HMS Sealion
Straits of Otranto
April 5th 1939
Even through the British had been the nation during the interwar period who had pushed the hardest for restrictions on submarines didn’t keep them from building them. Then again, the Royal Navy had to find ways to be able to defend a number of oceans and seas from the Americans, Germans, the French, and Italians. Not an easy task even more so since they have to follow international treaties on capital ship tonnage. Even more so that some boats would work well in some areas and not others. The Mediterranean Sea was a critical life line in the British system and the massive Y Class Submarines[1] didn’t cut the mustard in the Mediterranean. It was where the S Class submarines came in.
The S Class was one of the smaller submarine classes currently in service with the Royal Navy. They had been designed from the word go with the idea they would primary be operating in either the Mediterranean or the North Sea. They handle fairly good in those restricted waters, but the problem was there wasn’t enough of them. HM Treasury had told the Royal Navy it couldn’t had everything it wanted. What happened was the Admiralty had decided to reduce submarine programs to allow for increase battleship production. Well that had been prior to the start of the war. With a war on the Exchequer was writing blank checks now, but it would take time to get the newly approve units into the fleet leaving only 18 S Class boats for action between the North Sea and Mediterranean.
HMS Sealion was one of one four S Class boats assigned to the Mediterranean. The rest were currently assigned to operations in the North Sea. They working with either relics from the Great War or boats designed to operate either in the Atlantic or Indian Oceans. But then again the Royal Navy was overstretched already as one of the keys they had been counted on had broken ties with the Empire. However, once they win this war there were plans do deal with the treason of the Imperial Federation. At the moment, they had to focus on knocking Germany and her allies out of the war. It was why she had been assigned to operate in the Adriatic.
It was hoped that the Italians would be less guarded in the Adriatic since the collapse of the Austro Hungarian Empire. They had to hurt the small Italian merchant fleet and attacking their convoys from Italian Libya to Europe was a challenge. So it was hoping the Adriatic would be a better hunting ground. However, what the Sealion and her crew found as they were crossing the Straits of Otranto was something very different. Unknown to them they had ran across the rear part of the Italian fleet that was being used to support the invasion of Corfu.
The Italians had two forces for the invasion of Corfu. The first was being led by the Roma Class Battleships which were the best battleships the Italians had. Then they had the older Andrea Doria Class and other older ships covering the rear part of the fleet. This was to keep the units under the protection of the Roma Class safe if the British or Greeks found the rear of the fleet. The Andrea Doria class had been slated to be modernized come 1941 or 42 once the Ammiraglio di Saint Class was ready to be commissioned. However the war ended that idea. So they were covering the tail end of this fleet.
After putting their boat into position the Sealion launched a full spread of torpedoes Caio Duilio. With the S Class having six tubes forward meant a full spread that major power behind it. True it wasn’t the power of the Y Class, but six torpedoes wasn’t nothing to laugh at either. Of the six torpedoes, three of them found their mark of the Caio Duilio. The Sealion would come away with only light shock damage after four hours of depth charging by Italian destroyers. The Caio Duilio through wasn’t as lucky as she took major damage from all three torpedo hits. It was only due to a super human effort by her crew that she made it back to port. This was largely thanks to the interwar years training of damage control and putting time into making the Italian Fleet a fleet that could change the British for control of the Med in wartime instead of banking on the idea of being a fleet in being.
[1] The Y Class is a truly massive bastard of a submarine. 12 tubes forward (8 are reloadable, 4 are external), 4 tubes aft, 4 inch deck gun. Basically the British Fleet Submarine