|Opening Salvo: Churchill Crocodile|
|by Michael J. Canavan, Sr|
Command Sergeant Major
US Army (retired)
The Churchill was the replacement for the Matilda II. Design work began in 1939 by Harland & Wolff with assistance from Woolwich. The original design was modeled after early WW I tanks, such as the Mark IV tank used at the Battle of Cambrai. This design had side sponsons mounting 2-pounder guns. Four prototypes, designated the A20, were built, but they were judged to be underpowered.
Vauxhall took over the contract for the next infantry tank, the A22. Using the A20 as a starting point, Vauxhall was given one year to design, test, and build the tank with the stipulation that production lines would be assembling the tank within 12 months. The first pilot model was up and running within 7 months. A total of 5,460 Churchill tanks were produced.
A22 Churchill Infantry Tank
The Churchill was powered by twin, in-line, Bedford 6 cylinder engines which developed 350 horsepower. The Vauxhall-Bedford engine was designed and developed in just 89 days. The tank weighed about 40 tons (depending upon version) and had a top speed of 24 km/hour with a range of about 140 km.
A few close support Churchills were built with a second 3-inch howitzer replacing the 2-pounder gun in the turret, but the design never saw full production. The Chuchill II and later versions replaced the hull gun with a 7.92mm BESA machine gun. In March 1942, the turret gun was replaced with a 6-pounder gun and the model named the Churchill III. Further improvements resulted in the Mark VII having a 75 mm gun and the Mark VIII being equipped with a 95 mm close support howitzer. Some Mark IVs in North Africa were modified to accommodate a 75mm gun and a Browning .30 cal machine gun in the turret.
The interior layout of the tank allowed the Churchill to carry plenty of ammunition. The Mark I carried 150 rounds of 2 inch and 58 rounds of 3 inch howitzer ammo and along with a crew of five. The hull was wide enough that the Mark III could carry a 6-pounder turret, although the 75 mm and 95 mm weapons on other versions left less interior room.
The Mark VII was the first British tank to have all-round vision in the commander’s cupola when closed down, even though it was common in German tanks. The Churchill was also the first British tank to be equipped with Merrit-Brown regenerative steering, which saved power when turning, allowed sharper turns, and allowed the driver to turn the tank on its own axis while in neutral. Hydraulic steering and brake controls made driving the tank less tiring and allowed the driver finer judgment in the use of the controls. The suspension consisted of 11 bogey wheels on each side, which resulted in a bumpy ride. On the plus side, they were cheap, simple, and relatively easy to replace. Further, the suspension could still support the tank and keep it moving even with some bogies significantly damaged, removed, or destroyed completely.
The tight time constraints during design resulted in many small flaws in early Churchills. The engines were not easily accessible and the fuel pump, driven by a flexible shaft beneath the engines, had a tendency to snap, immobilizing the vehicle. Engine tappets broke frequently, requiring the engine to be replaced. The carburetors were easily jarred out of adjustment, causing a loss in power and fuel efficiency. The power-to-weight ratio was low, making the tank sluggish. While these problems were eventually ironed out, they stung the Churchill with a reputation for fragility and unreliability that it never lived down.
There were many variants of the Churchill. The chassis was adapted for use as a bridge layer, mine clearer, armored recovery vehicle, and flamethrower. It was particularly successful as an Armored Vehicle Royal Engineers (AVRE). One of the more famous variants was the Crocodile, in which a flame projector replaced the machine gun on the right of the glacis to supplement the main gun and coaxial machine gun. It carried 400 gallons of fuel and nitrogen propellant for the flame projector in a towed, armored trailer. The fuel/nitrogen mix was fed into the tank via an articulated coupling at the rear between the tank and trailer. The Crocodile could fire about 80 one-second bursts of flame at a range of 90 to 120 yards.
In Northern Europe, the Crocodile and AVRE made a formidable team. The AVRE first destroyed heavy fortifications by firing a 44-pound demolition charge up to 80 meters. The Crocodile then turned its flamethrower on the resulting wreckage. Often, simply projecting un-ignited fuel into a wrecked bunker was enough to persuade survivors to surrender.
The Churchill saw action primarily in Europe and North Africa. A few Mk IIIs were tried at Alamein and thereafter were used in increasing numbers in Tunisia and Italy. Several brigades of Chuchills were deployed to northwest Europe. The Churchill remained in service well into the 1950s.