Originally Posted by
3stripes
In the UK (where we're both originally from) when acting as pilot flying in a multi crew flight deck, a First Officer can log the flight time as PiC/US if he holds a full type rating (which we both do) and the captain signs his log book at the end of the day.
That may be the case in the UK, but in the US, most airlines consider PIC time as the time that you are in command of the AC. That means he has to sign the aircraft logbook as such.
That being said, tell him to apply and let them decide.