SQ21, the sister flight usually goes over London, or thereabouts around 9pm local most evenings (SQ23 no idea). I've watched it on and off for the last month or so and like both posters above the thought that it's journey takes from 18.5 to 19.5hrs depending on winds/routing is truly amazing. It blows my mind that it has (I presume) 200+ passengers plus catering plus luggage plus cargo and fuel reserves for weather diversions etc, c r a z y! A tribute to Airbus on their A350. Apparently Qantas is soon to be commencing LHR-SYD direct flights using the A350-1000 that will be well over 20hrs aloft. I hope they offer thrombosis socks to the passengers whilst boarding :-)