Good afternoon, guys!
As the anti-republican coup d´etat was a failure, the two parts found themself badly prepared for a war, specially a long one. The SCW is a conflict very studied, and important conclusions (fair and wrong) were obtained from it. But mainly about land and air warfare, but in my point of view, very little was wrote about the maritime part of it, which was a critical point, because, as any long war, SCW was a war of supplies, so it was critical keeping open the sea lanes for your own shipping and denying them to your enemies.
As I previously said, the most critical factor of the war was the only professional corps of the Spanish Army, the Army of Africa, which was garrisoned in Northen Morocco.
But as most of the spanish fleet remained loyal to the republican leftist goverment, crossing the straits was very difficult, and only done in few times, and the air bridge was clearly insufficient for crossing the 30,000 men needed in the peninsula. In addition, the main southern rebel harbour, Cadiz, was disconected from the rest of the rebel forces, and the good harbours in Galicia (northwestern corner of Spain) were badly communicated (only one railroad and one road) with the Castillian Plateau. So, it was of paramount importance an offensive of the Army of Africa from their beach heads at Cadiz, Algeciras and Seville, first to secure Andalusia, then to connect with the rest of the rebel forces securing a friendly border (Portugal) in their backs.
As the flag officers were in the rebel side, they understood clearly the need of an aggressive submarine campaign (the 12 submarines of the Spanish Navy were with the republicans), so as early as September 1936 an agreement with the friendly fascist Italy and nazi Germany was attained: 2 German submarines and 6 Italian boats patrolled the western Mediterranean Sea and the Spanish coast. In the next months, the Germans torpedoed and sunk a republican submarine, and the Italians torpedoed and damaged a 6 inch armed cruiser. But this caused alarm to the British Admiralty, which menaced to sunk any foreign or suspicious submarine. Trying to avoid any clash with the powerful RN, Germany retired their two boats, and Italy sold a pair of Archimede class submarines to the Spanish Nationalist Navy (and putting other 4 under mixed spanish-italian command).
The lead of the class, Archimede was renamed C-3, and Torricelli C-5 (trying to confuse the republican intelligence: 2 boats of the Spanish C class were lost the previous months); later both were renamed as General Mola and General Sanjurjo respectively. General Mola was the most successful submarine of the SCW and of the Spanish Navy, with 4 vessels sunk, one of them, Cabo Palos loaded with soviet armament, and 1 damaged.
Cabo Palos, when built was the biggest and most modern vessel of the Spanish merchant fleet, one of a class of two built for Ybarra and among the first spanish built ships with diesel engine. At the beginning of the SCW it was requisitioned and used as a transport between the Spanish Mediterranean harbours and the soviet Black Sea ones. When sunk, Cabo Palos was coming from Odessa with a load including 30 Polikarpov monoplane fighters, more than a hundred M-1937 45 mm/46 cal. anti-tank guns with 300,000 rounds for them, 15,000 Mosin Nagant rifles, spares for tanks, cannons and machine guns, and nearly 60 million of 7.62x54R rounds.
General Sanjurjo was involved in the sinking of the motor vessel Ciudad de Barcelona with a heavy toll of lives, which was travelling from Marseille to Barcerlona with more than 500 volunteers for the International Brigades.
Both boats survived the war and until the arrival of a Type VII German submarine, were the best boats of the Spanish Silent Service, and were based at Cartagena. Soon after the war, the stern 100 mm guns were landed. In 1943 while rescuing German sailors from a sunk U-Boat, General Sanjurjo was involved in an incident with a British T class submarine. Subsequently, both Spanish ex-Italian submarines were painted white for avoiding further confusion.
Both boats were paid off in 1958, after the arrival of American aid.
Credits: Thanks a lot to Colombamike, for the blueprints, the comments, the stabilization keels and the canvas detail
. And also thanks to Ian, as I previous said him: "plagiarism is the most sincere form of praise" (the shading of the saddle tanks was made trying to mimic the shading of Ian`s nice series of american submarines
). Cheers.