The SubName.cfg in the Submarine folder has the settings for the Ahead 1/3, etc., by the use of the decimal fractions (my brain seems to tell me that one of those is backwards - Slow??)... those are for surfaced & submerged.
Usually speaking, if you get odd behavior from the crew though, it can be anything from improper attire for your crew (seriously - misspell anything for the crew, and they go blind and cannot comply - strange), to something similar being misconfigured with the equipment, so you do have to double-check everything. In CMN some time ago, I changed something, and then the sub would not move until I submerged, and then it was fine... s7rikeback found that one, but I do not recall what exactly it was... A mind is a terrible thing to allow to grow old...
