The General Grant Tank on display at Army Museum of SA, is almost certainly one of 1900 transferred to the Australian Army from the USA during WWII.
It was transferred to Woomera in the early 1950s and probably was used during the firing trials of Project E3, a wire guided anti tank rocket later designated Malkara. It streamed a wire behind it as it flew with an operator controlling the rocket by sending signals down the wire to the rocket. Malkara was tested in Woomera during December 1954.
The Department of Defence Publication “Fire Across the Desert” details the use of the General Grant Tank as a safe haven for the pilots of the Malkara Rocket Firing Trials to protect them from mishap.
Trials on 6 December 1954 prepared to fire 6 rockets at a target some 2km away. The first round went high over the top of the 5m high target. The wind dropped and the second round streaked towards the target, rising above the target, but the pilot quickly brought it back on course and it hit barely 1m from the centre of the target, leaving the control wire trailing through a ragged hole.
The pilot, Reyn Keats, formerly a bank clerk and later a Professor of Applied Mathematics, became the first person at Woomera to fire and guide a missile to its target. Keats and his reserve pilot, Ted Hayman, were protected by the old General Grant tank.