Originally Posted by
1aaa
Thank you for the answers so far. I am considering flying in J so will be all sorted and ready to go for the much needed shower. Will I need to do anything with my passport, or only at arrival in London? Or does security only involve chucking things through X ray scanners?
Your passport is checked after security, along with your boarding pass as you re-board.
SIN arrivals/departures are not separate, so you exit the aircraft, race to the lounge, have a shower and drink, race back to the aircraft, go through security at the gate, and then show your passport/BP at the gate before re-boarding.