Some people are very surprised that some people (not everyone!) who are not crew can still be the cockpit during flight. Why is that so strange? Let’s go back to basics. We are trying to stop the bad guys. I don’t know who the bad guys are but I know it’s not my immediate family or my friends. I also know my colleagues pretty well. So I do not have problem with people who might be described as passengers in the flight deck. What I do have a problem with are the pathetic rules imposed in the name of security in the UK. For example, as along as I don’t have a yoghurt or a pointy stick I can get airside in Britain and take a fully fuelled plane full of passengers anywhere I wish. Not at many airports in Spain or Italy though. They don’t really care what I’m carrying but they do want to know I’m a member of the crew and expect me to be there at a certain time. Also, the UK’s post 9/11 reaction was to prohibit aircraft from overflying nuclear power stations. To make sure that could be done, they published the precise location of each one. That would save a lot of FMS programming! Unfortunately ridiculous, ill-considered rules are shoved into Ops manual by myopic clowns in the UK CAA and people believe that this serves some purpose. I’d suggest that the people who need to get a grip are those who think these rules have any value whatsoever.
As for the OP’s initial question; unless you know the crew very well, PAX in the flighdeck is permitted in OPs manual, the flight is it not on a UK or Irish airline, the flight is not to or from the UK or USA and a variety of other hoops and hurdles are cleared, access is most unlikely.
PM
ps. It entirely legitimate to point out dreadful flaws in security. The CAA winge and whine about not discussing security in public but miserably fail to close the gaping hole in their security procedures imposed on us that are meant to be for the good of all. Let’s have proper security and not the box ticking or the pathetic pantomime that is expensively performed at every airport every day.