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Grey Havoc

The path not taken.
Senior Member
Oct 9, 2009
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An interesting midget submarine that became a vital part of an even more interesting operation of the Decima Flottiglia MAS that came close to fruition in 1943 (it was ultimately scheduled for December of that year, but events intervened).

Development of the CA-class had begun pre-war, in 1938, undertaken by a division of Caproni on behalf of the Regia Marina (the project was initially known as Project 'G' [note that some sources state the overall project began in 1937]). The design, along with that of the coastal defence CB-class, could trace their linage back to the Italian A- and B-class submarines of WWI. The two CA prototypes had been placed in storage in 1940 after successful testing, where they were discovered by the 10th Assault Vehicle Flotilla in 1942. (In their initial incarnations, the two CAs had apparently been relatively mechanically fragile and had some manoeuvring problems, leading to efforts being concentrated on the CB class. The MAS ultimately fixed those problems after reactivation, though not before the CA-1 had been lost during training. While CA-1 was apparently salvageable, it is unclear if it was raised before the Armistice of Cassibile. Two more CA-class submarines had been ordered for the MAS in the meantime.)

With regards as to the mothership: Italian submarine Leonardo da Vinci (1939)
Note that the name should actually be R.Smg. Leonardo da Vinci, R.Smg. standing for Regio Sommergibile, or Royal Submersible.
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ACCESS: Confidential
Apr 13, 2006
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I have read a lot of material on Italian midget submarines, both from World War One and the CA and CB class midgets. I would like to find out if there were other Italian midget submarine designs from the 1920's-1940's that were never built. For example, Caproni designed the CA and CB-classes - did they design other midget submarine classes? Did other Italian companies that one would not think of for shipbuilding design submarines?