Directional control after touchdown...

[Dan[_1_]]

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

[VH-UNR]

you've got the right idea, you want to get the nose gear onto the
runway as soon as possible, for wind like that you can center the
ailerons, you only really need continous input when theres a strong
cross wind. centering the ailerons should counter the drift. use left
toe brake if you feel the aircraft skidding when using rudder input.
the sooner you get the nose gear to the runway the sooner you'll have
directional control

[Thomas Borchert]

Dan,

> Left aileron would be in the _opposite_ direction of the indicated
> crosswind.
>

Well, seems your nose indicates something else, doesn't it?

--
Thomas Borchert (EDDH)

[Matt Whiting]

Dan wrote:
> 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.

It depends on the reason for the drift. If it is because you landed
without being aligned, then I would hold the aileron into the wind and
correct with rudder. If it is because the wind really is from the other
side, then I would immediately correct the aileron position. However,
you would know the latter based on the control inputs required to
maintain alignment on final. You should have no doubt as to the wind
direction prior to touch down. It sounds like the airplane wasn't
aligned with the runway at touch down and you just need more rudder to
get things back on track.

Matt

[john smith]

Dan wrote:
> What are the proper control inputs to correct the situation?

Yoke full aft, full right aileron, left rudder as necessary to maintain
directional control, flaps up.

[Ol Shy & Bashful]

On May 19, 11:26 pm, Dan > wrote:
> 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
My immediate thought was to schedule some more cross wind instruction
with a good instructor! We are not talking about much wind at all.
ATIS wind is not much of a crosswind - 20deg @ 10kts? I'd be inclined
to use less aileron and more rudder if its drifting right into the
wind. I sure as hell wouldn't drop the nosewheel to the runway and try
to force nosewheel steering with the directional control in question!
And for sure I wouldn't try to correct it with any brakes. Keep in
mind, if its light enough to drift, its still light enough on the
wheels they'll lock up and skid real easy with any brakes.
I'd be putting in lots of rudder, easing full aft elevator to keep
weight off the nose gear, and whatever aileron needed to keep wings
level. If that doesn't work, I'd be giving serious consideration to
making an immediate go around to take a 2nd look at what is happening.
Makes more sense than going off into the weeds while obviously being
behind the aircraft?
Soaring Buzzard
Infamous Worldwide Pilot/Instructor

[Kyle Boatright]

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

"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
>

[Dan[_1_]]

On May 20, 6:34 am, john smith > wrote:
> Dan wrote:
> > What are the proper control inputs to correct the situation?
>
> Yoke full aft, full right aileron, left rudder as necessary to maintain
> directional control, flaps up.

OK, so you're saying that based on the situation, I should trust the
ATIS, not the fact that the plane is drifting right? Should the
ailerons _always_ be into the wind regardless of actual aircraft
drift?

How much rudder in one direction or the other can a tricycle gear
light plane take without groundlooping?

I am working on a checkout in this C182 after about 400 hours in
Pipers. Compared to what I am used to, the Cessna ground handling
(especially after touchdown) seems very squirrley. I've had the same
experience with the couple hours I have in 152s and 172s as well.

--Dan

[Bill Denton[_2_]]

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


"Dan" > wrote in message
oups.com...
> On May 20, 6:34 am, john smith > wrote:
>> Dan wrote:
>> > What are the proper control inputs to correct the situation?
>>
>> Yoke full aft, full right aileron, left rudder as necessary to maintain
>> directional control, flaps up.
>
> OK, so you're saying that based on the situation, I should trust the
> ATIS, not the fact that the plane is drifting right? Should the
> ailerons _always_ be into the wind regardless of actual aircraft
> drift?
>
> How much rudder in one direction or the other can a tricycle gear
> light plane take without groundlooping?
>
> I am working on a checkout in this C182 after about 400 hours in
> Pipers. Compared to what I am used to, the Cessna ground handling
> (especially after touchdown) seems very squirrley. I've had the same
> experience with the couple hours I have in 152s and 172s as well.
>
> --Dan
>

[john smith]

Dan wrote:
> On May 20, 6:34 am, john smith > wrote:
>> Dan wrote:
>>> What are the proper control inputs to correct the situation?
>> Yoke full aft, full right aileron, left rudder as necessary to maintain
>> directional control, flaps up.
>
> OK, so you're saying that based on the situation, I should trust the
> ATIS, not the fact that the plane is drifting right? Should the
> ailerons _always_ be into the wind regardless of actual aircraft
> drift?

As a previous poster wrote, ATIS is only a guide. Keep in mind that the
wind is only measured at one place on the airport.

Ailerons should always be properly deflected when taxiing, taking off or
landing. What direction to apply them and how much will depend on the
direction the aircraft is moving and the direction the wind is striking
the aircraft from.

Taxiing with a tailwind is different than taxiing with a headwind or
crosswind. Your instructor should have covered that with you in your
primary training. If they didn't find a new instructor.

The best recommendation is to get some taildragger training with an
experienced taildragger instructor. THAT will really teach you about
proper control position and use in an aircraft.

> How much rudder in one direction or the other can a tricycle gear
> light plane take without groundlooping?

You only apply as much rudder as necessary to maintain control in the
direction you want to go.

[john smith]

> On May 19, 11:26 pm, Dan > wrote:
>> 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.

Dan, a couple other things to consider...

Is there just you and an instructor in the plane?

How big are you and the instructor?

Full fuel, two up front, at 65 kts, your over the numbers speed is too
fast.

Try slowing to 55 - 60 kts over the numbers. Full stall stall speed is
going to be below 45 kts at the lighter weight.
Your are drifting because you are still too light on the wheels.

Does the stall horn go off as the wheels touch the ground?

Do you float down the runway between roundout and touchdown?

You should be maintaining pitch attitude as the aircraft settles by
steadily increasing backpressure on the yoke.

Even as the wheels touch, you continue to steadily pull backpressure and
hold it full aft until your in your parking spot and the engine is shut
down.

[John T]

"Bill Denton" > wrote in message

>
> Could it be the ground effect differences between low wing and high
> wing aircraft that are contributing to this issue?
>
> "Dan" > wrote in message
> oups.com...
>>
>> I am working on a checkout in this C182 after about 400 hours in
>> Pipers. Compared to what I am used to, the Cessna ground handling
>> (especially after touchdown) seems very squirrley. I've had the same
>> experience with the couple hours I have in 152s and 172s as well.

My guess is the difference in nose gear steering. Skylanes use a bungee to
"persuade" the nose gear to turn in a given direction while the typical
Piper nosegear is much more authoritative.

--
John T
http://sage1solutions.com/blogs/TknoFlyer
Reduce spam. Use Sender Policy Framework: http://openspf.org
____________________

[Private]

> "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.

Happy landings,

[B A R R Y]

On Sun, 20 May 2007 20:20:10 GMT, "Private" >
wrote:
>
>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.

Along with all the good stuff that's been mentioned...

If it's a towered field, simply say "Wind Check?" into the mic while
turning final and the tower person will usually give you an instant
reading like "330 @ 9, gusting 14". A double click of the mic button
will confirm reception, no readback or callsign necessary. You
don't need a callsign or any other info when asking, simply "Wind
Check?", they'll know what it means. Both the ask and response are
very quick and don't waste much radio time.

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.

[Dudley Henriques[_2_]]

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

"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
>
> "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
>>
>
>

[Matt Whiting]

Dan wrote:
> On May 20, 6:34 am, john smith > wrote:
>> Dan wrote:
>>> What are the proper control inputs to correct the situation?
>> Yoke full aft, full right aileron, left rudder as necessary to maintain
>> directional control, flaps up.
>
> OK, so you're saying that based on the situation, I should trust the
> ATIS, not the fact that the plane is drifting right? Should the
> ailerons _always_ be into the wind regardless of actual aircraft
> drift?

No, you should know from which side the wind is coming before you ever
touch down. This is very easily detected while on final. And if you
slip to accommodate the crosswind (which is the correct way in this
airplane and almost all others), then you know exactly what is up before
you ever touch down and you also know if the crosswind component is
within the control authority of the airplane.


> How much rudder in one direction or the other can a tricycle gear
> light plane take without groundlooping?

Quite a bit, but if you start to ground loop, then back off! One thing
my primary instructor stress was that you ALWAYS apply whatever control
input is required to get the performance you desire. You don't fly to
some preplanned target. He was not a fly by the numbers pilot and,
while I appreciate the need for that in many high performance airplanes,
his basic philosophy is sound. The conditions are what they are, not
what you planned for or what you wish they were. Fly the conditions,
not some preconceived notion of what they should be.


> I am working on a checkout in this C182 after about 400 hours in
> Pipers. Compared to what I am used to, the Cessna ground handling
> (especially after touchdown) seems very squirrley. I've had the same
> experience with the couple hours I have in 152s and 172s as well.

My Skylane wasn't squirrelly at all. Typically, it is the pilot that is
squirrelly. :-)

Matt

[Matt Whiting]

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

[Matt Whiting]

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

[Dudley Henriques[_2_]]

"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

[Newps]

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.

[Matt Whiting]

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

[Dave Doe]

In article m>,
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

[Dan[_1_]]

On May 20, 6:09 pm, Dave Doe > wrote:
> In article m>,
> 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

[Matt Whiting]

Dave Doe wrote:
> In article m>,
> 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

[Matt Whiting]

Dan wrote:
> On May 20, 6:09 pm, Dave Doe > wrote:
>> In article m>,
>> 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

[Peter Dohm]

"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

[Newps]

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.

[Alan Gerber]

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

[Dave Doe]

In article >,
says...
> Dave Doe wrote:
> > In article m>,
> > 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

[Matt Whiting]

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

[Dylan Smith]

On 2007-05-20, Dan > wrote:
> What are the proper control inputs to correct the situation?

Whatever it takes (including FULL control deflection) to keep it going
straight. If you're starting to weather vane to the right, and are still
weather vaning with the amount of left rudder you have, adding more left
rudder until you start going straight won't make you ground loop. On the
contrary - it'll stop you ground looping to the right!

The C182 has quite an effective rudder (good enough for a 20 kt direct
crosswind, when running just on the main wheels) - don't be shy about
using it!

Never give up - if it looks like you need more control input to keep it
from going off the runway, use it. If you find yourself in a situation
with a sudden very strong crosswind gust, don't forget the wheel brake
also counts for directional control.

--
Yes, the Reply-To email address is valid.
Oolite-Linux: an Elite tribute: http://oolite-linux.berlios.de

[B A R R Y[_2_]]

Alan Gerber wrote:
> 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.

Absolutely!

> Each landing was different from the one before

That's the thing about landings. <G>

[Neil Gould]

Recently, Dan > posted:

> 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.
>
[...]

That is not a lot of wind, and it's certainly not a lot of crosswind (get
out the whiz wheel). The result that you were experiencing has to be from
some other cause... perhaps ATIS was wrong?

So... what I'd suggest is to pay attention to what the plane *is* doing
rather than the theory of what it should be doing based on ATIS.

Neil

[Newps]

Matt Whiting wrote:

> 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.

I better get my digital handheld windmeter recalibrated becxause at 4
feet, the top of the wing on my Bo and six feet, the top of the wing on
a typical Cessna the wind is the same.

[Dan[_1_]]

On May 21, 5:23 am, "Neil Gould" > wrote:
> Recently, Dan > posted:
>
> > 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.
>
> [...]
>
> That is not a lot of wind, and it's certainly not a lot of crosswind (get
> out the whiz wheel). The result that you were experiencing has to be from
> some other cause... perhaps ATIS was wrong?
>
> So... what I'd suggest is to pay attention to what the plane *is* doing
> rather than the theory of what it should be doing based on ATIS.
>
> Neil

OK... However, it does sound like the consensus from the group is that
aileron does nothing to correct drift once the plane has touched
down...

--Dan

[Neil Gould]

Recently, Dan > posted:

> On May 21, 5:23 am, "Neil Gould" > wrote:
>> Recently, Dan > posted:
>>
>>> 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.
>>
>> [...]
>>
>> That is not a lot of wind, and it's certainly not a lot of crosswind
>> (get out the whiz wheel). The result that you were experiencing has
>> to be from some other cause... perhaps ATIS was wrong?
>>
>> So... what I'd suggest is to pay attention to what the plane *is*
>> doing rather than the theory of what it should be doing based on
>> ATIS.
>>
>> Neil
>
> OK... However, it does sound like the consensus from the group is that
> aileron does nothing to correct drift once the plane has touched
> down...
>
I agree, if all wheels are on the ground and the wind is light. OTOH, if
you are touched down on one main, the ailerons are rather important. If
the winds are heavy, they can also keep both of your mains planted on the
runway. IMO, there is no pat answer that supercedes paying attention to
what the plane is doing.

You've gotten some good feedback, and I'd second the suggestion that you
to get some more x-wind experience with an instructor.

Neil

[Kyle Boatright]

"Dan" > wrote in message
oups.com...
> On May 21, 5:23 am, "Neil Gould" > wrote:
>> Recently, Dan > posted:
>>
>> > 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.
>>
>> [...]
>>
>> That is not a lot of wind, and it's certainly not a lot of crosswind (get
>> out the whiz wheel). The result that you were experiencing has to be from
>> some other cause... perhaps ATIS was wrong?
>>
>> So... what I'd suggest is to pay attention to what the plane *is* doing
>> rather than the theory of what it should be doing based on ATIS.
>>
>> Neil
>
> OK... However, it does sound like the consensus from the group is that
> aileron does nothing to correct drift once the plane has touched
> down...
>
> --Dan

Saying ailerons do "nothing" to correct drift after touchdown is probably an
oversimplification. If you land in a banked condition, the ailerons can
help you maintain that condition. Also, even if you've got all of the
wheels on the ground, correct aileron input will reduce the aircraft's
tendency to raise the upwind wing. To a smaller extent, aileron deflection
after touchdown will result in *some* bank angle, because the left and right
gear will have different loading. This is particularly true at higher
speeds, such as right after touchdown.

KB

[Matt Barrow[_4_]]

"Newps" > wrote in message
. ..
>
>
> Matt Whiting wrote:
>
>>>
>>> You'll never find that as it isn't true.
>>
>>
>> It absolutely is true. Wind velocity drops dramatically as it approaches
>> a surface.
>
> I better get my digital handheld windmeter recalibrated becxause at 4
> feet, the top of the wing on my Bo and six feet, the top of the wing on a
> typical Cessna the wind is the same.

I'm sure Whiting will come back that there's 0.05 MPH difference and that
difference should be taken into account.

[Maxwell]

"Dan" > wrote in message
oups.com...
> On May 20, 6:34 am, john smith > wrote:
>> Dan wrote:
>
> I am working on a checkout in this C182 after about 400 hours in
> Pipers. Compared to what I am used to, the Cessna ground handling
> (especially after touchdown) seems very squirrley. I've had the same
> experience with the couple hours I have in 152s and 172s as well.
>

Pipers will always feel much more "sure footed" compared to Cessnas, it's
all in the landing gear. Walk up to both aircraft when they are untied and
try rocking the wings. Big difference. The narrow stance and spring steel
landing gear is a completely different ballgame.

The Piper will feel more agile on a nice paved runway, but it's hard to beat
the ride of a Cessna when the surface starts getting rough. Just boils down
to personal preference and where you fly most I guess.

[Matt Whiting]

Matt Barrow wrote:
> "Newps" > wrote in message
> . ..
>>
>> Matt Whiting wrote:
>>
>>>> You'll never find that as it isn't true.
>>>
>>> It absolutely is true. Wind velocity drops dramatically as it approaches
>>> a surface.
>> I better get my digital handheld windmeter recalibrated becxause at 4
>> feet, the top of the wing on my Bo and six feet, the top of the wing on a
>> typical Cessna the wind is the same.
>
> I'm sure Whiting will come back that there's 0.05 MPH difference and that
> difference should be taken into account.
>
>
>
Plonk.

[Matt Whiting]

Newps wrote:
>
>
> Matt Whiting wrote:
>
>> 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.
>
> I better get my digital handheld windmeter recalibrated becxause at 4
> feet, the top of the wing on my Bo and six feet, the top of the wing on
> a typical Cessna the wind is the same.

I would say so. The following article has a graph shows the
relationship on average between wind speed and height. The difference
between the wind at 1m (about the average height of your Bo wing) and at
2m (about the average height of a 182 wing) is about 10%.

http://www.rpc.com.au/products/windturbines/wind_faq.html

Not a huge difference, but not no difference either.

Matt

[Newps]

Matt Whiting wrote:

>
> I would say so. The following article has a graph shows the
> relationship on average between wind speed and height. The difference
> between the wind at 1m (about the average height of your Bo wing) and at
> 2m (about the average height of a 182 wing) is about 10%.

My Bo wing is 4'2" at the tip. I know that because I installed a
furnace in my hangar last month. The code calls for the furnace to be a
minimum 10 feet above the wing. I'm 6'2" and coud not walk under the
wing of my 182 as it sat on its big tires. So I would say the top of
the wing tip there would be at most 6'6". Even according to your
generalized graph an 18 meter difference in height brings a 5 kph
difference in windspeed, the difference between about two feet is
trivial and certainly not a factor at all for the subject at hand which
was stability of the airplane because one is a high wing and one is a
low wing.

[Matt Whiting]

Newps wrote:
>
>
> Matt Whiting wrote:
>
>>
>> I would say so. The following article has a graph shows the
>> relationship on average between wind speed and height. The difference
>> between the wind at 1m (about the average height of your Bo wing) and
>> at 2m (about the average height of a 182 wing) is about 10%.
>
> My Bo wing is 4'2" at the tip. I know that because I installed a
> furnace in my hangar last month. The code calls for the furnace to be a
> minimum 10 feet above the wing. I'm 6'2" and coud not walk under the
> wing of my 182 as it sat on its big tires. So I would say the top of
> the wing tip there would be at most 6'6". Even according to your
> generalized graph an 18 meter difference in height brings a 5 kph
> difference in windspeed, the difference between about two feet is
> trivial and certainly not a factor at all for the subject at hand which
> was stability of the airplane because one is a high wing and one is a
> low wing.


That is why I said average height of the Bo wing. Most Bonanzas I've
seen have a fair bit of dihedral and the wing isn't anywhere near 4'2"
at the root. I don't know what the average height is, but is sure isn't
4'2".

I don't see how you get a 5 kph difference with 18m altitude difference.
The chart expresses the difference as a factor relative to 1 as it
can't give an absolute wind velocity difference without knowing the base
velocity at 1m which is where the chart starts.

It states that the relationship is to the 1/7th power of the altitude.
Since it takes 1m as the reference altitude for a wind increase factor
of 1.0, an altitude of 18m has an increase factor of 18 to the 1/7th
power. This is 1.51 which indicates that the wind at 18m is 51% faster
than at 1m. Comparing 1m to 2m which is approximately correct to
compare a Bo wing to 182 wing, the increase factor is 2 to the 1/7th
power which is 1.1. Thus the wind velocity at 2m is 10% greater than at
1m. So, if the wind at 1m is 20 MPH then the wind at 2m would be
expected to be 22 MPH. If the wind at 1m is 40 MPH it would be expected
to be 44 at 2m.

As I said, 10% may or may not be significant in any particular
situation, but to say that the wind doesn't vary with altitude above the
ground as you claimed initially is simply false. I realize that you
never admit you are wrong and won't this time, but that doesn't change
the fact that you are wrong and it doesn't change the physics of wind
flow at various altitudes above the ground.


Matt

[Neil Gould]

Recently, Matt Whiting > posted:
>
> I don't see how you get a 5 kph difference with 18m altitude
> difference. The chart expresses the difference as a factor relative
> to 1 as it can't give an absolute wind velocity difference without
> knowing the base velocity at 1m which is where the chart starts.
>
[...]

The conditions in the original post is that the winds were 10 kts.
*reported by ATIS*. I don't know how one would translate that into wind
speed at the point of touchdown with any accuracy, but it's a safe bet
that the height of the wing doesn't much matter in this scenario. One can
be factually correct, yet irrelevant.

Neil

[Orval Fairbairn]

In article >,
"Neil Gould" > wrote:

> Recently, Matt Whiting > posted:
> >
> > I don't see how you get a 5 kph difference with 18m altitude
> > difference. The chart expresses the difference as a factor relative
> > to 1 as it can't give an absolute wind velocity difference without
> > knowing the base velocity at 1m which is where the chart starts.
> >
> [...]
>
> The conditions in the original post is that the winds were 10 kts.
> *reported by ATIS*. I don't know how one would translate that into wind
> speed at the point of touchdown with any accuracy, but it's a safe bet
> that the height of the wing doesn't much matter in this scenario. One can
> be factually correct, yet irrelevant.
>
> Neil

It all boils down to:

1. ATIS is only a guide about landing conditions.

2. Use every control available to correct for drift and to keep the
plane straight on landing.

3. Use flaps as necessary (you may not want flaps with high crosswinds).

4. You, the pilot, are responsible for controlling the plane until it is
parked and the engine shut down -- not the air traffic controller, not
the weather observer, not the FBO.

[Newps]

Matt Whiting wrote:


>
>
> That is why I said average height of the Bo wing. Most Bonanzas I've
> seen have a fair bit of dihedral and the wing isn't anywhere near 4'2"
> at the root. I don't know what the average height is, but is sure isn't
> 4'2".

Cessna's have dihedral too. May not be exactly the same but it's there.


>
> I don't see how you get a 5 kph difference with 18m altitude difference.


Did I read that wrong? The chart said the wind went from 15 kmh to 20 kmh.




>
> It states that the relationship is to the 1/7th power of the altitude.
> Since it takes 1m as the reference altitude for a wind increase factor
> of 1.0, an altitude of 18m has an increase factor of 18 to the 1/7th
> power. This is 1.51 which indicates that the wind at 18m is 51% faster
> than at 1m. Comparing 1m to 2m which is approximately correct to
> compare a Bo wing to 182 wing, the increase factor is 2 to the 1/7th
> power which is 1.1. Thus the wind velocity at 2m is 10% greater than at
> 1m. So, if the wind at 1m is 20 MPH then the wind at 2m would be
> expected to be 22 MPH. If the wind at 1m is 40 MPH it would be expected
> to be 44 at 2m.

That's a lot of words to prove that the difference is irrelevant for the
purpose of this discussion. No way anybody tells the difference from 20
- 22 mph or 40 - 44 mph.

[Matt Whiting]

Newps wrote:
>
> Cessna's have dihedral too. May not be exactly the same but it's there.

Yes, but very little. High-wings have more inherent stability since the
CG is below the CP.


>> I don't see how you get a 5 kph difference with 18m altitude difference.
>
>
> Did I read that wrong? The chart said the wind went from 15 kmh to 20 kmh.

That was a representative example, but didn't apply as we are taking
from about 1m to about 2m, not from 2m to 18m. It is the general
formula that I was looking at which can be used for any wind speed and
altitude difference of interest.


>> It states that the relationship is to the 1/7th power of the altitude.
>> Since it takes 1m as the reference altitude for a wind increase factor
>> of 1.0, an altitude of 18m has an increase factor of 18 to the 1/7th
>> power. This is 1.51 which indicates that the wind at 18m is 51%
>> faster than at 1m. Comparing 1m to 2m which is approximately correct
>> to compare a Bo wing to 182 wing, the increase factor is 2 to the
>> 1/7th power which is 1.1. Thus the wind velocity at 2m is 10% greater
>> than at 1m. So, if the wind at 1m is 20 MPH then the wind at 2m would
>> be expected to be 22 MPH. If the wind at 1m is 40 MPH it would be
>> expected to be 44 at 2m.
>
> That's a lot of words to prove that the difference is irrelevant for the
> purpose of this discussion. No way anybody tells the difference from 20
> - 22 mph or 40 - 44 mph.

4 MPH is the difference between stalling at not stalling if you are
already flying only 2 MPH above the stall.

Whether that is relevant depends on the circumstances, no doubt. I
never said anything different. I'm simply correcting your statement
that wind speed is constant with height above the ground - which it isn't.

Having a 10% higher headwind when touchdown in a 182 vs. a Bo or Piper
is significant with respect to landing and takeoff distance. Check your
POH if you don't think a 10% difference in wind makes a performance
difference.

Matt