Vian, Sherbrooke, and command of HMS Cossack

Philip Vian was still a captain when he commanded Cossack, and the Tribal-class destroyer was not his first command. He took over during the Altmark incident because Robert Sherbrooke had exhausted himself running the ship. The handover was an immediate response to the strain of command, rather than the beginning of Vian's command career. Sherbrooke later won the Victoria Cross while leading O-class destroyers against German heavy cruisers.