Skip to main content

Southwest Airlines Community

Fast approach in gusty weather...

rstark
Adventurer B
Fast approach in gusty weather... 

From a frequent flier: While landing in gusty winds it looked like we were going way faster than normal. We floated way down the runway and then pounded on the runway after which the pilots slammed on the brakes! Why would this happen?

Without any winds, the aircraft flies at basically 1.3 times the stall speed. (Stall speed is the speed at which  the wings essentialy "quit working" and lift would diminish rapidly.) When you have winds and gusts, we take half of the steady state winds and then add the gust component up to a max of 20 additional knots. That number gets added to our approach speed. Flying "plus 20" looks faster if the winds are mostly crosswinds. With headwinds, they usually average out. When the wing gets down to an altitude of half of its wingspan it enters ground effect. That reduces tons of drag on the plane as it travels through the air. Now, add 20 knots, and you have a plane that wants to float and float and float... At some point you have to stick it on the runway and that appears to be what you experienced. Maybe the Pilot was trying to "flare it on" when in retrospect, he or she could have flown it down to the ground (often yielding a smooth landing). Or, sometimes you can fly final in smooth air and get hit with a big gust that adds lift and makes you float. Either way, brakes only work on the ground so getting the plane stopped is only possible once it has landed. Float a little too far, and that means firmer braking to get the plane stopped.

 

Either way the Pilot played it safe and got the plane on the ground so he or she could get it stopped.

6 Comments