Directional control after touchdown...

Dudley Henriques wrote:
"Matt Whiting" wrote in message
...
Dudley Henriques wrote:
This brings out the most important point to be made in this entire
thread.
"Let the AIRPLANE tell you what the ACTUAL winds are and fly the approach
and landing doing whatever the AIRPLANE tells you needs to be done for
the wind.
This is cardinal rule 1 for ALL landings and supercedes any and all
forecast and radio transmitted expectation for wind condition and
direction.
Dudley Henriques
Say it again, Dudley! You fly the conditions as they exist, not what you
think they are or wish they were.

Matt

"You fly the conditions as they exist, not what you think they are or wish
they were".
How's that!! :-))
DH



That's a keeper! :-)

Matt

In article om,
says...
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.

Regardless, this is the right move (IMO) - as it's possibly caused by
less crosswind down at RWY level - you use aileron to control the drift,
rudder to keep it pointing in the right direction.

--
Duncan

On May 20, 6:09 pm, Dave Doe wrote:
In article om,
says...





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.

Regardless, this is the right move (IMO) - as it's possibly caused by
less crosswind down at RWY level - you use aileron to control the drift,
rudder to keep it pointing in the right direction.

--
Duncan- Hide quoted text -

- Show quoted text -

Thanks. That's exactly what I was getting at. Obviously, I know this
is true when still in the air, but I was not sure if this rule changed
when rolling down the runway...

--Dan

Dave Doe wrote:
In article om,
says...
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.

Regardless, this is the right move (IMO) - as it's possibly caused by
less crosswind down at RWY level - you use aileron to control the drift,
rudder to keep it pointing in the right direction.


Once you are on the runway, the ailerons aren't going to do much for drift.

Matt

Dan wrote:
On May 20, 6:09 pm, Dave Doe wrote:
In article om,
says...





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.
Regardless, this is the right move (IMO) - as it's possibly caused by
less crosswind down at RWY level - you use aileron to control the drift,
rudder to keep it pointing in the right direction.

--
Duncan- Hide quoted text -

- Show quoted text -

Thanks. That's exactly what I was getting at. Obviously, I know this
is true when still in the air, but I was not sure if this rule changed
when rolling down the runway...

It changes a lot. Drift is controlled in the air by slipping which
requires bank. Since you can't bank while on the ground, the ailerons
aren't going to do much for drift. They help keep weight on the upwind
wheels to provide better traction and they help keep the wind from
flipping you over, they they don't do squat for drift. That is a
function of rudder and tire traction.

Matt

"Newps" wrote in message
. ..


Bill Denton wrote:
Could it be the ground effect differences between low wing and high wing
aircraft that are contributing to this issue?


No, I noticed that right away after I bought my Bonanza. With my 182 it
was second nature to manipulate the aileron for the wind while taxiing.
In the Bo I don't bother as there's no reason to. I simply hold the
yoke so the controls don't get slammed around in the wind. With a high
wing the wing is out there on a longer lever plus the wheel track is a
little narrower.

I am pretty sure that there is also more wind six feet from the graound than
there is three feet from the ground.

Presumably there are plenty of statistics on the subject, although I have no
idea where to look or would would make a good search argument for and
internet search.

Peter

Peter Dohm wrote:




I am pretty sure that there is also more wind six feet from the graound than
there is three feet from the ground.

You're kidding.




Presumably there are plenty of statistics on the subject,


You'll never find that as it isn't true.

In rec.aviation.student B A R R Y wrote:
Most of the non-towered fields I use have either an AWOS or ASOS
(maybe Belfort? G), that updates every minute, but the same caveats
apply about the location of the instrument taking the reading vs. the
runway.

Besides that, the wind can *change* between the time the reading is taken
and the time you flare.

I went up for some crosswind practice the other day, and the winds were
really squirrelly -- changing constantly, and very different at altitude
and on the ground.

Every few minutes, somebody would key the mike to get a wind check from
the local reporting station on the CTAF. Each time, the winds were
noticeably different, both in direction and strength. It was kind of
funny, and, while I paid attention, I didn't count on the information
still being correct while I was landing.

Each landing was different from the one before, and I had to pay attention
to the winds each moment, and react to what they were doing there, not
what they were reported to be.

Which made it a lot of fun, of course.

.... Alan
--
Alan Gerber
PP-ASEL
gerber AT panix DOT com

In article ,
says...
Dave Doe wrote:
In article om,
says...
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.

Regardless, this is the right move (IMO) - as it's possibly caused by
less crosswind down at RWY level - you use aileron to control the drift,
rudder to keep it pointing in the right direction.


Once you are on the runway, the ailerons aren't going to do much for drift.

They are as you touch down on one wheel - which is where I'm comin from
(the OP can't have much weight on the wheels if the plane is still
drifting as he describes - well that's the way I read it).


--
Duncan

Newps wrote:


Peter Dohm wrote:




I am pretty sure that there is also more wind six feet from the
graound than
there is three feet from the ground.

You're kidding.




Presumably there are plenty of statistics on the subject,


You'll never find that as it isn't true.

It absolutely is true. Wind velocity drops dramatically as it
approaches a surface.

Matt