I'm getting confused with the number of job roles which invlove 'Observation'. I get the OP Assistant role - attached to all artillery gun batteries for identifying targets and calling in fire? This can be done in both the para and commando role, after completion of the respective All Arms course. How does a Naval Gunfire Observer operate then? Obviously it involves targeting with regard to naval guns, but are they part of the Royal Artillery and operate independantly, or do they serve with Infantry battalions? Also, why can an OP Ack not fulfill this role? Sorry for what may seem like a bone question. Cheers chaps.