Silent Hunter, February 29, 1996.
Silent Hunter 2, November 5, 2001.
Silent Hunter 3, March 15, 2005.
Silent Hunter 4, March 20, 2007.
Silent Hunter 5, March 2, 2010.
Above you can see specific Silent Hunter series release history with actual dates, below is the broad generic yearly history of sub sim releases over time. There has been more submarine games but these below are which matter.
1983, Gato
1985, Silent Service
1987, The Hunt for Red October
1988, Red Storm Rising
1994, Aces of the Deep
1995, Command: Aces of the Deep
1996, Silent Hunter
1997, 688(I) Hunter/Killer
2001, Silent Hunter 2
2001, Sub Command
2005, Dangerous Waters
2005, Silent Hunter 3
2007, Silent Hunter 4
2010, Silent Hunter 5
2017, Cold Waters