The game supplied two mini-game scenarios and two full campaign scenarios. Duration for the two mini-games were 12 and 20 turns each. Duration for the full campaigns were 252 and 122 turns. In Grigsby's prior games, the computer kept track of the number of torpedoes carried on each ship and submarine. But the need to keep track of so many other variables in "North Atlantic '86" necessitated deletion of those counters. Instead each ship had a fixed probability of exhausting its stock of torpedoes each time it fired. This meant, for example, that a submarine might run out of torpedoes after its first attack.