St Nazaire Raid - Composition of The Raiding Force

Composition of The Raiding Force

The revised Combined Operations plan required one destroyer to ram the dock gates and a number of smaller craft to transport the Commandos. The Royal Navy would therefore provide the largest contingent for the raid, under the overall command of the senior naval officer, Commander Robert Ryder. The ship selected to ram into the dock gates was HMS Campbeltown, commanded by Lieutenant Commander Stephen Halden Beattie. The Campbeltown was a First World War destroyer and had previously been the USS Buchanan in the United States Navy. She had come into RN service in 1940 as one of 50 destroyers transferred to the United Kingdom under the Destroyers for Bases Agreement.

Converting Campbeltown for the raid took ten days. She had to be lightened to raise her draught to get over the sand banks in the estuary. This was achieved by completely stripping all her internal compartments. The dockyard removed her three 4 inch (100 mm) guns, torpedoes and depth charges from the deck and replaced the forward gun with a light quick–firing 12 pounder (3"). Eight 20 mm Oerlikons were installed on mountings raised above deck level. The bridge and wheelhouse were given extra armour-plate protection, and two rows of armour were fixed along the sides of the ship to protect the Commandos on the open deck. Two of her four funnels were removed, and the forward two were cut at an angle to resemble those of a German destroyer. The bow was packed with 4.5 tons of high explosives, which were set in concrete. It was decided that the explosive charge would be timed to detonate after the raiders had left the harbour. To prevent the Germans towing her away, the crew would open the ship's seacocks before abandoning the ship. Should she become disabled or sunk before getting to the dock, four motor launches had been detailed to take off the crew and put the commandos ashore. The charge would be reset to explode after the last boat had left.

Other naval units involved were two Hunt class destroyers, HMS Tynedale and Atherstone, which would accompany the force to and from the French coast and remain out at sea during the raid. A Motor Gun Boat (MGB 314) was the headquarters ship for the raid, with Commander Ryder and the commanding officer of the Commandos on board. A Motor Torpedo Boat (MTB 74), commanded by Sub-Lieutenant Michael Wynn, had two objectives: If the outer Normandie dock gates were open, she had to torpedo the inner dock gates. If the gates were closed she would instead torpedo the gates at the old entrance into the St Nazaire basin. To assist in transporting the Commandos, 12 motor launches (ML) were assigned from the 20th and 28th Motor Launch flotillas. These boats were re-armed with two Oerlikon 20 mm guns mounted forward and aft to complement their twin Lewis guns. At the last minute another four MLs were assigned from the 7th Motor Launch flotilla (see Footnotes for flotilla details). These four boats were also armed with two torpedoes each. Instead of transporting the Commandos, these boats were to engage any German shipping found in the estuary. All the MLs had a 500 gallon auxiliary fuel tank fixed to the upper deck to increase their range. The S class submarine HMS Sturgeon would leave before the rest of the convoy and be in position to act as a navigational beacon to guide the convoy into the Loire estuary.

The man selected to lead the Commando force was Lieutenant Colonel Charles Newman; his own No. 2 Commando would provide the largest Commandos contingent, 173 men, for the raid. The Special Service Brigade headquarters used the raid to provide experience for their other units and 92 men were drawn from Nos 1, 3, 4, 5, 9, and 12 Commandos. The Commandos were divided into three groups; One and Two would travel in the MLs, three would be in the Campbeltown. Under the command of Captain Hodgeson, Group One had the objectives of securing the Old Mole and eliminating the anti-aircraft gun positions around the southern quays. They were then to move into the old town and blow up the power station, bridges and locks for the new entrance into the basin from the Avant port. The capture of the mole was a major objective, as it was to be the embarkation point for the evacuation after the mission. Group Two, under the command of Captain Burn, would land at the old entrance to the St Nazaire basin. Their objectives were to take out the anti-aircraft positions in the area and the German headquarters, to blow up the locks and bridges at the old entrance into the basin and then to guard against a counter-attack from the submarine base. Group Three was under the command of Major William 'Bill' Copland, who was also the Commandos' second in command. They were to secure the immediate area around the Campbeltown, destroy the dock's water-pumping and gate-opening machinery and the nearby underground fuel tanks. All three groups were subdivided into assault, demolition and protection teams. The assault teams would clear the way for the other two. The demolition teams carrying the explosive charges only had sidearms for self-defence; the protection teams, armed with Thompson submachine guns, were to defend them while they completed their tasks. The Commandos were aided in their planning for the operation by Captain Bill Pritchard of the Royal Engineers, who had pre-war experience as an apprentice in the Great Western Railway dockyards and whose father was the dock master of Cardiff Docks. In 1940, while part of the British Expeditionary Force in France, his duties had included examining how to disable the French dockyards if they were captured. One of the dockyards he had studied was St Nazaire, and he had submitted a report detailing how to put the dock out of action.