That's extraordinarily fast, and in fact, the plane reportedly landed early, a nice perk for everyone on board. But, at the same time, the aircraft was likely cruising at a typical speed for a commercial jet—and it definitely wasn't going 801 mph through the air up at 35,000 feet. That's because there's a big difference between a plane's airspeed and a plane's ground speed. In this case, the plane, traveling from Los Angeles to London, was propelled by incredibly strong tailwinds, thanks to the jet stream. So it was moving fast compared to the ground, but at a normal speed compared to the air current it was in.