Radar Uses???

[Kirk]

Hey all. Me again. Being never on a sub I was wondering when does a submarine use its radar? I know or have read that it can give away its possition but if you are looking for a surface contact is it common to use radar to get an idea on bearing? Oh! If radar is not used what other ways of locating a target. You know he/she is out there but not sure where. Is there a search pattern that subs use to search? Any ideas are thankful. Cya.