Those IJN (and American & German) AI subs are basically surface vessels, set to Type=17, which in Stock is "Elite Destroyer Escort". That way, they are aggressive when encountering enemy assets, and will charge their position with guns and torpedo tubes a-blazing. They will alter their speed and direction as dictated by the AI_Ship internal settings in the sim file and executable for the game, but they will not submerge, and if they do, they will "stop". You cannot have them on a given course that you have set with waypoints, and have them submerge. They will attempt to, and they will get a pinch lower in the water, but they will then slow down, and if the weather is rough, and the waves up, they might fully submerge - but when they do that, they are actually sinking. The Ko is a different kind of bird. I have not looked at its dat versus sim yet, but I do know that it will submerge itself when its speed increases, such that if you encounter it in the game, it will come at you for an attempt at a 90° attack on your "estimated" position. As it speeds up for that, it is almost like its shape pushes it under water, but it is able to continue at the speed the AI_Ship dictates for attack / run-away. If it keeps attacking, it will eventually sink itself also. My one thought on that a while ago was that it is running on electric all of the time off of its batteries, and as such, that might allow it to continue, I don't know...
These and other issues with the subs will be looked into though for FotRSU. If you initially set one of the current Type=17 AI subs in FotRSU to say -18 or so, intending it to be at PD, it will do so, but it will not motor about there. If you change it's Type= to 200 for a submarine, it will still sit there usually, because of the way it was built and then altered to be an AI surface vessel. If you instead take the original playable submarine, and clone it and make it into an AI sub, it will motor about. I do have a JyunsenB and the US Fleetboat done up that way, and with the torpguns on them, they will shoot torpedoes at you or any other enemy vessel (or airplane). One bad thing about those as they are now, is that they are "visible" to surface vessels, which will then shoot at them with their cannons, and attempt to avoid them, well outside the 'normal' range of torpedo launching for the sub...
There are still several things in line ahead of getting back into attempting to add the submerged AI subs as an add-in to FotRSU, but when I do, I'll keep you in mind, and see what changes we make for that. In the meantime, look in the Sea folder for the current AI subs, and in the Submarine folder for the AI_SubName_sub folders for the submerged ones, as they stand now. The submerged ones are NOT a finished product yet, and the surfaced ones will all likely be altered some. Also, do remember that keltos01 created the IJN subs, which were then edited by s7rikeback & CapnScurvy to function as AI assets in FotRSU. I then took their work to create the submerged ones that don't work quite right yet...
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