from 1997 to 2001, I flew with brymon airways between newcastle and southampton. in those 4 years I had approximatley 200 flights with them, at least 90% of which were on the flight deck jump seat. in the end I had more hours on a dash 8 flight deck than some of the first officers and learnt more about aviation in that time than in the previous 25 years!
flight deck jump seat rides are absolutley essential for atcos and flight crew in my humble opinion. familiarisation flights are all well and good but when you get to know each other (I mean REALLY get to know each other), then we can get down to asking each other some proper operational questions and finding out the real answers! however, with all the restrictions re security / passes / payment / locked flight deck doors it's nigh on impossible to get up the front any more.
I used to just get on board, show my id pass and ask to sit with the flight crew. those days are l-o-n-g gone which is VERY disappointing.
my sincere thanks to all the flight crew I got to know at brymon - I miss you all a lot