David Howroyd joined the Sterling Group of Companies after completing his tool-making apprenticeship with the Plessey Company in 1944. He was ‘called up’ for National Service with the post-war RAF between 1946 and 1948, where his skills were especially sought due to the release of thousands of skilled RAF veterans into post-war industry. He returned to the Sterling Engineering Company in late 1948. After 1972 he became General Manager, and subsequently the Works Director of Sterling Armament Co Ltd.