Churchill tank
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Tank, Infantry Mk IV Churchill VI |
|
| Tank, Infantry, Mk IV (A22) | |
|---|---|
| General characteristics | |
| Crew | 5 (commander, gunner, loader, driver, co-driver/hull gunner) |
| Length | 7.3 m (24 ft 5 in) |
| Width | 3 m (10 ft 8 in) |
| Height | 2.8 m (8 ft 2 in) |
| Weight | 38.5 tonnes |
| Armour and armament | |
| Armour | 16 to 102 mm |
| Main armament | QF 6 pdr (57 mm)
84 rounds |
| Secondary armament | 2×Besa machine guns |
| Mobility | |
| Power plant | Bedford twin-six gasoline 350 hp (261 kW) |
| Suspension | coiled spring |
| Road speed | 24 km/h (15 mph) |
| Power/weight | 9.1 hp/tonne |
| Range | 90 km |
The Tank, Infantry, Mk IV (A22) was a heavy British infantry tank of the Second World War, best known for its heavy armour and its use as the basis of many specialist vehicles. This series of tanks was named after Winston Churchill, who was not only the Prime Minister of the United Kingdom at the time, but who during the First World War had been involved with the development of the tank as a weapon.
Contents |
[edit] History
- "This tank even has more flaws than me myself!" - Winston Churchill
Initially specified prior to the outbreak of the Second World War the (A20) was to be the replacement for the Matilda II and Valentine. In accord with British Infantry Tank doctrine and based on the expected needs of World War I style trench warfare, the tank was required to be capable of navigating shell cratered ground, demolishing infantry obstacles (such as barbed wire) and attacking fixed enemy defenses; for these purposes, great speed and heavy armament was not required.
The task of design and construction of the A20 was given to Harland and Wolff, who by June of 1940 had completed four prototypes. The vehicle was armed with two 2-pounder guns each located in a side sponson and plans existed for an additional third gun in a central turret. The A20 designs were short-lived however, as at roughly the same time the emergency evacuation of the British Expeditionary Force from Dunkirk occurred. With France conquered, the scenario of trench warfare was no longer applicable and the specifications were revised by Dr. H.E. Merritt, director of Tank Design, based on the combat witnessed in Poland and France. These new specifications, the (A22), were given to Vauxhall.
With German invasion looking imminent and the United Kingdom having lost most of their military vehicles in the evacuation from France, the War Office specified that the A22 must begin production within the year. By July of 1940 the design was complete and by December of that year the first prototypes were completed; it was in June of 1941, almost exactly a year as specified, that the first Churchill tanks began rolling off the production line.
This hasty development had not come without cost though, as there had been little in the way of testing and the Churchill was plagued with mechanical faults. Most apparent was the Churchill's underpowered and unreliable engine, a situation made far worse by the engine's lack of accessibility. Another serious shortcoming of the tank was its weak armament, which was somewhat fixed by the addition of a 3 inch howitzer in the hull to deliver an HE shell albeit not on howitzer type trajectories. These flaws contributed to the tanks poor performance in its first combat outing, the disastrous Dieppe Raid in August, 1942.
The poor performance of the Churchill nearly caused production to be ceased in favour of the upcoming Cromwell tank. The Churchill was saved though by the emergence of the much improved Mk III which appeared in March, 1942 and first saw operational use during the Second Battle of El Alamein in October of that year. In the following Tunisia and Italian campaigns, the Mk III and its immediate successors continued to prove their usefulness. Among numerous mechanical fixes, the Mk III was distinct for removing the previous weapons of the Churchill and utilizing the 6 pounder gun in a new turret design.
The second major improvement in the Churchill's design, the Mk VII first saw operational use in the Battle of Normandy in 1944. The Mk VII improved on the already heavy armor of the Churchill with a wider chassis and the 75 mm gun which had been introduced on the Mk VI. It was primarily this variant, the A22F, which served through the remainder of war and was redesignated as A42 in 1945.
The Churchill was also quite notable for its versatility and was utilized in numerous specialist roles. Additionally, in tests conducted in the Madang by the Australian Army in mid-1944, at the request of the British War Office, the Churchill was tested against the M4 Sherman and found it to be, overall, a superior tank for jungle warfare.
301 of both Churchill Mk.III and Mk.IV types were delivered to the Soviet Union as part of Lend-Lease program.
The tank remained in the service of the British Army until 1952.
[edit] Design
The hull was made up of simple flat plates initially bolted but later welded together. The suspension was fitted under the two large "panniers" on either side of the hull - the track running over the top. There were eleven bogies either side, each carrying two 10-inch wheels. Only nine of the bogies were taking the vehicle weight normally, the front coming into play when the vehicle nosed into the ground or against an obstacle, the rear acting in part as a track tensioner. Due to the number of wheels, the tank could survive losing several without much in the way of adverse affects.
The twin engines were connected through a common crankshaft feeding a regenerative transmission steered by a tiller bar rather than levers or steering wheel. The Churchill was also the first tank to utilize the Merritt-Brown gear-box, which allowed the tank to be steered by changing the relative speeds of the two tracks; this effect was more pronounced as the gears were lowered, allowing the tank to fully turn on its own axis while in neutral.
The first turrets were cast with a rounded shape, sufficient for the relatively small 2 pounder gun. To fulfil its role as an infanty support vehicle the first models were equipped with a 3 inch howitzer in the hull in a layout very similar to the French Char B. This enabled the tank to deliver a useful HE round while retaining the antitank capabilities of the 2-pounder. However, like other multi-gun tanks, it was limited by a poor fire arc - the entire tank had to be turned to change the aim of the hull gun. The Mk II dispensed with the howitzer and replaced it with a bow machine gun and on the Mk III, the 2-pounder was replaced with the 6-pounder, significantly increasing the tanks anti-tank capabilities. The tank underwent field modification in North Africa with several Churchills being fitted with the 75 mm gun of destroyed M4 Shermans. These "NA75" variants were used in Italy. The use of the 75 mm, which was inferior as an anti-tank weapon to the 6-pounder but better as an all-around gun was soon made standard on successive versions. All turrets for the various Churchill's made use of the Vickers Tank Periscope MK.IV.
The armour on the Churchill, often considered its most important trait, was originally specified to a minimum of 16 mm and a maximum of 102 mm; this was increased with the Mk VII to a range from 25 mm to 152 mm. Though this armour was considerably thicker than its rivals (including the German Tiger tank) it was not sloped, reducing its effectiveness. Earlier models were given extra armour by the expedient measure of welding extra plates on.
Because the engines on the Churchill were never upgraded, the tank got increasingly slower as additional armour and armament was equipped and weight increased; while the Mk I weighed 39,118 kg and the Mk III weighed 39,626 kg, the Mk VII weighed 40,643 kg. This caused a reduction in maximum speed of the tank from its original 26 km/h down to 20.5 km/h. The engines also suffered from many mechanical problems.
Another problem was the tank's relatively small turret that prevented the usage of powerful weapons, but the 75mm gun had reasonable power. Although the thick armour could withstand several hits from any German AT gun, even some from the famous 88, the guns often lacked punch to fight back effectively. While eariler Churchills could outgun many German medium tanks, like the Panzer IV's short-barrel version and the Panzer III's 50mm gun with its 6 pdr, in late war the Churchill was armed with a 75mm gun while Germans had 75mm high-velocity cannons as their main armament.
The Churchill had many variations, including many specialised modifications. The most significant change to the Churchill was that it was upgunned from 2-pounder to 6-pounder and then 75 mm guns over the course of the war. By the war's end, the late model Churchill MK VII had exceptional amounts of armour - considerably more than the German Tiger tank. However, the firepower weakness was never fully addressed, neither all the mechanical problems.
[edit] Variants
Churchill I (303)
Equipped with a 2 pounder gun in the turret (150 rounds), and a coaxial Besa machine gun. There was a 3 inch howitzer in the hull (58 rounds). It was a tank that was noted for poor mechanical reliability. It was the main tank issued to the Canadian forces at Dieppe.
Churchill II (1,127)
Replaced the hull howitzer for another machine gun to reduce cost and complexity. Sometimes referred to as Churchill Ia.
Churchill IICS (Close Support)
Placed the gun in the hull and the howitzer in the turret, available in very limited numbers. Sometimes called Churchill II.
Churchill III (675)
The III was the first major armament overhaul of the series, eliminating the hull howitzer and equipping the tank with a more powerful 6 pounder gun (84 rounds). Unlike early versions, it had a welded turret.
Churchill IV (1,622)
The IV was the most numerous Churchill produced, and was virtually identical to the III, the largest change being a return to the less costly cast turret.
Churchill V (241)
A Churchill III / IV which was equipped with a close support 95 mm howitzer in place of the main gun (47 rounds).
Churchill VI (200)
Along with several minor improvements, it was produced as standard with the 75mm Mk V gun. Few were built due to the near release of the VII and current upgunning of the III / IV.
Churchill VII (A22F) (1,600 with XIII)
The second major redesign from previous models, the VII used the 75 mm gun, was wider and had much more armor. It is sometimes called the Heavy Churchill. This version of the Churchill first saw service in the Battle of Normandy, and was redesignated A42 in 1945.
Churchill VIII
A Churchill VII which replaced the main gun with a 95 mm howitzer (47 rounds).
Churchill IX
Churchill III / IV upgraded with turret of the VII. Extra armour added along with gearbox and suspension modifications. If the old 6 pounder (2.7 kg) had been retained, it would have the additional designation of LT ("Light Turret").
Churchill X
The same improvements as for the IX applied to a Mk VI.
Churchill XI
Churchill V with extra armour and Mk VIII turret.
Churchill Oke (3)
A Churchill II with a flamethrower. The Oke flamethrowing tank was named after its designer, Major J.M. Oke. The design was basically for a Churchill tank fitted with the Ronson flamethrowing equipment. A tank containing the flame fuel was fitted at the rear, with a pipe from it leading to the front retaining the machine gun in the hull. There were three present at Dieppe which were quickly hit, and abandoned.
Churchill NA75 (120)
Churchill III / IV with upgraded weaponry using the turret and mantlet from a destroyed or scrapped Sherman (known as NA 75 from North Africa where the conversions took place), or having their current gun rebored to 75 mm ( III* / IV (75mm) ) (84 rounds). More IV's were modified than III's, and their performance is virtually identical to the VI.
Churchill AVRE (Armoured Vehicle Royal Engineers)
A Churchill III or IV equipped with the Petard, a 290 mm Spigot mortar, throwing the 40 pound (18 kg) "Flying dustbin" with its 28 pound high explosive warhead. A weapon designed for the quick levelling of fortifications. It was designed after the Canadian failures at Dieppe and could also be equipped with numerous other attachments, such as mine flails, fascine rollers, explosive placers etc. Post WW2 the Churchill AVRE was re-armed with a breech loaded low velocity 165mm demolition gun which was less dangerous for the loader as he had had to stick his head and torso out of the Spigot Mortar armed AVRE to load the Mortar.
Churchill ARV (Armoured Recovery Vehicle)
Mk I - A turretless Mk I with a jib. Mk II - A Churchill with a fixed turret/superstructure with a dummy gun. It was equipped for recovering other tanks from the battlefield. Mounted a front jib with a 7.5 ton capacity, a rear jib rated for 15 ton and winch that could pull 25 ton. Crew was 3 with enough room for the crew of the tank being recovered. Armament was single Besa machine gun.
Churchill ARK (Armoured Ramp Karrier)
A turretless Churchill with ramps at either end and along the body to form a mobile bridge. The Mark 1 had trackways over the tracks for vehicles to drive along. The Mark 2 was an improvised version and crossing vehicles drove directly on the Churchill's tracks.
Churchill Crocodile (800)
One of the more notable Churchills, it was a Churchill VII which replaced the hull machine gun with a flamethrower. The fuel was in an armoured wheeled trailer towed behind. It could fire several 1 second bursts over 150 yards. The Crocodile was one of 'Hobart's Funnies'. A working example can still be seen at the Cobbaton Combat Collection in North Devon.
Gun Carrier, 3in, Mk I, Churchill (A22D) (50)
A fixed superstructure with the gun in a ball mount.
Churchill Flail FV3902 or Toad
A post-war (1950s) mine-clearing flail tank built on a Churchill chassis.
Churchill Goat
A chargelayer like the Double Onion device.
Churchill Kangaroo
Churchill hull converted to an APC.
 Churchill Mk I |
 Churchill Crocodile |
 A close-up of the Churchill AVRE's Petard demolition mortar |
[edit] Designs based on chassis
[edit] References
- An Illustrated Data Guide to Battle Tanks of World War II. Compiled by Christopher Chant.
[edit] External links
- Armor in Focus
- Britannica Online
- FReeper Foxhle
- Henk of Holland
- LemaireSoft
- OnWar specifications: Churchill I Churchill IV Churchill VII
- Development of the Churchill
- WWII Vehicles
- Churchills in Soviet Union
- "Churchill" Heavy Infantry Tank in the Russian Battlefield
- "Armour Welding On The Churchill Tank Mark VII" (Technical Document)
- Detailed vehicle description at 9th Battalion, Royal Tank Regiment website
- Detailed history of the 9th Battalion, using Chuchills from introduction to war's end
