posted on Feb, 25 2019 @ 07:01 PM
High crosswinds, and he's got a lot of flap deployed. Bad combination.
The higher coefficient of lift makes for issues with gust response. Also your "upwind" wing and deployed flaps get hit full blast, while the downwind
wing gets partly blanked by the fuselage so you get assymetric lift. Annd if it's gusts instead of steady, they get the blasts of air at different
times, too. The exposed flap upwind acts like a sail creating extra drag and creating yaw, and the upwind wing gets more flow/lift than the downwing
lift, lifting it, and then it starts to turn on you. So you're getting added instability in pitch and yaw at the same time. Big enough gust can cause
a very bad day, especially when down in ground effect (not happening in the video), where the coefficient of lift is even worse.
Usually you see this with general aviation guys, not with guys flying heavies. It's better to come in a little hotter than normal with a shorter
approach and with reduced or no flaps with strong crosswinds. It gives less surface area and lift differential (turbulence and/or instability), and
you spend less time (smaller distance to travel while also a higher velocity) on approach exposed to the wind beating you up and pushing you off the
You'd be amazed how many guys dial in full flap deployment at your local GA airport, though. Usually the inexperienced guys who are fighting it all
the way in. These guys in the video might have been caught by a surprise gust, or were just not experienced enough, but it is surprising to see
someone in commercial air letting themselves get bounced around.