OVERVIEW:The Oyashio class is a series of Japanese diesel-electric attack submarines operated by the JMSDF. 

DETAILS:The submarines are larger than the earlier Harushio class, to provide space for a flank sonar array.

SOURCES: Saunders, Stephen (2004). Jane's Fighting Ships 2004-2005. Jane's Information Group. p. 384. ISBN 0-7106-2623-1.