Having just brought my niece aged 8 to the departure gate for her solo return to the UK from the US, I've been thinking about unaccompanied minors on (long haul) flights.
She was not the only one to be ushered onto the plane before the other passengers and after first class and premium economy. I waited until the words "departed" appeared under the flight # before I left the airport. And I checked with the airport personnel. Since she appeared completely unfazed by the trip over to the US, so she seemed on the way back. The flight is just long and boring, she said.
Anecdotal evidence from recent dinner-table conversations on the subject opines that Americans are more cautious after 9/11 about putting unaccompanied children on flights than Europeans. Its certainly easier to put children on direct flights. Let's see what she has to say about this one.