The Naiade was a French Simonot type Sirene Class submarine of 548 tons displacement surfaced launched in 1925. The Naiade was powered by two sets of 2-cycle Sulzer diesel engines providing a top speed of 14 knots surfaced and 7.5 knots submerged and a range of 3200 km at 10 knots on the surface, and carried a complement of 40. She could dive to a depth of 45 fathoms. Armaments consisted of one 3-inch anti-aircraft gun; two machine-guns and seven 21.7 inch torpedo tubes. Research Naiade