Hey ProPilot ...
It seems to me that you've already allowed quite a bit of "leniency” for this chap. The response you have from “EGKK” is absolutely correct – IF you have accurately described the situation, it doesn’t matter about how “new” you are – you DO have a safety issue here; and I would say something yesterday if given the chance. I’d go to the Chief Pilot and be as honest with him/her as you can. I’d tell him/her of your concern about “over-reacting;” that you don’t desire to get anyone in trouble; BUT you ARE concerned for the safety of the operation. Maybe there is a reason for the “attitude” that has a medical basis of some kind. It could be that you might not only ensuring your life and the lives of the rest of the crew and passengers at any given time, you may be saving your Captain’s life – both literally and figuratively. AND, in the unlikely event the Chief Pilot doesn’t think there is anything to be concerned about, at least you’ll have an opportunity to find another job before this one kills you! Figuratively AND literally!
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AirRabbit