Geoffrey Wellum was born in Walthamstow, and educated at Forest School, Snaresbrook. Aged seventeen, he joined the RAF on a short-service commission in August 1939 and served with 92 Squadron throughout the Battle of Britain. In March 1942 he went to 65 Squadron at Debden as a Flight Commander and from there to Malta later that year. He led a group of eight Spitfires off HMS Furious to Luqa during Operation Pedestal.

Returning to England, Wellum became a test pilot on Typhoons at Gloster Aircraft. He later became a gunnery instructor until the end of the war. He stayed in the RAF after 1945, serving in Germany as a staff officer, followed by a four-year tour of duty with 192 Squadron. Wellum left the RAF in 1961 to take up a position with a firm of commodity brokers in the City of London until his retirement to Cornwall. He died in July 2018, aged ninety-six.