Steve Sullivan worked in the Development Division of Frankenstein and Sons Ltd, a waterproof clothing manufacturing company based in Manchester. Along with his colleague Ian B Wright, Sullivan was involved in the designing and testing of a full pressure suit in collaboration with A V Roe & Co Ltd and the Aeroplane and Armament Experimental Establishment at Boscombe Down. The suit was intended for use by pilots of the Royal Air Force Bomber Command flying V Bombers at very high altitudes. The development of ultra high altitude protective clothing came to an end in Britain when the V-Bomber force operations changed to relatively low altitude interdiction.