Sorry to spoil the flow here, but Yes, I have.
I'm certainly making nothing up here. I asked, in flight, if the pilots would mind me visiting after we landed at our destination. I mentioned that I hold a PPL and left it at that.
20 minutes later a different flight attendant, presumably the number 1, came to my seat and almost whispered to me that the Captain was willing to allow me a visit. In the end I got a jump seat landing.
The airline was a British carrier, and the flight attendant told me I was the first person she had seen allowed on the flight deck since 11.09.
The Captains justification was along the lines of "I've been flying for 30 years...."
2 very nice blokes going the extra mile for a wannabe. Let me assure you all, it made my holiday.
All I can say is, ask, what harm can it do?
And for the racial profilers out there, I'm a white English, 18 year old, male.