Welcome aboard!
Like Elmer said, it is possible to be "too" close. 120 Meters is way too close! BdU says Be Aggressive but you are too much!
120 meters??? might as well afix a bayonet on the bow of your sub and charge in for the kill :rotfl:
I would not shoot under 400 meters and most of my shots are at between 700 and 1,000 meters. At those ranges your margin of error is not too big and even if the ship sees you, there is not much it can do before the torpedo hits.
I think we have all been there in the situtation of no torpedoes left and a crippled ship. Blast that "can not man guns in rough weather" I am the Kaluen and I will say when the crew gets out there!
Makes me so frustrated that I want to do something about it.... like change a configuration file or something (innocent look).
Good luck with your career.