Initial assignments In February 1939, prior to the outbreak of the Second World War, Mayne joined the 4th Battalion (
Extra Reserve) of the
Royal Ulster Rifles at Newtownards before receiving, the following month, a
commission in the
Royal Artillery and was posted to 5 Light Anti-Aircraft
Battery (5LAA), in 8 Anti-Aircraft Regiment, later
8 (Belfast) Heavy Anti-Aircraft Regiment. Following
Winston Churchill's call to form a "butcher and bolt" raiding force following the
Dunkirk evacuation, Mayne volunteered for the newly-formed
No. 11 (Scottish) Commando being seconded to the
Cameronians (Scottish Rifles). He first saw action in June 1941 as a
second lieutenant with 11 Commando during the
Syria–Lebanon campaign. Mayne successfully led a section of men during the
Battle of the Litani River in
Lebanon against
Vichy French Forces. The operation was commanded by Major Dick Pedder,
Highland Light Infantry, who was killed in action. Mayne played a distinguished part in the raid, being
mentioned in despatches.
Transfer to the SAS Mayne's friend Lieutenant
Eoin McGonigal recommended him to Captain
David Stirling McGonigal was a fellow
subaltern in No. 11 (Scottish) Commando, and an early volunteer for the
Special Air Service (SAS), then known simply as the "Parachute Unit". It is widely believed that Mayne was under arrest for hitting his commanding officer,
Lieutenant-Colonel Geoffrey Keyes when Stirling met him. According to Keyes' personal diary he was not at 11 Commando officers' mess at
Salamis on
Cyprus on the evening of 21 June 1941, the date on which Mayne was accused of beating up a fellow officer, Major Charles Napier. Keyes had stayed the night elsewhere, and arrived at Salamis the following day, 22 June 1941, when the trouble was already over. Keyes states in his diary that he conducted an investigation and found Mayne responsible. Keyes' diary makes it clear that Mayne was brought before Brigadier Reginald Rodwell, on 23 June, for assaulting Napier, the second-in-command of his battalion. Mayne had a grudge against Napier, who had not taken part in the Litani raid, and who, according to a serving member of 11 Commando, had shot Mayne's dog in his absence. Mayne was furious about this, having been attached to his loyal pet. Keyes' diary records that, on the evening of 21 June, after drinking heavily in the mess, Mayne waited by Napier's tent and assaulted him when he returned. Keyes also records in his diary that Mayne was dismissed from 11 Commando the following day, 23 June, but does not state that he was arrested.
SAS – 1941 and 1942 From November 1941 through to the end of 1942 during the
Western Desert Campaign, Mayne participated in numerous night raids deep behind enemy lines in the deserts of Egypt and
Libya, where the SAS wrought havoc by destroying many enemy aircraft on the ground. Mayne pioneered the use of
military jeeps to conduct surprise hit-and-run raids, particularly on
Axis airfields. The National Army Museum stated that Mayne had "a personal tally of more than 100 aircraft destroyed." The first successful raid at Wadi Tamet in Libya on 14 December 1941, where aircraft and petrol dumps were destroyed, helped keep the SAS in existence, following the failure of the previous initial raid behind enemy lines at Sirte. For his part in the Tamet raid Mayne was awarded the
Distinguished Service Order (DSO). Promoted to lieutenant after the second raid of Tamet on 27 December 1941, Mayne also received a mention in despatches on 24 February 1942. Mayne's official report on the Tamet raid notes: Mayne took part in the most successful SAS raid of the Desert War when, on the night of 26 July 1942, with eighteen armed jeeps, British and French commandos
raided the Sidi Haneish Airfield. Avoiding detection, they destroyed up to 40 German aircraft escaping with the loss of only three jeeps and two men killed in action.
Commanding officer Following Stirling's capture in January 1943, 1st SAS Regiment was reorganised into two separate parts, the
Special Raiding Squadron (SRS) and the
Special Boat Section (the forerunner of the
Special Boat Service). As a
major, Mayne was appointed to command the Special Raiding Squadron and led the unit in
Sicily and Italy until the end of 1943. In
Sicily, Mayne was awarded a
bar to his DSO. The official citation reads as follows: In January 1944 Mayne was promoted to lieutenant-colonel and appointed
commanding officer of the re-formed 1st SAS Regiment. He subsequently led the SAS with great distinction and valour through the final campaigns of the war in France, the Netherlands, Belgium, Germany and Norway, often campaigning alongside local resistance fighters including the
French Maquis. In recognition of his leadership and personal disregard for danger while in France, where he trained and worked closely with the
French Resistance, Mayne received a second bar to his DSO. The official citation stated: During the course of the War, Mayne became one of the
British Army's most highly decorated soldiers receiving the DSO with three bars. == Recommendation for the Victoria Cross ==