A20 heavy tank

A20 was a British tank design by Harland and Wolff to meet an Army requirement for an infantry tank that could replace the Matilda II and Valentine tank. It was designed in the expectation that conditions would be similar to those of the First World War.

A20
Type	Infantry tank
Production history
Designer	Mechanisation Board
Designed	1939
Manufacturer	Harland and Wolff
No. built	4
Specifications
Crew	7
Armour	maximum of 80 mm
Main armament	2-pdr in turret 2-pdr in hull
Secondary armament	machine guns
Maximum speed	15 mph

The specification was produced by Superintendent of Tank Design at Woolwich with design by the Mechanization Board and passed to Harland and Wolff for detail work and to build a pilot. Four pilots were ordered in February 1940, the first pilot took part in trials in June 1940.[1]

The Battle of France indicated that trench warfare was not going to be the case in WWII. A new specification, A22, was drawn up and Vauxhall Motors who had been engaged to find a suitable power plant - their Bedford twin six engine - for the A20 were instructed to bring a tank based on the A20 into production as soon as possible. This would enter service as "Tank, Infantry, Mark IV" later named Churchill. The first pilot Churchill was finished by November 1940.

The decision to cancel the order for 100 A20 was made in June 1940 and that the four pilot models - constructed of mild steel - would be used for component testing.