The Light Tank Mark I of 1930 was the first light tank to be ordered into production for the British Army, although only a very small number were produced, and the type was used for experiments and trials.
During the 1920s Sir John Carden had developed a series of light tanks, all descended from the original Carden Loyd Tankette. At first these were developed privately, but eventually the War Office became involved, and the Carden Loyd Mk VII was given an official designation, becoming the A4E1. By this time the Carden Loyd company had been taken over by Vickers. The Carden Loyd Mk VII was a two-man tank with a low bevel-sided turret and an external girder which connected the four road wheels.
The Mk VII was followed by the Carden Loyd Mk VIII, which became the Army's Light Tank Mark I, while retaining the A4 designation. The Light Tank Mark I was a two man tank armed with a single .303in Vickers Machine Gun. The tank was built around a chassis framework, with the armour and major automotive components attached the framework. Power was provided by a 59hp Meadows engine. The external girder was removed, and the four road wheels were carried on two pairs of two-wheel leaf-sprung bogies with three return rollers mounted on the hull and a rear idler wheel that was used to control track tension. The machine gun was carried in a flat sided cylindrical turret, and was protected by an armoured jacket that caused problems with over-heating in the Mark I. Steering was accomplished by removing power from one track or the other, with brakes to allow for tighter turns.
In 1930 the Royal Tank Corps didn't believe that tank-vs-tank combat would be very common, instead believing that the main threat to each sides tanks would come from the others un-armoured anti-tank guns. At most the light tanks would clash with other similar light tanks. As a result the entire family of tanks based on the Light Tank Mark I, which ended with the three-man Mark VI, were under-gunned and under-armoured, and suffered heavy losses during the short campaign in France in 1940.
The Light Tank Mark I was produced in very small numbers, with four or five vehicles produced (sources differ). Four were given Experimental Numbers, from A4E2 to A4E5, but it isn't clear if the Carden Loyd Mk VIII was a fifth vehicle, or an earlier designation for the A4E2. The Mark I was followed by five examples of the Light Tank Mark IA, with experimental numbers A4E6 to A4E10.
Most of the Marks Is were used for running trails or for other experiments, most notably the A4E2 which was later turned into an experimnental mount for two .5in anti-aircraft machine guns in an open circular mount and the A4E4 which was given Horstmann suspension.
Light Tank Mark I, A4E2 to A4E5
Hull Length: 13ft 2in
Hull Width: 6ft 1in
Height: 5ft 7in
Weight: 4.8 tons
Engine: 58hp Meadows EPT 6-cylinder
Max Speed: 32mph
Max Range: 160 miles operational radius
Armament: One .303in Vickers machine gun
Armour: 14in max, 4in min