User Story
I am a WWII submarine commander and this game simulates my experience.
A mission always starts at one of our ports and ends when the submarine is destroyed or returns to base. Submarines in this era could run for no more than ten hours underwater at six knots, but on the surface could run at twelve knots. It could dive to no more than 500 feet and had supplies for a 45 day journey.
Life in a submarine consisted of three types of experiences: cruising, attacking and fleeing. The overwhelming amount of time was spent cruising, looking for a target. This could go on for days. On the surface a ship may only be seen if it is closer than six miles, but the noise of a ship could be heard for about twelve. Occasionally we would hear a nearby ship and try to approach and attack. An attack involved an underwater approach and the firing of one or more torpedoes. The sub carried thirty six torpedoes, but could only shoot them one or two at a time. The problem is that most enemy ships were faster on the surface than we were underwater. So if they detected us they could flee or dodge our torpedoes. Moreover, if the ship was a destroyer – destroyers always accompanied capital warships and often groups of transports – if would then pursue us and try to destroy us with depth charges. Destroyers are fast and very maneuverable, so it is very difficult to torpedo one. Evading a destroyer required luck. We could run quietly away, provided we were far enough away when the action starts. At about two knots we could not be heard. Sometimes we would lay on the bottom and just wait, provided the bottom was less than about four hundred feet. A depth charge does not have to be very close to destroy us at greater depths.
The submarine has simple controls. We have a map of our area with our location shown. If we are within range of another vessel, that vessel will also appear on the map. Of course, we do not know where vessels that we are not close to will be. We have a heading, which is the direction we are oriented. This is an angle from 0 to 359. True North is zero, due East is ninety etc. We have several speeds, full, three-quarters, half, one quarter and stopped. These translate into different speeds when we are surfaced or submerged. We may also set the depth of submersion. We may only fire torpedoes when we are at about sixty feet. Our submarine currently has a defective periscope, but our sonar man can tell us the range and bearing of ships that are within range. However, he cannot tell us their heading or speed. He is pretty good about identification though.
Since I am the commander, I am on duty 24/7. Fortunately when cruising I may merely give the command to proceed on a particular course, at a particular speed for some number of hours. My executive officer will interpret my commands by running surfaced. However, if we are within range of any other ship or islands are approaching I will be notified immediately.