The Mocenigo was an Italian Marcello Class ocean-going submarine of 941 tons displacement launched in 1937. She was powered by two Fiat diesel engines providing a top speed of 17 knots surfaced and nine knots dived, could dive to a depth of 58 fathoms, and was armed with two 3.9 inch guns; two 13 mm anti-aircraft guns and eight 21-inch torpedo tube...