18 April 1938. 10:00hrs. Farnborough, England.
Vulcan Foundry, despite all the delays due to shortage of components and armour plate, and especially the Wilson epicyclic gearbox, had finally delivered the A12E1 to the MEE for testing. When the mock-up had been looked at the previous year some changes had been suggested, and these were incorporated into the prototype, including the provision of a Close Support howitzer in place of the 2-pdr in some of the tanks.
The twin AEC diesel engines behaved beautifully during testing, though there were cooling problems that would need to be resolved before the production model could be produced. The six-speed Wilson pre-selector gearbox and Rackham clutches also performed fairly well in conjunction with the Vickers’ designed bell-crank ‘Japanese’ type commercial suspension just some minor modifications would need to be made for it to work a bit better. The trial team also recommended the provision of air cleaners if the tank was to be used in ‘colonial’ settings.
The thickness of the armour on the A12E1 made a sub-frame unnecessary, so the plates and castings were bolted together resulting a very smooth finish. It was noted that this form of construction needed accurate castings and many skilled-man hours to complete it. The question was asked therefore about when the production types would actually be delivered for use. The initial order for 65 ‘off the drawing board’ would likely be increased by at least 100 more, so Fowlers of Leeds, Ruston Hornsby and the LMS were all approached to take part, under the parentage of Vulcan Foundry, to contribute to production.