Here’s a video I took aboard a British Airways 747-400 G-CIVX at London Heathrow Airport. You can see parts of us taxiing to the runway as well as the takeoff. I was slightly concerned while we were taxiing as I was seeing some liquid coming out of the wing that I though might have been fuel. (you can really notice at 0:20, 7:10, 0:52 near the wing tip). Please give me your thoughts on this and let me know what it could be! This was taken from seat 34A and this was flight BA49 from London Heathrow Airport to Seattle-Tacoma International Airport. Also enjoy some of the other traffic around Heathrow including a Lufthansa A321, British Airways A318, A319, A320, Aer Lingus A318, Air Canada 767-300, American Airlines 777-200 and a few others!