Donald Macintyre joined the Royal Navy in the twenties, and, having qualified as a pilot n the Fleet Air Arm, flew fighter aircraft from the carriers H.M.S. "Hermes" on the China station and H.M.S. "Courageous" in Home waters. After a serious illness he was passed fully fit for sea service again, and obtained command of H.M.S. Kingfisher, a new type of anti-submarine ship where he first acquired his overriding interest in sub-marine hunting. Between 1940 and 1944 (when he was transferred to a shore posting) he was among the most successful submarine hunters in any Allied navy, transforming the Battle of the Atlantic by his successes against the U-boat menace. After the war ended he wrote numerous books, among them U-Boat Killer, The Battle of the Atlantic and The Naval War Against Hitler.