Mark I tank

Mark I Tank
A British Mark I "male" tank near Thiepval on 26 September 1916, fitted with wire mesh to deflect grenades and the initial steering tail, shown raised. Photo by Ernest Brooks
Type	Tank
Place of origin	United Kingdom
Service history
In service	1916–1931, and 1945(briefly)
Used by	United Kingdom Germany Soviet Union United States France Canada Australia Estonia Latvia
Wars	World War I, Russian Civil War, World War II
Production history
Designer	William Tritton, Major Walter Gordon Wilson
Designed	1915
Manufacturer	William Foster & Co. of Lincoln Metropolitan Carriage, Birmingham
Produced	1915–1919
Number built	150
Variants	Mark II, Mark III, Mark IV, Mark V series, Mark VI, Mark VII, Mark VIII, Mark IX, Mark X, Gun Carrier Mark I
Specifications
Weight	Male: 28 tons (28.4 tonnes) Female: 27.4 tonnes
Length	32 ft 6 in (9.94 m) with tail
Width	13 ft 9 in (4.33 m) [male]
Height	8 ft 0.5 in (2.44 m)
Crew	8 (commander, driver, two gearsmen and four gunners)

Armour	0.23–0.47 in (6–12 mm)
Primary armament	Male: Two 6 pdr QF or 6 pdr 6 cwt QF Female: Four .303 Vickers machine guns
Secondary armament	Male: Four .303 in Hotchkiss Machine Guns Female: Two .303 in Hotchkiss machine guns
Engine	Daimler-Knight 6 cylinder sleeve valve petrol engine 105 hp
Power/weight	Male: 3.7 hp/tonne Female: 3.8 hp/tonne
Transmission	primary gearbox:2 forward and 1 reverse secondary:2 speeds
Operational range	6.2 hours endurance
Speed	4 miles per hour maximum

The British Mark I was a tracked vehicle developed by the British Army during World War I and the world's first combat tank, entering service in August 1916, and first used in action on the morning of 15 September 1916.^[1] Born of the need to break the domination of trenches and machine guns over the battlefields of the Western Front, it was the first vehicle to be named "tank", as an expedient to maintain secrecy and to disguise its true purpose.^[2] It was developed to be able to cross trenches, resist small-arms fire, travel over difficult terrain, carry supplies, and be able to capture fortified enemy positions. It is regarded as successful in many respects, but suffered from many problems due to its primitive nature.

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 in the summer of 1915. Working on problems discovered with Willie, the Mark I was designed by Wilson. A gun turret above the hull would have made the centre of gravity too high, so the guns were put in sponsons. The prototype Mark I, ready in December 1915, was called "Mother", (previous names having been "The Wilson Machine", "Big Willie", and "HMLS Centipede"). One hundred and fifty of the Mark I were built.

Description

The Mark I was a rhomboid vehicle with a low centre of gravity and long track length, able to grip muddy ground and cross trenches. Sponsons (also called "barbettes") on the hull sides carried two naval 6-pounder guns. There were two Hotchkiss machine guns in the sponsons and two removable guns for the front and back.

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

To counter the fumes inside and the danger of bullet splash or fragments and rivets knocked off the inside of the hull, the crew wore helmets with goggles and chainmail masks. 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 regular stick grenades bundled together for a much bigger explosion.

A direct hit on the roof 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. They were forbidden to speak about this aspect of their work with still living tank crews.^[3]

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 who were encouraged to complete their suicidal mission by receiving bottles of strong drink, carried by the tanks, as a reward. Because of the noise and vibration, early experiments had shown that radios were impractical, so lamps, flags, semaphore, coloured discs, and the carrier pigeons were part of the standard equipment of the various marks.^[4]

Variants

A requirement was found for two types of armament, so Mark Is were armed either with 6 pounder guns and four machine guns and called "Male" (75) or two Vickers machine guns instead of the 6 pounders and called "Female" (75). Swinton is credited with inventing the terms.^[5]

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 their "Mother".

Mark I

Crew: 8
Combat Weight
- Male: 28 tons (28.4 tonne)
- Female: 27 tons (27.4 tonne)
Armour: .23-.47 in (6-12 mm)
Armament
- Male: two 6-pounder QF, four 8 mm Hotchkiss Machine Guns
- Female: two .303 Vickers Machine Guns, four 8 mm Hotchkiss Machine Guns

The Gun Carrier Mark I was largely produced with parts identical to those used to build the Mark I.

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 order^[6] would continue to be built but it would be used for training only.^[7] Almost all were built of unhardened steel, but among those at the training ground at Wool, Dorset some (25) were found to have hardened steel^[8] and these were shipped to France, despite the protestations of Stern (see below), and used in the Battle of Arras in April 1917 because of delays in the production of the Mark I tank.

The Mark II was built from December 1916 to January 1917 by Foster & Co and Metropolitan (25 Male and 25 Female respectively).^[9]

Mark III

The Mark III was a training tank, which used Lewis machine guns and a smaller sponson for the females. Fifty were built. It was originally intended that the Mark III 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. Development of the new features was so slow however, that the change from the Mark II was very gradual. The last two Mark III's were melted down in World War II.

Mark IV

Mark IV was an up-armoured version of the Mark I which went into production in May 1917. Fundamental mechanical improvements had originally been intended but these had to be postponed, the main change consisting in the switch to shorter-barrelled 6-pounder guns. It had all 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.

Mark V series

Mark V
A British Mark V (Male) tank
Service history
In service	1918 -
Production history
Designer	Major Wilson
Designed	1917
Manufacturer	Metropolitan Carriage
Produced	1917- June 1918
Number built	400
Specifications
Weight	Male: 29 tons Female: 28 tons
Length	26 ft 5 in (8.5 m)
Width	Male: 13 ft 6 inch (4.19 m) Female: 10 ft 6 in
Height	2.64 m (8 ft 8 in)^[10]
Crew	8 (commander, driver, two gearsmen and four gunners)

Armour	14 mm (0.55 in) maximum
Primary armament	Male: Two 6 pdr 6 cwt QF with 207 rounds Female: Four .303 Vickers machine guns
Secondary armament	Male: Four .303 in Hotchkiss Mk 1 Machine Gun Female: Two .303 in Hotchkiss machine guns
Engine	19 litre six cylinder in-line Ricardo petrol engine 150 hp (110 kW)
Power/weight	Male: 5.2 hp/ton
Transmission	4 forward 1 reverse, Wilson epicyclic in final drive
Fuel capacity	100 imperial gallons (450 l)
Operational range	45 mi (72 km) about 10 hours endurance
Speed	5 mph (8.0 km/h) maximum
Steering system	Wilson epicyclic steering

The Mark V was first intended to be a completely new design of tank. When however in December 1917 the desired new engine and transmission became available, this design was abandoned and the designation switched to an improved version of the Mark IV, in fact a Mark IV as it was originally intended. The Mark V had more power (150 bhp) from a new Ricardo engine. Use of Wilson's epicyclic steering gear meant that only a single driver was needed. On the roof towards the back of the tank behind the engine was a second raised cabin for a machine-gunner and the tank commander. The machine guns now fired through ball mounts rather than loopholes giving better protection and wider field of fire.

Four hundred were built, 200 each of Males and Females. Several were converted to Hermaphrodites by swapping sponsons to give a single 6 pounder gun for each. These are also sometimes known as "Mark V Composite".

The Mark V was a late participant in the First World War. It was first used in the Battle of Hamel on 4 July 1918 when 60 tanks contributed to a successful assault by Australian units on the German lines. A number saw service in the Allied intervention in the Russian Civil War on the White Russian side. They participated in the British North Russia Campaign. Some saw service with the Estonian forces after Russian forces had to retreat into Estonia and be disarmed and were used until 1941. Mark Vs were also delivered to the French, Canadian and American armies.

A Mark V tank can be seen in several photographs taken in Berlin in 1945 in front of the Berliner Dom (Berlin Cathedral). It has been suggested this was a museum piece that had been previously displayed at the Lustgarten and it had been used as a static pillbox to help bolster the city's defences during Nazi Germany's final days. However, there is no evidence this was the case and it is not clear what role (if any) it played in the Battle of Berlin.

Mark V*

In 1917 Sir William Tritton developed the Tadpole Tail: an extension of the tracks to be fitted to the back of a tank to improve trench crossing abilities. This was necessary because the Hindenburg Line had 3.5 m (3.8 yd) wide trenches to stop the British tanks. When Major Philip Johnson of the Central Tank Corps Workshops heard of this project, he immediately understood that the weight of the heavy girders strengthening the attachment might be put to a better use by creating a larger tank. He cut a Mark IV in half and stretched the hull, lengthening it by six feet. When details had been forgotten, it was for a long time assumed that most Mark V* had been field conversions made by Johnson. It is now known that they were all factory-built. It had a larger "turret" on the roof and doors in the side of the hull. 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.^[9]

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

The extra section was also designed to house a squad of infantry. This was the first ever purpose designed tracked armoured personnel carrier (APC), it was also the first APC to be significantly armed, as some earlier conversions of tanks into supply carriers lacked any armament. It could operate as a tank as well as carrying troops, and it was not until the post World War II era Merkava that a tank that could also carry troops under protection was produced.

Note: the asterisk (*) in early British tank designations was usually pronounced as "star" when spoken, e.g., Mark Five-star, or Mark Five-star-star, etc.

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 (but increasing ground pressure as a trade-off) and the tracks widened to 26.5 inches. The Mark V engine was bored out to give 225 hp 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.^[9]

Mark V***

See: Mark X.

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;^[11] one of the Mark IIs used as test vehicles had used a hydraulic transmission. In October 1917 Brown Brothers ^[12] 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 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. Steering was easy and gradual however 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.^[11] It was passed over in favour over the V** 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^[13] 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, 24 were built by the British before they pulled out of the project and 100 completed by the Americans. The 100 were produced between September 1918–1920, 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..^[14]

They were used and upgraded until the 1930s when given to Canada for training (as opposed to the M1917s which were sold at 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.).^[14]

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 V's. 34 were built out of an order for 200.

Mark X

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

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.^[15] Although many broke down or became stuck, almost a third that attacked made it across no mans 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 bit of 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 bullet.

During the Battle of Amiens in August 1918, several hundred Mark V tanks with the new Whippet tanks penetrated the German lines in a foretaste of modern armoured warfare.

Even in the end of WWII in Europe, at least two Mk V tank leftovers were used by German garrison in defense of Berlin. It's unknown whom the tanks were captured from. Both tanks were destroyed in the subsequent battle in Berlin. ^[16]

Surviving vehicles

Little Willie

Little Willie survives at the Bovington Tank Museum; it was saved from being scrapped in 1940—many other prototypes were melted down during the Invasion Scare—on the pretext it was helping to defend Bovington base against possible German attacks.