- Wright, Ken
- WWII operations
- RAN Ships
- None noted.
- December 2010 edition of the Naval Historical Review (all rights reserved)
The WW II battleships of Hitler’s Kriegsmarine prowled the convoy routes of the North Atlantic, pushed beyond the Equator, challenged the enemy in the arctic blizzards of the Barents Sea and fought amongst the freezing ice flows of the Denmark Strait. They sank the British battle cruiser, HMS Hood and the aircraft carrier HMS Glorious. They destroyed an impressive number of merchant ships and humbled Britain’s naval pride by breaking through the Dover Straits in broad daylight against all odds. The British Prime Minister Winston Churchill considered them to be a greater threat to the Empire’s seaborne trade than the U‑Boats. The mere mention of the Deutschland (Lutzow), Admiral Scheer, Graf Spee, Gneisenau, Scharnhorst, Bismarck, Prinz Eugen, Hipper and Tirpitz around the hallowed halls of the British Admiralty were enough to give anyone there the nervous twitches.
Apart from any tactical victories, the value of the German battleships in tying up substantial numbers of aircraft, ships and manpower was a measure of the importance the British government placed on these ships. One example was the 52,600 ton Tirpitz, the largest battle ship in the Western Hemisphere when she was completed in 1939. From late January 1942, a large part of the British Home Fleet had to be allocated at all times to stop her breaking out into the Atlantic from the Norwegian harbour at Trondheim and raiding the convoys to Russia and other allied shipping lanes. The valuable resources that were used to keep the Tirpitz bottled up were at the expense of other areas of operations and so battleships in the Far East were lost, freighters in the Atlantic were sunk and Arctic convoys to Russia were decimated or delayed through the lack of protection from additional forces. So great was the fear of this mighty ship, she could never be left alone.
The British navy was to be denied the honour and pride of inflicting a naval defeat on this enemy of the empire. That honour went to their interservice rival the Royal Air Force who, on 12 November 1944, carried out an attack on the Tirpitz using six ton Tallboy bombs, mortally wounding the mighty ship. She capsized in a Norwegian fjord near the town of Tromsö taking approximately 700 crew to an icy grave. Until then, it had seemed frustratingly impossible to send her to the bottom of the ocean. Torpedoes, bombs, depth charges, submarines, mines, midget submarines, frogmen and aircraft from six aircraft carriers all failed.
If the Tirpitz was ever let loose in the sea lanes and was actually damaged enough to require repairs, there was only one port in occupied Europe capable of handling such a large ship, and that was St. Nazaire on the French Atlantic coast.
The Forme Ecluse Louis Joubert dry dock was, at the time, the biggest in the world, specially built to accommodate the giant French trans-Atlantic passenger liner Normandie, and capable of handling up to 80,000 tons. Also within the port were nine massive bomb-proof U-Boat pens built by Organisation Todt that were home to the 6th and 7th U-Boat Flotillas, with five more pens to be constructed. To thwart the possible use of the dry dock by the Tirpitz, or any other battleship for that matter, a plan was devised to destroy the massive lock gates (caissons) which stood between the dock and river Loire.
Destroy the lock gates
The idea was to use an old ship, packed with a demolition charge consisting of twenty-four Mark VII depth charges weighing a total of four and a quarter tons, encased in steel and set in concrete in the bow; sail from England to France undetected, sail six miles up the River Loire past batteries of guns and searchlights, ram the caisson and with a time fuse, explode the demolition charge destroying the lock gates. The attack was to be carried out while the Germans were otherwise distracted by a large bombing raid on St. Nazaire. In addition, a party of commandos would land and destroy machinery connected to the operation of the dry dock and any other useful targets of opportunity in the port.
As the German defences at St. Nazaire were considered the second toughest in Western France, surprise was the essential key element needed for any hope of success. Planning was completed in seven weeks and the operation was scheduled to be carried out in the early morning of 28 March because of tidal movements and the spring high tides. Demolition training took place at Burntisland, and rehearsals at Rosyth on the Firth of Forth, both in Scotland.