Well 4 me as P1 its three in reverse oder
3rd: 1st solo - that realisation whilst flying downwind that you are the only person who can land the thing.
2nd: UAS low level flying down Welsh valleys, looking up as walkers went by, and wondering how to get the chute open quick enough if it all went pear shape.
1st: 1st solo aerobatics - just as I started to pull up into my 1st loop
But best pax experience was in a Hawk, out of RAF Brawdy, on an hour long sortie dropping bombs on and machine gunning a Welsh mountain range from 100ft whilst doing 400+knts & pulling 6g turns - amazing.