Lionel McDonald was born in Winchester, Hampshire on 10 August 1890, the son of Richard Henry and Sophia Emma McDonald. He joined the Royal Navy as an Artificer Apprentice on 16 August 1906. By 8 August 1917 he was an Engine Room Artificer Third Class and promoted to Acting Mate (E). He was further promoted to Acting Engineer Lieutenant on 6 August 1919. He was appointed to the Submarine Flotilla Leader HMS ROYAL ARTHUR ‘for duty with Submarines‘ on 15 April 1920. On 2 September 1920 he was appointed to HMS K22 as the Engineer.

An appointment to the Submarine Depot Ship HMS LUCIA for duty with submarines followed on 30 January 1923. He is reported to have died of Carbon Monoxide poisoning on 6 November 1924. It is understood that he committed suicide whilst of unsound mind.  Lionel McDonald was the husband of Gladys Maud McDonald (née Yates) from whom he was separated.