Concorde - Wikipedia, the free encyclopedia:
Concorde flew fast enough that the weight of everyone onboard was temporarily reduced by about 1% when flying east. This was due to centrifugal effects since the airspeed added to the rotation speed of the Earth. Flying west, the weight increased by about 0.3%, because it cancelled out the normal rotation and, with it, the normal centrifugal force and replaced it with a smaller rotation in the opposite direction. Concorde flew high enough that the weight of everyone onboard was reduced by an additional 0.6% due to the increased distance from the centre of the Earth.
Concorde's cruising speed exceeded the top speed of the solar terminator. Concorde was able to overtake or outrun the spin of the earth. On westbound flights it was possible to arrive at a local time earlier than the flight's departure time. On certain early evening transatlantic flights departing from Heathrow or Paris, it was possible to take off just after sunset and catch up with the sun, landing in daylight. This was much publicised by British Airways, who used the slogan "Arrive before you leave."