The only publicly available submarine periscope training application focused on "eyes only" skills. Suitable for new submariners or those refining their skills. Features: - Seven target types: Arleigh Burke, Zumwalt, QM2, Daring class, Sigma, 052D, and Gorshkov - Four difficulty levels for the ATB / AOB game mode - Up to three targets for the Passive Range and Look Interval mode - Night mode - Distance Of Track calculations - Duration Of Attack calculations - Guided tutorials for every game mode and configuration Any feedback, customisation requests, bug reports or general comments are all welcome.