Directional control after touchdown...
Private wrote:
"Dan" wrote in message
ps.com...
I've got a question for the group. Suppose you find yourself in the
following situation:
You are flying a C182, landing on runway 22. The ATIS lists the winds
as 240 at 10. The windsock is not visible.
You approach at a normal airspeed, full flaps, coming over the numbers
at 65 kts. The mains touchdown, followed by the nosegear. Slight
right aileron is being maintained into the wind. Everything is
aligned properly and on the centerline at touchdown.
After touchdown the plane starts to drift to the right side of the
runway. You try to correct by pointing the nose back to the
centerline with left rudder. The nose seems to be pointed left, but
the plane is still drifting right. It feels like any more left rudder
could result in bad skidding and/or a ground loop.
What are the proper control inputs to correct the situation?
Left aileron would be in the _opposite_ direction of the indicated
crosswind. Increasing back pressure would make the nosewheel even
less effective.
--Dan
"Kyle Boatright" wrote in message
. ..
This simply illustrates why you can't trust ATIS to give you anything more
than a general sense of the conditions you might encounter. Winds change.
ATIS stations sometimes see different wind conditions than the touchdown
point, due to obstacles and wind direction.
With an ATIS reading of a 20 degree off-centerline, and 10 knots of wind,
I would fly a normal approach and make the corrections necessary to keep
the airplane pointed straight down the runway with no drift during the
flare and landing. I would not pre-suppose anything.
On the other hand, if ATIS was indicating a 90 degree crosswind at 10
knots, and the smoke from chimneys, or waves on a nearby lake, or the
windsock confirmed that information, I would *assume* that I had a
noticeable crosswind to deal with, and would be mentally prepared for
it...
BUT, I'd still wait until final approach to crank in gross corrections to
correct drift, and would apply whatever corrections were necessary in the
flare to keep the airplane aligned and kill any drift.
Bottom line.. ATIS gives you an indication of what the winds were at one
point on the airfield at a given time. The conditions at your touchdown
spot may be different.
KB
I agree with the other good responses in this thread and would only add that
the ATIS is a periodic and not real time report that could IMHE be 1 or more
hours old. I always want to confirm the ATIS by seeing the windsock and
monitoring crab and drift on downwind, base and especially on final.
A wind sock is nice, but entirely optional. If you can't peg the wind
pretty well while flying final, then you need more instruction and more
practice.
Matt
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