Yes, exactly. And don't worry - it's complicated for everyone in the beginning, especially if you start with manual targeting from the start. I think it's less about trigonometry skills as lack of knowledge how to operate devices like torpedo data computers and whiz wheels designed for submarines. It's not exactly what we are taught in school (charming idea though) 
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= CRY PTO = MITSH VBHIZ OSMWG OECEY MLZTO UMDFV TKORD B
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