Gerald Bertram Crothers Sumner lived in Woking, Surrey. A member of the Oxford Univercity Car Club he raced at Brooklands in 1933 in the Oxford and Cambridge Univercity Handicap. Cambridge won 22 points to 3.
He was one of the leading lights in the Junior Car Club movement at Brooklands pre-war and raced many different vehicles from a tiny GN to the big V12 Delage LSR car.
In 1939 he raced a Jackson tuned 1087cc MG, winning a three lap race on the outer circuit at an average speed of 111.85 mph. That year he was elected as a member of the BRDC.
After the war he raced his MG finishing 4th in the Gransden Lodge Trophy in 1946. He quit racing and moved to Majorca where he ended his days.
His brother Bobby also raced GNs.