Bombs, guns and depth charges were all used against her, but unlike her five sisters, who were captured, bombed and scuttled, the Free French Navy’s Rubis carried out mission after mission throughout the Second World War, from the Battle of Norway to the eve of D-Day. Today the wreck of the Rubis lies silent and deep, the only survivor of an entire class of submarines destroyed in the Second World War.
Full military honours
The French submarine Rubis was designed in 1925 and launched in 1931 before being commissioned in 1932. Built in the Toulon yards in the South of France, the Rubis was the fourth of a series of six submarines. The class prototype, the Saphir, was built in 1930, followed by Turquoise, Nautilus, Rubis, Diamant and in 1937 Perle.
Initially all six submarines were stationed at Toulon, but in 1936 the Rubis was despatched to Cherbourg so that its crew could train in laying mines in the depths of the Atlantic Ocean.
Early in 1939 the Rubis was sent back to the Mediterranean and stationed at the port of Bizerte in Tunisia, which was then a French colony. Later, the vessel was attached to the 9th Submarine Fleet based at Dundee in Scotland. Under the command of Captain Georges Cabanier, the Rubis received her first orders from the French Admiralty early in 1940. They concerned an Allied operation with the aim of protecting the Finnish coastline in the event of an attack by the Russians. On 9 April the German Wehrmacht invaded Denmark and Norway unexpectedly, and the Allies immediately began operations to mine the Norwegian waters to try to block the transport of steel and other metals indispensable to the German war effort. All available submarines were used in this operation.
On 3 May the Rubis and other vessels mined the entrance to the Egersund Fjord on the Norwegian coast. After two further missions in the same waters the French Admiralty recalled all its vessels involved in the mine-laying operations. Only the Rubis remained to complete one last mission – the mining of the Trondheim Fjord, in which a significant part of the German North Sea Fleet was anchored. Following the signing of the armistice between France and Germany on 22 June, and between France and Italy on the 24th of the same month, the vessel was sequestered by the British. While she maintained the same crew and captain she continued to fight on behalf of the French Resistance under the British flag.
Records show that in the course of 28 missions the submarine laid 683 mines, which caused the sinking of 15 tenders, seven patrol boats and a 4,360-tonne freighter, as well as seriously damaging a submarine.
At the end of the war the Rubis returned in triumph to Toulon, where her crew members were decorated with the highest French and British honours. Following a complete refit the submarine continued to be used by the French Navy for some years as a training vessel.
In 1950 she was transformed into a floating school for cadet submariners, and was later used as a target in sonar exercises. At the end of her long and glorious career the Rubis was spared the indignity of being broken up.
The Rubis was scuttled on the 31 January 1956 off Cap Camarat, between Cavalaire and St Tropez, thus preserving a page in the turbulent history of the 20th century. The wreck has proved to be of particular interest; so much so that over the years it has attracted countless divers.
The Rubis class of submarine was designed so that it could lay mines in enemy territory without having to surface and also launch torpedoes. All the 32 mines carried by the submarine were housed outside the principal pressurised compartment but within the hydrodynamic hull.
Each of eight wells on either side of the boat contained two mines, one on top of the other. Having reached a designated target zone, the submarine released the mines via a compressed air system. It was necessary to rapidly counter the loss of the weight of the mine in order to avoid surfacing suddenly in enemy territory. Older submarines released their mines through a hatch – with the new externally located system there was less risk of unwanted surfacing.
The mines were manufactured by Sauter & Harley and contained 220kg of explosive. As soon as they were positioned, these instruments of destruction automatically rose to the surface and were firmly anchored by a chain. The submarine’s four-stroke, six-cylinder engines were produced by Vickers-Armstrong and boasted power outputs of 650hp. The vessel used two Schneider electric motors when submerged, which gave it a maximum speed of eight knots. The Rubis could dive to a depth of 50m and operate at a periscope depth of 15m. Two Schweizer Oerlicher cannons were installed on the submarine’s deck and she was also armed with five torpedoes that could be launched from the stern.
The Rubis now sits upright on a sandy sea bed at a depth of 40m, almost as if it had been deliberately positioned. In spite of the considerable depth, when the water is clear the wreck can almost be seen from the surface. The wreck’s historical past has given the Rubis a halo of mystery and divers are immediately struck by a sense of awe.
The vessel’s position accentuates this impression – the submarine is lying on its keel, as if ready to launch an attack on an unseen enemy. There really is a sense that at any moment the Rubis’s electric motors might start up and it could cruise off into the distance. The wreck is 66m long, so it is possible to explore both sides in a single dive. It is not advisable to enter the submarine through the narrow hatch, firstly because 15-litre tanks or twin tanks are too bulky, and secondly because visibility is virtually zero due to heavy sediment.
It is important to remember when planning your dive that at certain times there are strong currents around Cap Camarat.
The submarine is still in good condition, even though many components such as the conning tower, the gun platform and the covers over the bays housing the mines have corroded. The plates of the Rubis are not as heavily covered with vegetation as those on the wreck of the Togo, which is located nearby.
Sea fans and sponges can be found on the flanks of the submarine, while torpedo tubes and cracks and niches house enormous conger eels, moray eels and scorpionfish. However, while the marine life on the Rubis is undoubtedly spectacular, it is the conning tower, mine housings, elevator and cable cutter on the bow that are likely to really capture divers’ imaginations. Look closely at the wreck, with all its wonderful examples of early 20th-century engineering, and perhaps, for a fleeting moment, you’ll be able to picture the vessel in its prime, heading off on another glorious mission.