 A variant of the 300 was the Argus 350, which allowed external access to its core to allow direct memory access.This improved performance of input/output, avoiding having to move data via code running on the processor.The 350 was used in various military simulators, including the Royal Navy for frigate, submarine and helicopter based anti-submarine training, and the Royal Air Force for a Bloodhound Mk.II simulator and the Vickers VC10 flight simulator built at Redifon and delivered to RAF Brize Norton in 1967.