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Some success at last
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rickofudall



Joined: 19 Sep 2009
Posts: 1392
Location: Udall, KS, USA

PostPosted: Tue Nov 15, 2011 8:43 pm    Post subject: Some success at last Reply with quote

After my neighbor offered the observation that I seemed to need an awful lot of rudder to keep the Mk IIIX flying straight on take off I started investigating and found that the vertical stabilizer was off ever so slightly. See picture 1. I removed the rudder trim tab and flew the airplane. You can see from picture 2 that the airplane flew a bit sideways. The Yaw string is about 8" long and I'd guess it is deflected about 2.5" giving a side slip of a little over 18 degrees. 
If you look carefully at picture 3 you can see how much the rudder is deflected to keep the airplane flying straight in level flight. Sorry, I've never tried to take a picture over my shoulder while trying to fly an airplane straight and level.
After the vertical stabilizer was moved to align it straight down the tail boom, I flew it again, still without a rudder trim tab. Under power, there was no change in the results shown in picture 2. Pull the engine back to idle and yaw string flows right down the line on the windscreen and the ball is centered.
Where the improvement really shown was in the power off stall characteristics. Before removing the trim tab, the airplane had a bad break to the left almost immediately at the onset of buffeting and it took rapid application of forward stick and right rudder to break it. Now with the trim tab removed, the airplane flies straight with the engine at idle and my feet off the rudder peddles. The stall is much more like that of my Mk III, no wing drop and recovery only requires releasing the back pressure on the stick.
I still have no idea why P factor is so strong in this airplane. I've checked the engine alignment and it is straight down the centerline of the airplane as best as I can measure it. Because Ken's prop no longer fits after I lowered the engine mount to the factory recommended height, I'm using my prop, adjusted for the difference in the gearbox ratios of Ken's engine (2.62) and mine (4.00).
So, I'm taking heart in the fact that the airplane no longer wants to break into a spin when stalled without power. I did not do a departure stall with it, if the weather is nice again tomorrow, I may work up my courage and give it a try. My airplane would not do a departure stall, it would just hang on the prop until I release back pressure. Somehow I don't think I'll get the same results with this airplane, but I've been wrong before.
Anyway, I think the airplane is much safer, although I can only fly it for about 30 minutes before I get a cramp in my left calf.
Rick Girard

--
Zulu Delta
Mk IIIC
Thanks, Homer GBYM
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John Hauck



Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

PostPosted: Wed Nov 16, 2011 4:31 am    Post subject: Some success at last Reply with quote



I still have no idea why P factor is so strong in this airplane.


Anyway, I think the airplane is much safer, although I can only fly it for about 30 minutes before I get a cramp in my left calf.



Rick Girard



Rick G/Kolbers:

Before I doubled the size of my rudder trim tab my mkIII flew about 1/2 bubble out of trim. Other than bugging me because it was not perfect, the mkIII flew great that way. In fact, I flew the 17,400 mile flight in 1994, that way.

I decided to experiment to correct this problem by offsetting the leading edge of the upper vertical stabilizer. Moved it three times in 1/2" increments. Each time there was insignificant improvement in the adverse yaw.

After the experiment was over, I returned the upper vertical stabilizer to its centered position and doubled the length of the rudder trim tab, from one rib bay to two. That fixed the adverse yaw problem. Now my mkIII flies in yaw trim with my feet off the pedals.

I believe the adverse yaw problem is caused by the way the rotating prop blast hits the tail section. My prop turns counter clockwise when observed from the rear. All the oil that is blown from the oil tank breather hose hits the left side of the upper vertical stabilizer and the top of the left horizontal stabilizer. My rudder trim tab counteracts this force.

That big pusher prop does a lot of weird things to some Kolbs.

john h
mkIII
Titus, Alabama





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John Hauck
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PostPosted: Wed Nov 16, 2011 7:34 am    Post subject: Some success at last Reply with quote

Rick

Keep looking for that cure I don't think this is it. During primary training I was trained to keep the ball centered at all times especially in stall. In less I'm miss interpreting your description I have to believe you were allowing the plane with the trim tab to yaw when going into stall.


I currently have the leading edge of my vertical stabilizer off set by about an inch. I really couldn't tell any difference but it has to help the trim tab do its work. My trim tab is defected about 45 degrees and seems to be about right. I add left rudder under full power climb, right rudder power off and just a bit left in cruise. 


Big high thrust props flying at a high angles of attack produce lots of asymmetrical thrust referred to a P factor. No thrust, no P factor. Your photo was taken from one side so it will naturally look like it is defected. 


Rick Neilsen
Redrive VW Powered MKIIIC

On Wed, Nov 16, 2011 at 9:35 AM, Richard Girard <aslsa.rng(at)gmail.com (aslsa.rng(at)gmail.com)> wrote:
[quote]Thanks, John. My Mk III is completely different from yours apparently. It has almost no trim tab and the tab has almost no bend in it, maybe 10 degrees. The plane needs just a smidgeon of left rudder in climb and the same amount of right rudder in cruise. No comparison to yours and none at all to Ken's X. I was pretty tired when I wrote last night and I got the wrong photo for number 3. Here's the correct photo.
Rick

On Wed, Nov 16, 2011 at 6:29 AM, John Hauck <jhauck(at)elmore.rr.com (jhauck(at)elmore.rr.com)> wrote:

Quote:

 
 


I still have no idea why P factor is so strong in this airplane.  
 


Anyway, I think the airplane is much safer, although I can only fly it for about 30 minutes before I get a cramp in my left calf.

 

Rick Girard
 
 
 
Rick G/Kolbers:
 
Before I doubled the size of my rudder trim tab my mkIII flew about 1/2 bubble out of trim.  Other than bugging me because it was not perfect, the mkIII flew great that way.  In fact, I flew the 17,400 mile flight in 1994, that way.
 
I decided to experiment to correct this problem by offsetting the leading edge of the upper vertical stabilizer.  Moved it three times in 1/2" increments.  Each time there was insignificant improvement in the adverse yaw. 
 
After the experiment was over, I returned the upper vertical stabilizer to its centered position and doubled the length of the rudder trim tab, from one rib bay to two.  That fixed the adverse yaw problem.  Now my mkIII flies in yaw trim with my feet off the pedals.
 
I believe the adverse yaw problem is caused by the way the rotating prop blast hits the tail section.  My prop turns counter clockwise when observed from the rear.  All the oil that is blown from the oil tank breather hose hits the left side of the upper vertical stabilizer and the top of the left horizontal stabilizer.  My rudder trim tab counteracts this force.
 
That big pusher prop does a lot of weird things to some Kolbs.
 
john h
mkIII
Titus, Alabama
 
 

 


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--
Zulu Delta
Mk IIIC
Thanks, Homer GBYM
It isn't necessary to have relatives in Kansas City in order to be unhappy.
  - Groucho Marx



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dan42101(at)yahoo.com
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PostPosted: Wed Nov 16, 2011 8:19 am    Post subject: Some success at last Reply with quote

http://www.av8n.com/how/htm/yaw.html



From: John Hauck <jhauck(at)elmore.rr.com>
To: kolb-list(at)matronics.com
Sent: Wednesday, November 16, 2011 6:29 AM
Subject: RE: Kolb-List: Some success at last





I still have no idea why P factor is so strong in this airplane.


Anyway, I think the airplane is much safer, although I can only fly it for about 30 minutes before I get a cramp in my left calf.



Rick Girard



Rick G/Kolbers:

Before I doubled the size of my rudder trim tab my mkIII flew about 1/2 bubble out of trim. Other than bugging me because it was not perfect, the mkIII flew great that way. In fact, I flew the 17,400 mile flight in 1994, that way.

I decided to experiment to correct this problem by offsetting the leading edge of the upper vertical stabilizer.  Moved it three times in 1/2" increments. Each time there was insignificant improvement in the adverse yaw.

After the experiment was over, I returned the upper vertical stabilizer to its centered position and doubled the length of the rudder trim tab, from one rib bay to two. That fixed the adverse yaw problem. Now my mkIII flies in yaw trim with my feet off the pedals.

I believe the adverse yaw problem is caused by the way the rotating prop blast hits the tail section. My prop turns counter clockwise when observed from the rear. All the oil that is blown from the oil tank breather hose hits the left side of the upper vertical stabilizer and the top of the left horizontal stabilizer. My rudder trim tab counteracts this force.

That big pusher prop does a lot of weird things to some Kolbs.

john h
mkIII
Titus, Alabama




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bransom(at)ucdavis.edu
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PostPosted: Wed Nov 16, 2011 8:42 am    Post subject: Some success at last Reply with quote

Maybe it's normal construction method by now, but when I built my Firestar I made the front attachment for my vertical stabilizer a little wider than necessary — maybe just an 1/8 inch — so that I could shim it either way for desired trim. Seems like it was in the right place from the get go and I never needed to mess with it. ..or I'm just not that discriminating. Wink


I'm not sure I know whether my prop induced yaw is P factor or corkscrew swirl hitting more the top half than bottom half. I believe shimming the engine pitch angle will help either, but mostly the corkscrew effect.


Cheers,
-Ben
Firestar KXP, 1994


From: Danny <dan42101(at)yahoo.com (dan42101(at)yahoo.com)>
Reply-To: <kolb-list(at)matronics.com (kolb-list(at)matronics.com)>
Date: Wed, 16 Nov 2011 08:17:15 -0800
To: "kolb-list(at)matronics.com (kolb-list(at)matronics.com)" <kolb-list(at)matronics.com (kolb-list(at)matronics.com)>
Subject: Re: Some success at last



http://www.av8n.com/how/htm/yaw.html



From: John Hauck <jhauck(at)elmore.rr.com (jhauck(at)elmore.rr.com)>
To: kolb-list(at)matronics.com (kolb-list(at)matronics.com)
Sent: Wednesday, November 16, 2011 6:29 AM
Subject: RE: Some success at last





I still have no idea why P factor is so strong in this airplane.


Anyway, I think the airplane is much safer, although I can only fly it for about 30 minutes before I get a cramp in my left calf.



Rick Girard



Rick G/Kolbers:

Before I doubled the size of my rudder trim tab my mkIII flew about 1/2 bubble out of trim. Other than bugging me because it was not perfect, the mkIII flew great that way. In fact, I flew the 17,400 mile flight in 1994, that way.

I decided to experiment to correct this problem by offsetting the leading edge of the upper vertical stabilizer.  Moved it three times in 1/2" increments. Each time there was insignificant improvement in the adverse yaw.

After the experiment was over, I returned the upper vertical stabilizer to its centered position and doubled the length of the rudder trim tab, from one rib bay to two. That fixed the adverse yaw problem. Now my mkIII flies in yaw trim with my feet off the pedals.

I believe the adverse yaw problem is caused by the way the rotating prop blast hits the tail section. My prop turns counter clockwise when observed from the rear. All the oil that is blown from the oil tank breather hose hits the left side of the upper vertical stabilizer and the top of the left horizontal stabilizer. My rudder trim tab counteracts this force.

That big pusher prop does a lot of weird things to some Kolbs.

john h
mkIII
Titus, Alabama






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PostPosted: Wed Nov 16, 2011 8:50 am    Post subject: Some success at last Reply with quote

At 10:40 PM 11/15/11 -0600, you wrote:

Quote:

........................

Quote:
I still have no idea why P
factor is so strong in this airplane.


Rick,

There are a couple of reasons. You have a high powered, high drag, and
light weight aircraft. When one trims roll to level the wings during
cruise, it counter acts propeller torque and possible P factor due to the
propeller axis not being parallel to the direction of flight. If there is no
trim on the rudder the aircraft will slip during cruise. To reduce this
slip one can reduce the P factor by washering the engine mounts to tilt the
engine front to back until one cannot obtain further improvement as
indicated by the ball or string. After this you are stuck with adding a
trim tab to the rudder to bring the nose around for your normal flight
loading and cruise conditions. Fly at any other condition and P factor and
engine torque will again come back into focus. Of course when you idle the
engine all of these factors disappear.

The reason it is so severe in Kolb aircraft is due to the fact that it takes
more power and torque to fly at a given cruise speed than a sleeker aircraft
of equal weight.

Also there is a flywheel gyroscopic progression effect caused by the
propeller, which indicates that low inertia propellers will reduc this
phenomena.

I am fortunate that I can rotate the reduction unit and off set the thrust
line to the left or right to compensate and dispense with the use of a
rudder trim tab at cruise.

fwiw

Jack B. Hart FF004
Winchester, IN


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Mike Welch



Joined: 13 Feb 2011
Posts: 272

PostPosted: Wed Nov 16, 2011 9:01 am    Post subject: Some success at last Reply with quote

Rick G,

I know you are pretty good at analyzing stuff, and with that MkIIIX you're getting a good work-out, but
have you checked whether the tailfeather cables are EXACTLY the same length (i.e. matched sets)
and are you certain they are tight enough? I recall John H. saying they need to be fairly tight to
maintain good flight characteristics.

Mike Welch


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John Hauck



Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

PostPosted: Wed Nov 16, 2011 10:51 am    Post subject: Some success at last Reply with quote

I recall John H. saying they need to be fairly tight to maintain good
flight characteristics.

Mike Welch

They should be as tight as a banjo string.

john h
mkIII
Titus, Alabama


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PostPosted: Wed Nov 16, 2011 12:02 pm    Post subject: Some success at last Reply with quote



I still have no idea why P factor is so strong in this airplane.
>>>>>>>>>


i don't think that we are dealing with "P" factor,,, i think it is simple prop wash, and it is so bad because the prop is so close to the tail.... and there is no fuselage between the prop and tail.

"P" factor as explained to me when flying a c 150.

the air through the prop in straight and level flight should be perpendicular to the prop. thus the ascending and descending blades of the prop have the same bite in the air. when you are in a climb, the prop disk is no longer perpendicular to the air flow. the descending blade has a greater bite into the air then does the ascending blade. in a C 150 with the prop turning clockwise when looking from the rear, that means, in a climb, the prop blade on the right side has more pull than the blade on the left. turning the plane to the left. SO you have to add right rudder to fly straight.

change the concept to the kolb, on the 912, the prop turns counter clock wise when looking from the rear,

if the air is perpendicular to the prop in level flight, the pull should be the same, but in a climb, the prop blade while on the left should have more bite into the air,,, wanting to yaw the plane to the right,,, which should require left rudder,,,, but in fact as the swirling mass of air hits the rudder, it moves the tail to the right,(nose left) i have to add right rudder, not left as the "P" factor would suggest, the "P" factor counteracts partially the prop swirling factor, but not completely.

this is the simple strait forward explanation,,,, now we have to add into the mix. the air that is being deflected downward from the effect of the wing. that will change the entire dynamic of the problem. to what extent,,, i dont know, that would probably require time in a wind tunnel,

now with the 2 strokes, the prop turns clockwise looking from the rear,,, and the pressure are on the opposite side compared to the 912's, and the rudder inputs and trim requirements are opposite.

boyd young
mkiii utah
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rickofudall



Joined: 19 Sep 2009
Posts: 1392
Location: Udall, KS, USA

PostPosted: Wed Nov 16, 2011 4:18 pm    Post subject: Some success at last Reply with quote

Okay, I'll go through this one question at a time."In less I'm miss interpreting your description I have to believe you were allowing the plane with the trim tab to yaw when going into stall."
Yes, the trim tab was pushing the tail to the right (nose to the left) and causing the aircraft to break hard left when stalled. With the trim tab gone and my feet off the rudder peddles the yaw string and the ball are centered when the engine is at idle. Any power above about 2800 rpm causes the nose to push off to the right. The more power, the more the right yaw requiring left rudder.
"Your photo was taken from one side so it will naturally look like it is defected. "
It looks deflected because it is. It takes about half the left rudder travel to center the ball and the yaw string. It's obvious enough that it can be seen from 200 to 300 feet below, that's why my neighbor was able to make his observation.
"have you checked whether the tailfeather cables are EXACTLY the same length (i.e. matched sets)
and are you certain they are tight enough?" Yep, making new cables was one of the first things I did on this aircraft. They can be strummed like a base viola. One of the few things the OB did was to get the holes in the horizontal stabilizers where the wires attach exactly alike so the left and right
"when you are in a climb, the prop disk is no longer perpendicular to the air flow.  the descending blade has a greater bite into the air then does the ascending blade."
Yep, that's the classic explanation, but both my plane and this X are 582 powered (prop rotation is clockwise viewed from the rear looking forward) and "P" factor is pushing the nose to the right, which means it's the ascending blade doing the pushing. Go figure. My interpretation of this is that the air flowing over the wing is pretty broken up in climb and both sides of the prop above the wing get that crappy inflow. The air coming from under the wing is cleaner so now the ascending blade, on the left has a lower angle of attack and the right side, descending blade is in a stalled condition. It may be wishful thinking, but my Mk III behaves the same way, except that it's not as extreme as it is on the X.
When I flew approach stalls yesterday I did them with my feet pulled back so there's no way I was influencing the airplane's actions in yaw. Both clean and with half flaps the yaw string and ball were centered and stayed that way through the stall. I also did power off glides up to 65 mph and the yaw string and ball were centered then, too, again, with my feet off the rudder peddles.


Rick Girard



On Wed, Nov 16, 2011 at 1:55 PM, b young <byoungplumbing(at)gmail.com (byoungplumbing(at)gmail.com)> wrote:
Quote:
 


I still have no idea why P factor is so strong in this airplane.  
>>>>>>>>>
 
 

i don't think that we are dealing with "P" factor,,,  i think it is simple prop wash, and it is so bad because the prop is so close to the tail.... and there is no fuselage between the prop and tail. 
 
"P" factor as explained to me when flying a c 150.
 
the air through the prop in straight and level flight should be perpendicular to the prop.  thus the ascending and descending blades of the prop have the same bite in the air.   when you are in a climb, the prop disk is no longer perpendicular to the air flow.  the descending blade has a greater bite into the air then does the ascending blade.  in a C 150 with the prop turning clockwise when looking from the rear,  that means, in a climb,  the prop blade on the right side has more pull than the blade on the left.  turning the plane to the left.  SO you have to add right rudder to fly straight.
 
change the concept to the kolb,   on the 912,  the prop turns counter clock wise when looking from the rear,
 
if the air is perpendicular to the prop in level flight,  the pull should be the same,  but in a climb,  the prop blade while on the left should have more bite into the air,,,  wanting to yaw the plane to the right,,,  which should require left rudder,,,,   but in fact as the swirling mass of air hits the rudder, it moves the tail to the right,(nose left)    i have to add right rudder, not left as the "P" factor would suggest,    the "P" factor counteracts partially the prop swirling factor, but not completely.
 
this is the simple strait forward explanation,,,,  now we have to add into the mix. the air that is being deflected downward from the effect of the wing.  that will change the entire dynamic of the problem.   to what extent,,, i dont know, that would probably require time in a wind tunnel, 
 
now with the 2 strokes,  the prop turns clockwise looking from the rear,,,  and the pressure are on the opposite side compared to the 912's,  and the rudder inputs and trim requirements are opposite.
 
boyd young
mkiii utah
Quote:


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--
Zulu Delta
Mk IIIC
Thanks, Homer GBYM
It isn't necessary to have relatives in Kansas City in order to be unhappy.
  - Groucho Marx



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PostPosted: Wed Nov 16, 2011 4:37 pm    Post subject: Some success at last Reply with quote

Quote:
Rick G/Kolbers: Prop blast is hitting the right side of the upper vertical stabilizer, clockwise prop rotation. Takes left pedal under power on the two stroke. Just the opposite on the 912 series. Prop turns counterclockwise, blast hits the left side of the upper vertical stabilizer. Takes right pedal or a proper size rudder trim tab to keep the aircraft trimmed in yaw. My Firestar had the same undesirable habit, but the Ultrastar, prop under the tail boom, did not. Don't think anything has changed with these airplanes until TNK stuck the big nose on the MKIII.
0
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John Hauck
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hauck's holler
Titus, Alabama
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PostPosted: Thu Nov 17, 2011 2:27 am    Post subject: Some success at last Reply with quote

John,
your post is coming through too large to fit on the scheme, large font and blue in colour..
Have you inadvertently changed a setting somewhere?
Anyone else with the same problem or is it me?.

Pat
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PostPosted: Thu Nov 17, 2011 2:43 am    Post subject: Some success at last Reply with quote

<<when you are in a climb, the prop disk is no longer perpendicular to the air flow>>

Really? I know I may be behind on the learning curve but could someone explain this to me.

That means that someone in a vertical climb has the airflow approaching from 90 degrees to the direction of travel which is obviously not so.

Curious

Pat
It seems to me that the airflow is always (apparently) approaching
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Dana



Joined: 13 Dec 2007
Posts: 1047
Location: Connecticut, USA

PostPosted: Thu Nov 17, 2011 3:49 am    Post subject: Some success at last Reply with quote

At 05:40 AM 11/17/2011, Pat Ladd wrote:
Quote:
<<when you are in a climb, the prop disk is no longer perpendicular to the air flow>>

Really? I know I may be behind on the learning curve but could someone explain this to me.

That means that someone in a vertical climb has the airflow approaching from 90 degrees to the direction of travel which is obviously not so.

Pat, this is the usual explanation of P-Factor. If the engine is set so the shaft is parallel to the airflow at cruise (prop disk perpendicular to the airflow; the usual condition), then when you're flying slower (as in climb) and at a greater angle of attack, the shaft is no longer parallel to the airflow, i.e. the prop disk is no longer perpendicular. In this case the difference in blade AOA between the blade going up and the blade going down causes an asymmetric thrust, or P-Factor.

-Dana
--
In general, liberalism consists of A & B getting together to see what they can make C do for poor old D.
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PostPosted: Thu Nov 17, 2011 4:30 am    Post subject: Some success at last Reply with quote

I saw the same as you.

do not archive
      Bill Sullivan

--- On Thu, 11/17/11, Pat Ladd <pj.ladd(at)btinternet.com> wrote:
Quote:

From: Pat Ladd <pj.ladd(at)btinternet.com>
Subject: Re: Some success at last
To: kolb-list(at)matronics.com
Date: Thursday, November 17, 2011, 5:25 AM

John,
your post is coming through too large to fit on the scheme, large font and blue in colour..
Have you inadvertently changed a setting somewhere?
Anyone else with the same problem or is it me?.

Pat
Quote:
www.ow" target="_blank" href="http://www.buildersbooks.com">www.buildersbooofollow" target="_blank" href="http://www.matronics.com/contribution">hllow" target="_blank" href="http://www.matronics.com/Navigator?Kolb-Lis --> http://www.matronics.com/con================



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Mike Welch



Joined: 13 Feb 2011
Posts: 272

PostPosted: Thu Nov 17, 2011 4:44 am    Post subject: Some success at last Reply with quote

Pat,

Yes, I receive (most of) John H's post with really big fonts, lately. I thought he was just just thoughtful for the "poor sight crowd".
(that was a joke) But those 1/2" tall letters do make it easier for me to read....and that's NOT a joke.
What is weird is, 'your emails', and several other guys' emails come in SUPER tiny....I mean really "squint and focus"
tiny. And what's worse, is sometimes they also come in light blue, too. Very hard to read light blue "warning label
sized print".
Obviously, someone has let loose the font gremlins recently.
Mike Welch


On Nov 17, 2011, at 4:25 AM, Pat Ladd wrote:
Quote:
John,
your post is coming through too large to fit on the scheme, large font and blue in colour..
Have you inadvertently changed a setting somewhere?
Anyone else with the same problem or is it me?.

Pat
Quote:


href="http://www.aeroelectric.com">www.aeroelectric.com
href="http://www.buildersbooks.com">www.buildersbooks.com
href="http://www.homebuilthelp.com">www.homebuilthelp.com
href="http://www.matronics.com/contribution">http://www.matronics.com/contribution
href="http://www.matronics.com/Navigator?Kolb-List">http://www.matronics.com/Navigator?Kolb-List
href="http://forums.matronics.com">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/contribution



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John Hauck



Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)

PostPosted: Thu Nov 17, 2011 6:16 am    Post subject: Some success at last Reply with quote

John,

your post is coming through too large to fit on the scheme, large font and blue in colour..

Have you inadvertently changed a setting somewhere?

Anyone else with the same problem or is it me?.



Pat
Quote:
Patrick/Kolbers: I apologize for the inconvenience. However, I haven't changed my Outlook settings, that I know of. That doesn't mean the gremlin didn't change it for me. Do you think visiting porn sites could do that? I'll try and write smaller and blacker. Wink
0
Quote:
1
Quote:
2
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3
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4
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5
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John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama
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Mike Welch



Joined: 13 Feb 2011
Posts: 272

PostPosted: Thu Nov 17, 2011 6:36 am    Post subject: Some success at last Reply with quote

Quote:
Quote:
Do you think visiting porn sites could do that?


john h
Quote:
mkIIITitus, Alabama




John H,
hahahaha......hahahahaha....
Doesn't seem to have affected my posts. Eeecks!!
Mike (still chuckling)

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PostPosted: Thu Nov 17, 2011 7:14 am    Post subject: Some success at last Reply with quote

<<then when you're flying slower (as in climb) and at a greater angle of attack>>

Thanks Dana,

Humm!. Not completely happy with that. If you have enough power to climb and NOT slow up, what happens then? As far as I can see the airflow direction in relation to the plane (what in sailing circles is called the apparent wind) is still directly on the nose. In that case it would appear that it is a matter of airspeed, not attitude. Therefore the P factor should change as you throttle back in the cruise. Does it?

Still curious

Pat
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PostPosted: Thu Nov 17, 2011 8:27 am    Post subject: Some success at last Reply with quote

The answer to yaw problems is to drive a puny airplane. I can fly mine with my feet flat on the floor. Smile(not that I actually do)
P- factor, as in, "I really need to land soon"
BB
do not archive

On Nov 17, 2011, at 10:12 AM, Pat Ladd wrote:
<<then when you're flying slower (as in climb) and at a greater angle of attack>>

Thanks Dana,

Humm!. Not completely happy with that. If you have enough power to climb and NOT slow up, what happens then? As far as I can see the airflow direction in relation to the plane (what in sailing circles is called the apparent wind) is still directly on the nose. In that case it would appear that it is a matter of airspeed, not attitude. Therefore the P factor should change as you throttle back in the cruise. Does it?

Still curious

Pat
Quote:


href="http://www.aeroelectric.com">www.aeroelectric.com
href="http://www.buildersbooks.com">www.buildersbooks.com
href="http://www.homebuilthelp.com">www.homebuilthelp.com
href="http://www.matronics.com/contribution">http://www.matronics.com/contribution
href="http://www.matronics.com/Navigator?Kolb-List">http://www.matronics.com/Navigator?Kolb-List
href="http://forums.matronics.com">http://forums.matronics.com
href="http://www.matronics.com/contribution">http://www.matronics.com/contribution



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