
Born January 28, 1909 in Streatham, London.
Crabb and his mother Beatrice and father Hugh lived in poverty. Nicknamed "Buster," Crabb served as a merchant seaman as World War II began and was commissioned into the Royal Nay Patrol service in 1941 after first serving as an army gunner. Because of an eye injury he was unable to travel to sea and volunteered for the dangerous task of mine and bomb disposal. He was assigned to Gibraltar in 1942 and aided other Navy divers in protecting British ships against Italian saboteurs. Italian frogmen ambitiously sought to install limpet mines to the hulls of British ships.
Initially Crabb was assigned to disarm bomb removed from ships, but he eventually asked to be trained as a diver. He was a quickly learner and received numerous commendations, including a George Medal. He was eventually promoted to the rank of Lieutenant Commander. Became the Principal Diving Officer for Northern Italy in 1943. A few years later he was stationed to Palestine and in 1948 he left the Royal Navy.
For a few years Crabb were in the private sector working for the Atomic Weapons Research Establishment at Aldermaston. He also worked with searching through sunken Spanish galleons.
In 1952 Crabb returned to active duty and was assigned to frogman duties in various ports. He searched and investigated sunken Royal Navy submarines. Married Margaret Player and continued on as a frogman, and in 1955 worked with another frogman, Sydney Knowles, investigated the hull of a Soviet ship, the Sverdlov.