Originally Posted by
Fly-by-Wife
I think you are confusing track with heading. If you align the aircraft so that you are flying the runway heading, a crosswind will indeed drift the aircraft sideways while it is still airborne.
The amount of drift will be proportional to the strength of the x-wind component, the inertia of the aircraft and the length of time that the x-wind has to act on the aircraft.
In certain circumstances this may well be negligible, as you suggest, but with a light aircraft in a strong x-wind it is most assuredly not trivial!
FBW
I most certainly am
not confusing track & heading. A crabbed approach is flown with the heading offset into wind so that the aircraft tracks down the extended runway centreline. You don't want to touch down like that as the side loads can damage the undercarriage so before landing you use the rudder to align the aircraft heading with it's track.
Here's the crucial bit: applying rudder does not change the direction in which the aircraft moves
through the air. The direction of travel through the air will continue to be towards the windward side of the runway, add in the effect of the wind & the aircraft will continue to track down the runway centreline, even if the wings are level. It's an aircraft, not a boat. The rudder does not turn the aircraft, not at 2,000', not at 6".
(OK, if you shove in a bootful of rudder & keep the wings level, an aircraft will gradually, slowly, eventually change direction, but we're talking about the last second or two of flight here. There isn't enough time for the rudder to change the direction of travel at the end of a crabbed approach.)