In 1941, the head of the United States Ordnance Department travelled to Britain to learn of their experience, ideas and requirements for the future.

Among the discussion was the possibility of designing a well-armed and armored combat vehicle, one that was stronger than the British Churchill infantry tank then in production.

Testing of the pilot model which was completed in 1944 showed the vehicle to be much too heavy for practical use.

By this time, the British Army was satisfied with the Churchill and its cruiser tank designs and further production of the T14 was halted.

[4] The British had developed the Heavy Assault Tank A33 "Excelsior" design to the same specification as the T14 but this did not go into service either.