He was the captain of the aircraft carrier Ark Royal when she was sunk in November 1941, but went on to serve in Combined Operations, playing an important role in the development of landing craft.

[1] Promoted to commander on 31 December 1927, Maund served as Naval Assistant Secretary to the Committee of Imperial Defence until October 1930, when he was appointed Executive Officer of the aircraft carrier Furious in September 1931.

From April to June 1940 he served as Naval Chief of Staff to the Flag Officer, Narvik, during the Norwegian campaign, receiving a Mention in Despatches on 26 September 1940.

Maund was officially placed on the Retired List on 8 July 1943; but on 25 August 1943, he was appointed Director of Combined Operations, India, based in Bombay:[1] he arrived there on 16 October.

[1] Maund became a director of the scientific instrument makers A. Kershaw & Sons, Ltd. of Leeds, and wrote a book Assault from the Sea, published in 1949 by Methuen & Co., London, which was his account of the development of the Royal Navy's landing craft and their use operationally between 1939 and 1945.