I think that this is one of the few things the V-force had right!
First, Co, Radar, Plotter, AEO
If there was a QFI on board, he would be the Captain, irrespective of which seat he was in, but would routinely be addressed by crew position. Similarly, a Phase 5 co-piglet flying in the first pilot's position with the constituted crew would be 'First' and the other pilot 'Co'. But if the 'real' Captain needed to make a command decision, he would call 'Captain to crew' - which would wake everyone up in an unambiguous manner!
Whereas the trucky force was far more cumbersome - whoever sat in the Left Seat was 'Captain' even if he/she wasn't the Aircraft Commander and the 'real' Captain was a QFI sitting in the Right Seat as co-pilot or was in the jump seat. Nothing worse than if a question was posed as "Captain?" "Yes?" "No, sorry, not you, but the other Captain" or similar.
I don't know what the Kipper Fleet did in the air on their multiplicity of intercomms with their back end captains - a situation which the 'no stick = no vote' pilots in the rest of the RAF used to find distinctly odd. Although a mate of mine told of the night when the first pilot had to go around due to low cloud, only to be asked by the back end Captain "Can't you go a little lower next time?". To which he handed over control to the co-pilot, unstrapped went down to the back end amongst the pie munchers and said "All yours then, Captain!". Needless to say, they diverted!
Huggy-fluffy civvy world with 2 pilots and a number of flight attendants - not the same thing at all. As would doubtless be confirmed by a certain ex-FJ pilot on TriShaws who found it distinctly unmilitary and overly familiar to be addressed on first name terms by corporal stewards. Not many did it twice, I gather! Although there were occasions, one understands (usually on the 'Long Dulles'), when stewardesses adressed their captains as God - as in "Oh God, oh God, OH GOD......!!!
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