ST. NAZAIRE: The Germans needed dry-dock facilities on the Atlantic coast before the [Tirpitz] could be deployed effectively against allied convoys. The only port capable of handling it was St. Nazaire on the French coast. There were others… but none of operational value…. From within the Planning Division in the Admiralty the idea emerged to destroy the dock gate at St Nazaire…. Denying the Germans use of the dry-dock would effectively neutralize the threat the Tirpitz posed… but how?…
The outline plan was simple. The selected vessel, packed with high explosives in the bow, with troops and crew in protected areas, would ram the outer dock gate at speed and stick there. They would disembark and take cover behind a nearby air-raid shelter. The ship would then blow up destroying the gate. An MTB would then pass through and fire specially designed torpedoes at the inner gate which would collapse under pressure when the tide went out damaging the submarines berthed in their protected pens. The troops and crew would then destroy as many dockyard targets and withdraw in fast motor launches….
The planners themselves had doubts about the withdrawal phase….
The raid was to be led by HMS Campbeltown, an American lend-lease destroyer (USS Buchanan). It was especially refitted for the task. Her interior was stripped, the bridge armour-plated, and additional protection provided…. The accompanying motor launches (MLs) were to carry 150 Commandos… the ML fleet was firstly increased to ten and then to 14….
The fleet sailed from Falmouth at 3 pm on the 26th of March with MGB 314 at the head and two escort destroyers flanking the MLs and HMS Campbeltown….
Each boat flew the German flag to confuse the enemy and delay identification…. The Campbeltown crept through at 5 knots, touching bottom twice…. The German flags were replaced with the White Ensign when the fleet was still two miles from its target. The Germans opened fire during the final 15 minutes of the run in during which half the men aboard the MLs were either killed or wounded….
At 0134 hours Campbeltown was successfully driven at speed into the dock gates just 4 minutes behind schedule and was relieved of most of her crew by MGB 314 while MTB 74 deployed her delayed action torpedoes in the foundations of the old entrance dock gate.
Captain Ryder, CO of the Naval forces, went ashore and satisfied himself that Campbeltown was both scuttled and embedded in the loch gate. At 0230 hours Ryder decided to withdraw. By this time more than half of his craft had been destroyed and the remainder were riddled….
The delayed action fuses detonated the high explosives in the Campbeltown's hold at noon on the 28th. Forty German officers were aboard at the time and 400 other ranks were nearby on the quay. All were killed in the blast. The dock gates were destroyed and were not repaired until after the war. On the evening of the 29th the delayed torpedoes were activated causing further damage and German casualties. Regrettably many needless French casualties were caused by jittery German soldiers who believed that the raiders were still in their midst.
Of the 241 Commandos who took part 59 were posted as killed or missing and 109 captured. 85 Royal Navy personnel were killed or missing and a further 20+ captured. Many others were wounded. 5 other ranks returned to England via Spain…