World War 2 submarine simulator by
Microprose, released in 1990. Set in the
Pacific theatre, the player took control of a variety of submarines for the
American navy, and wrought havoc on
Japanese shipping.
A variety of training and single engagement scenarios were available, but by far the most entertaining and enthralling aspect was the career option.
The player could choose a starting date (from December 7th, 1941) and a class of submarine from a wide selection (my personal claim to fame was taking an old S-Class submairne, World War 1 vintage, through the entire war, constantly turning down offers of newer vessels). Finally, a home port and patrol area could be chosen.
From there, the player would navigate on a map of the South Pacific. Small popups would inform the player of events, such as victories, losses and invasions and soforth, giving a real sense of participating in the ongoing war. Unfortunately, the player didn't seem to have any influence on the course of history - I destroyed several troopships heading for the Philippines near the beginning of the war but the islands still fell. Which brings up one of the interesting aspects: the Manila sub base would fall soon after the war started, but gradually new bases would be built in Australia, Indonesia and Midway, together with new choices of patrol zones.
Graphically, the game was stunning for the time. All the ships were digitized images, and could be identified using an on-screen book. Unlike the original game, though, you could never see land. Firing torpedoes prompted a cool animation. You could stand on the bridge, and fire the deck gun (if you were so equipped) at enemy ships, which would explode with digitized sound effects (all of which could play even without a Sound Blaster) and lots of smoke and fire.
The game was also extremely tense, with the pings of destroyers overhead getting gradually louder, while you attempt to creep away, releasing oil and debris to convince the enemy that their depth charges have ruptured your hull.
IMHO, Silent Service 2 remains the definitive World War 2 submarine simulator, together with the others of its day, Das Boot and Wolfpack. Nothing since has matched its variety, depth (pun intended, why not!) and lastability. Clear the bridge! Dive! Dive! Dive!