate machine gun position in the back. Of a revised order for 700 tanks (150 Females and 550 Males), only 25 were built and only one of those by the end of 1918.^[22]

Mark VI

The Mark VI was one of a pair of related projects to develop the tank initiated in late 1916. The Mark V would be the application of as many advanced features as could be managed on the Mark I hull design and the Mark VI would be a complete break with the Mark I hull. The Mark V would not be built as such, because of the delays with the Mark IV and it would be a different Mark V that was built. The Mark VI project design had a completely new hull – taller and with rounded track paths. The single main gun was in the front of the hull. It did not progress past the stage of a wooden mock-up; the project was cancelled in December 1917 in order that a tank co-developed with the US (the Mark VIII) could go forward.

Mark VII

Mark Knothe, the Technical Liaison Officer between Stern, Elles and Anley, contributed to the development of the tank, designing a longer Mark I with Williams-Janney hydraulic transmission;^[23] one of the Mark IIs used as test vehicles had used a hydraulic transmission. In October 1917 Brown Brothers^{[lower-alpha 2]} in Edinburgh were granted a contract to develop this line of research further. In July 1918, the prototype was ready. Its drive system was very complex. The 150 hp (112 kW) Ricardo engine drove into Variable Speed Gear Ltd. pumps that in turn powered two hydraulic motors, moving one track each by means of several chains. To ward off the obvious danger of overheating, there were many fans, louvres and radiators. However, steering was easy and gradual and the version was taken into production to equip one tank battalion. Three had been built, and only one delivered out of an order for 74 when war ended.^[23] It was passed over in favour over the VIII, which was ordered at the same time. The hull was slightly lengthened in comparison with the Mark V. No Mark VIIs survive.

Mark VIII

The Allied Mark VIII (Liberty) tank

When Stern was removed from his post following disagreements with the War Office, he was sidelined by appointment to a new department to work on a cooperative design between the Allies – assembly in France, hulls, guns and their ammunition from the UK and other components (principally the engines) from the USA.^[24] American involvement in the development of the tank design led to the Mark VIII, also known as "Liberty" or Anglo-American tank (though initially the French were partially involved).

The engine was compartmentalised from the crew, and the turret structure included forward and rear firing machine guns. Of a planned (shared production) of 1,500 each, a single British prototype was finished by the end of the war. The British built just 24, the Americans completed 100 between September 1918 and 1920, at the Rock Island Arsenal, at a cost of $35,000 [£8,750] apiece ($430,000 [£226,000] in 2006). About 40 hulls for the U.S Liberty were produced by the Manchester Tank Syndicate, 11 British Type Mark VIII by the North British Locomotive Co.^[25]

They were used and upgraded until the 1930s, when they were given to Canada for training; some M1917s were sold to the Canadians at nominal scrap value. The tank itself was over 34 feet (10 m) long, and there had been an even longer 44 foot (13 m) version planned but never made (the Mark VIII*). The tank was outdated by the 1930s due to its speed (under 6 mph/10 km/h) and armour (16–6 mm), but it did have one of the longest independent trench crossing capabilities of any armoured fighting vehicle (AFV) ever made. Modern main battle tanks and AFVs rely on bridge laying tanks for crossing large deep trenches.

Crew: 12 (later 10)
Weight 37 tons (37.6 tonnes)
Length/Height/Width : 34 ft 2 in by 10 ft 3 in by 12 ft 4 in (10.4 m by 3.1 m by 3.8 m) (Mark VIII* length 44 ft/13.4 m)
Engine: Ricardo 330 hp petrol (UK), Liberty V12 300 hp (U.S.).^[25]

Mark IX

The Mark IX was a troop carrier or infantry supply vehicle – among the first tracked armoured personnel carrier not counting experiments with the lengthened Mk Vs. Thirty-four were built out of an order for 200.

Mark X

The Mark X was a paper-only project to improve the Mark V, originally known as Mark V***. This was basically a contingency plan in case the Mark VIII project would fail (if so a production of 2000 was foreseen for 1919), trying to produce a tank with as many parts of the Mark V as possible but with improved manoeuvrability and crew comfort.

Combat history

Disabled British Mark I female tank at the Second Battle of Gaza

A disabled Mark IV tank near Cambrai, 1917

German forces using captured British Mark IVs during the Second Battle of the Marne

The first tanks were added, as a "Heavy Branch", to the Machine Gun Corps until a separate Tank Corps was formed on 28 July 1917 by Royal Warrant. A small number of Mark I tanks took part in the Battle of the Somme during the Battle of Flers-Courcelette in September 1916. They were used to cut through barbed wire to clear the way for infantry, and were even driven through houses to destroy machine gunner's emplacements.^[26] Although many broke down or became stuck, almost a third that attacked made it across no man's land, and their effect on the enemy was noted, leading to a request by the British C-in-C Douglas Haig for a thousand more. This came as a surprise: William Tritton had already started the development of a heavier tank: the Flying Elephant. Unfortunately for the Allies, it also gave the Germans time to develop a specifically designed anti-tank weapon for the infantry, an armour-piercing 7.92 mm K bullet.

Eight Mk I tanks were used against Turkish forces in the Second Battle of Gaza in April 1917 during the Sinai and Palestine Campaign. With its three destroyed tanks replaced by Mk IVs, the tank company fought at the Third Battle of Gaza.

British tanks were used with varying success in the offensives of 1917 on the Western Front; however, their first large scale use in a combined operation was at the Battle of Cambrai in November 1917, when nearly 400 tanks working closely with advancing infantry and a creeping barrage overran the German lines in the initial attack. During the Battle of Amiens in August 1918, several hundred Mark V tanks, along with the new Whippet and Mk V* tanks, penetrated the German lines in a foretaste of modern armoured warfare.

Mark V tanks captured by the Red Army from the White Army in the course of the Russian Civil War were used in 1921 during the Red Army invasion of Georgia and contributed to the Soviet victory in the battle for Tbilisi.^[27]

In 1945, occupying troops came across two badly damaged Mk V tanks in Berlin. Photographic evidence indicates that these were survivors of the Russian Civil War and had previously been displayed as a monument in Smolensk, Russia, before being brought to Berlin after the German invasion of the Soviet Union in 1941.^[28] Accounts of their active involvement in the Battle of Berlin have not been verified.^[29]

Surviving vehicles

A number of tanks survive, although several are just shells that have had all internal components removed. The largest collection is at The Tank Museum at Bovington in the United Kingdom, which holds eight tanks. Two of these are maintained in running condition, the Mark IV Male, Excellent and Mark V Male number 9199. Excellent last ran in the 1980s and 9199 in the 2000s. The Bovington museum does not intend to run them again, due to the wear and tear that would be inflicted on the now-fragile, historic vehicles.^[30] Instead, the museum acquired a replica Mark IV tank (constructed for the film War Horse), which is used for public demonstrations.

Little Willie

Little Willie survives at the Bovington Tank Museum. It was saved from being scrapped in 1940 on the pretext that it was helping to defend Bovington base against possible German attacks. Many other prototypes were melted down during the invasion scare.