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Victor 1+ Report
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jbhart(at)onlyinternet.ne
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PostPosted: Sun Jul 12, 2009 5:54 pm    Post subject: Victor 1+ Report Reply with quote

FireFlyers & Kolbers,

I had planned to fly the Victor 1+ all summer and then take it off and mount
the MZ 34. But since the Victor quit, I decided to take it off and set it
aside as I believe I can get back in the air quicker my mounting the MZ 34.
And I will repair the Victor 1+ this winter.

Went over to the airport this morning, and started to remove the engine.
When I took the exhaust system off, I believe I discovered the problem.
Inside the exhaust manifold ball I found several little metal balls made
from small strips. They were magnetic. What I believe happened is that the
upper piston ring lost it's locator pin and the ring rotated about the
piston until the free end was chopped off in the intake port. Could not
tell anything from the plugs as they were completely black from running a
rich mixture for the last bit. There was little to no build up on the
plugs.

Before removing the engine, I weighed the fueslage, and then I stripped off
everything that had to do with the Victor 1+. At first it was tough because
it was like removing an old friend (it has been pushing me around for eight
years or 520 flights) and knowing that you are not going to be putting it
back. I asked for help at the FBO to lift the engine off. After mounting
the MZ 34 and hanging the propeller in place, I weighted again. The weight
difference was 44 pounds. When I get the correct propeller bolts and mount
directly to the MZ 34 hub, I believe I can get off another pound.

Still have lots to do to get back in the air.

Jack B. Hart FF004
Winchester, IN


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herbgh(at)nctc.com
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PostPosted: Sun Jul 12, 2009 6:16 pm    Post subject: Victor 1+ Report Reply with quote

44 lbs Jack?? Is that a typo? Herb
At 09:52 PM 7/12/2009, you wrote:
Quote:


FireFlyers & Kolbers,

I had planned to fly the Victor 1+ all summer and then take it off and mount
the MZ 34. But since the Victor quit, I decided to take it off and set it
aside as I believe I can get back in the air quicker my mounting the MZ 34.
And I will repair the Victor 1+ this winter.

Went over to the airport this morning, and started to remove the engine.
When I took the exhaust system off, I believe I discovered the problem.
Inside the exhaust manifold ball I found several little metal balls made
from small strips. They were magnetic. What I believe happened is that the
upper piston ring lost it's locator pin and the ring rotated about the
piston until the free end was chopped off in the intake port. Could not
tell anything from the plugs as they were completely black from running a
rich mixture for the last bit. There was little to no build up on the
plugs.

Before removing the engine, I weighed the fueslage, and then I stripped off
everything that had to do with the Victor 1+. At first it was tough because
it was like removing an old friend (it has been pushing me around for eight
years or 520 flights) and knowing that you are not going to be putting it
back. I asked for help at the FBO to lift the engine off. After mounting
the MZ 34 and hanging the propeller in place, I weighted again. The weight
difference was 44 pounds. When I get the correct propeller bolts and mount
directly to the MZ 34 hub, I believe I can get off another pound.

Still have lots to do to get back in the air.

Jack B. Hart FF004
Winchester, IN

Checked by AVG - www.avg.com
07/12/09 08:20:00


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ulflyer(at)verizon.net
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PostPosted: Sun Jul 12, 2009 6:55 pm    Post subject: Victor 1+ Report Reply with quote

How many hours did you have on the Victor before it went South (so to speak).
jerb


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jbhart(at)onlyinternet.ne
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PostPosted: Sun Jul 12, 2009 7:13 pm    Post subject: Victor 1+ Report Reply with quote

At 09:10 PM 7/12/09 -0500, you wrote:
Quote:


44 lbs Jack?? Is that a typo? Herb


Herb,

No, it means the FireFly empty weight should be some where around 210
pounds.

Jack B. Hart FF004
Winchester, IN


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jbhart(at)onlyinternet.ne
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PostPosted: Sun Jul 12, 2009 7:13 pm    Post subject: Victor 1+ Report Reply with quote

At 07:54 PM 7/12/09 -0700, you wrote:
Quote:


How many hours did you have on the Victor before it went South (so to speak).


Jerb,

186 flight hours.

Jack B. Hart FF004
Winchester, IN


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herbgh(at)nctc.com
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PostPosted: Sun Jul 12, 2009 8:08 pm    Post subject: Victor 1+ Report Reply with quote

Jack

Empty wt with the 447? Herb


At 11:08 PM 7/12/2009, you wrote:
Quote:


At 09:10 PM 7/12/09 -0500, you wrote:
>
>
>44 lbs Jack?? Is that a typo? Herb
>

Herb,

No, it means the FireFly empty weight should be some where around 210
pounds.

Jack B. Hart FF004
Winchester, IN


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jbhart(at)onlyinternet.ne
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PostPosted: Mon Jul 13, 2009 5:52 am    Post subject: Victor 1+ Report Reply with quote

At 11:03 PM 7/12/09 -0500, you wrote:
Quote:


Jack

Empty wt with the 447? Herb


Herb,

Engine 447 Victor MZ 34

Displacement 436 382 313

FF Empty Wt 248 252 210+ est

I am bulkhead mounting the engine free air with no pull starter, up side
down off the rear of the root tube. No propeller spacer is required. By
doing this I can rotate the reducer to move the propeller up and the left to
keep the FireFly from slipping at cruise. Also it puts the pumper
carburetor on the left side so that I can flip it over which points the low
and high speed adjustment screw toward the front. I hope to use Richard
Pike's mechanical system idea to be able to adjust the air fuel mixture from
the cockpit.

Jack B. Hart FF004
Winchester, IN


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herbgh(at)nctc.com
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PostPosted: Mon Jul 13, 2009 6:17 am    Post subject: Victor 1+ Report Reply with quote

Jack

This moves the engine back a bit to solve a potential cg problem? Herb
At 09:54 AM 7/13/2009, you wrote:
Quote:


At 11:03 PM 7/12/09 -0500, you wrote:
>
>
>Jack
>
> Empty wt with the 447? Herb
>

Herb,

Engine 447 Victor MZ 34

Displacement 436 382 313

FF Empty Wt 248 252 210+ est

I am bulkhead mounting the engine free air with no pull starter, up side
down off the rear of the root tube. No propeller spacer is required. By
doing this I can rotate the reducer to move the propeller up and the left to
keep the FireFly from slipping at cruise. Also it puts the pumper
carburetor on the left side so that I can flip it over which points the low
and high speed adjustment screw toward the front. I hope to use Richard
Pike's mechanical system idea to be able to adjust the air fuel mixture from
the cockpit.

Jack B. Hart FF004
Winchester, IN

Checked by AVG - www.avg.com
07/12/09 17:56:00


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jbhart(at)onlyinternet.ne
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PostPosted: Mon Jul 13, 2009 8:12 am    Post subject: Victor 1+ Report Reply with quote

At 09:17 AM 7/13/09 -0500, you wrote:
Quote:


Jack

This moves the engine back a bit to solve a potential cg problem? Herb


Herb,

To move the cg forward a little, I will cut the propeller to 60 inches,
remove the thick washer that goes between the IVO propeller blades and the
spacer and mount the muffler as far forward as I can. I used bulkhead
vibration isolators in conjunction with the standard FireFly engine mounting
plate isolators. If I have to, I can discard these isolators and move the
whole works forward another 1.25 inches forward.

Quote:
From weighing the fuselage with tail surfaces before and after, I found the
ratio of the tail wheel weight to total weight to be 0.235 before and 0.253

after. I may have to move the battery to the nose and/or put a cushion
behind my lower back to move the cg further forward. When the wings are
remounted I will be able to see how the total cg compares with what it was
with the 447 and Victor 1+.

Jack B. Hart FF004
Winchester, IN


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DAquaNut(at)aol.com
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PostPosted: Mon Jul 13, 2009 2:39 pm    Post subject: Victor 1+ Report Reply with quote

In a message dated 7/12/2009 10:13:32 P.M. Central Daylight Time, jbhart(at)onlyinternet.net writes:
Quote:
Jack,
  Can you tell us what the HP of the MZ 34 is, and the weight ,and what prop you plan to use?
Quote:
  Ed Diebel Hou. TX Do Not Archive

Quote:

No, it means the FireFly empty weight should be some where around 210
pounds.

Jack B. Hart FF004
Winchester, IN

Looking for love this summer? Find it now on AOL Personals.
[quote][b]


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PostPosted: Tue Jul 14, 2009 1:22 pm    Post subject: Victor 1+ Report Reply with quote

From: DAquaNut(at)aol.com
Date: Mon, 13 Jul 2009 18:35:10 EDT

Quote:

Can you tell us what the HP of the MZ 34 is, and the weight, and what prop you plan to use?

Quote:


Ed,

When I purchased my engine back in February of 2004, it was rated at 27 hp.
It weighed 42 pounds after removing the manual start mechanism. The largest
propeller I can swing by running the engine inverted and rotating the belt
reduction unit up 120 degrees is 55 inches. I have an IVO that I cut power
tips on that is a little over 54 inches that I will use.

Today I mounted the propeller and started shimming the engine to take care
of P factor. Tomorrow I will finish shimming and also slide the battery as
far forward on the root tube as I can. Right now the FireFly minus wings cg
is a little 3.2 inches back from where it was with the Victor 1+ on board.
Today I removed the turtle shell from behind the fuselage to give a little
better air flow over the head and cylinder. Also I measured the weight
difference in propeller blades. These two changes took off another pound.
This brings the fuselage weight down to 45 pounds below what it originally
was. Tomorrow I will check fuselage cg again to see if I am making headway.

Jack B. Hart FF004
Winchester, IN


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John Hauck



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

PostPosted: Tue Jul 14, 2009 2:12 pm    Post subject: Victor 1+ Report Reply with quote

> Today I mounted the propeller and started shimming the engine to take
care
Quote:
of P factor.

Jack B. Hart FF004
Winchester, IN


Never had a P factor problem with a Kolb aircraft of any model, turning up
to 72" 3 blade props with 95 hp (actual), or as little as 35 hp turning a
50" blade.

Wonder why your little FF has a significant enough P factor problem to
warrant off setting thrust line/shimming the engine?

john h
mkIII


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MKIII/912ULS
hauck's holler
Titus, Alabama
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jbhart(at)onlyinternet.ne
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PostPosted: Tue Jul 14, 2009 4:53 pm    Post subject: Victor 1+ Report Reply with quote

At 04:57 PM 7/14/09 -0500, you wrote:
Quote:

Wonder why your little FF has a significant enough P factor problem to
warrant off setting thrust line/shimming the engine?


John,

It is all in how you want to trim out your aircraft for cruise. If I didn't
have a slip ball indicator, I wouldn't worry about it. But if the ball is
out at cruise, you are slipping and that means you are flying with a higher
drag profile than is necessary. If the propeller rotary axis is not
parallel to the direction of travel, there will be P factor. By shimming
one can move the ball closer to the center. When further change gives no
gain, then one can offset the propeller on a pusher aircraft to make up the
difference and bring the ball into center without a trim tab on the rudder.

This problem is common to all single propeller tractor and pusher single
engine aircraft from RC models and on up through large ga and military
aircraft.

More info can be found at:

http://jackbhart.com/firefly/firefly56.html

In terms of significance, it is only how much you want to put into something
to make, in my case, the FireFly a little more economical to fly with
reduced pilot effort. If you use a rudder trim tab to bring in the ball at
cruise without checking for P factor, you run the chance of flying at
reduced propeller efficiencies. The shimming and offset solution is a win
win, in that, the propeller is operating at it's highest efficiency, and
there is no drag caused by an extra trim tab.

Jack B. Hart FF004
Winchester, IN


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John Hauck



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

PostPosted: Tue Jul 14, 2009 7:05 pm    Post subject: Victor 1+ Report Reply with quote

But if the ball is
Quote:
out at cruise, you are slipping and that means you are flying with a
higher
drag profile than is necessary. If the propeller rotary axis is not
parallel to the direction of travel, there will be P factor. By shimming
one can move the ball closer to the center. When further change gives no
gain, then one can offset the propeller on a pusher aircraft to make up
the
difference and bring the ball into center without a trim tab on the
rudder.

>

Quote:
Jack B. Hart FF004
Winchester, IN

How do you trim the aircraft relative wind? I trim mine with the rudder.

How do you counteract adverse yaw caused by the cork screwing prop wash
hitting one side of the vertical stabilizer and relative wind hitting the
opposite side of the rudder? On the MKIII, I do it with a very large trim
tab.

I think p factor has little of no effect on our Kolbs.

During my experiments with the FS and MKIII, I was not able to see any
significant change/advantage in offsetting the engine thrust line
horizontally or vertically.

I know you are an avid experimenter and enjoy attempting to squeeze every
gram of efficiency out of your FF. You also fly much slower and with much
less hp than most of us. However, for the average Kolb flyer like me and
most others, there doesn't seem to be much advantage in changing the
standard engine mount orientation.

john h
mkIII


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hauck's holler
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Thom Riddle



Joined: 10 Jan 2006
Posts: 1597
Location: Buffalo, NY, USA (9G0)

PostPosted: Wed Jul 15, 2009 3:33 am    Post subject: Re: Victor 1+ Report Reply with quote

Jack,

Please keep you reports coming on the MZ installation. I'm sure most would like to see photos when you get a chance too.


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jbhart(at)onlyinternet.ne
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PostPosted: Wed Jul 15, 2009 4:20 am    Post subject: Victor 1+ Report Reply with quote

At 10:05 PM 7/14/09 -0500, you wrote:
Quote:


John,

If your aircraft is trimmed out for your desired cruise, further trimming
with the rudder should be unnecessary, and the ball centering will be
independent of the relative wind.

I do not subscribe to the cork screw prop wash theory. I do subscribe to
the adverse roll caused by the torque reaction between the propeller and the
aircraft. This is countered with a little ailerons bias which then causes
the adverse yaw. This can be removed by P factor adjustment and offsetting
the propeller. Very large trim tabs can be a sign of poor airframe and
engine adjustment.

P factor affects any single propeller aircraft where the propeller rotary
axis is not parallel to the relative wind.

An advantage of the reduction units is to be able to displace the thrust
line to the side without a major weight shift. Also, I have found that the
more propeller wash I can get over the FireFly's low horizontal tail
surfaces the better it performs at low speed and on the ground.

Yes, I do have an advantage in that the FireFly is lighter and slower, but
even so if the FireFly was not well trimmed I would be throwing money away.
Also, it requires more pilot energy to fly an untrimmed aircraft. The
heavier the aircraft and the faster you cruise with the ball off center, the
more it is hitting you in the wallet. Using a trim tab to bring the ball in
is better than cruising with the ball out of center.

Jack B. Hart FF004
Winchester, IN
Quote:

How do you trim the aircraft relative wind? I trim mine with the rudder.

How do you counteract adverse yaw caused by the cork screwing prop wash
hitting one side of the vertical stabilizer and relative wind hitting the
opposite side of the rudder? On the MKIII, I do it with a very large trim
tab.

I think p factor has little of no effect on our Kolbs.

During my experiments with the FS and MKIII, I was not able to see any
significant change/advantage in offsetting the engine thrust line
horizontally or vertically.

I know you are an avid experimenter and enjoy attempting to squeeze every
gram of efficiency out of your FF. You also fly much slower and with much
less hp than most of us. However, for the average Kolb flyer like me and
most others, there doesn't seem to be much advantage in changing the
standard engine mount orientation.

john h
mkIII


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lucien



Joined: 03 Jun 2007
Posts: 721
Location: santa fe, NM

PostPosted: Wed Jul 15, 2009 5:56 am    Post subject: Re: Victor 1+ Report Reply with quote

jbhart(at)onlyinternet.ne wrote:

I do not subscribe to the cork screw prop wash theory. I do subscribe to
the adverse roll caused by the torque reaction between the propeller and the
aircraft. This is countered with a little ailerons bias which then causes
the adverse yaw. This can be removed by P factor adjustment and offsetting
the propeller. Very large trim tabs can be a sign of poor airframe and
engine adjustment.


Don't mean to jump in but, speaking of that... I never could figure out what was going on with my FSII.

One thing I noted with it was it needed left rudder on the takeoff roll to varying degrees depending on what technique I used, i.e. a right-turning tendency. But the prop rotated right hand (and it was a monster too, a 68" WD 3-blade) so the torque or P-factor affects should have caused the plane to go to the _left_. This was how other planes with a RH turning prop I've flown behaved, but my FSII was the opposite.

The only explanation that seemed to fit was the corkscrewing airflow theory, where, I guess, it was hitting the vertical stab from the right and thus trying to swing the plane to the right.

This seemed to be how it behaved in the air too when doing slow flight or slow high powered climbs.

So judging by that, it couldn't have been P-factor or torque but something else stronger than either of those affects. Well, my guess anyway. There was no offset in the engine mounting, the crank was parallel to the tailboom.....

Still scratching my head over that one...

LS


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Titan II SS
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PostPosted: Wed Jul 15, 2009 6:22 am    Post subject: Victor 1+ Report Reply with quote

An interesting experiment:

Chock your main wheels securely and the support the tail of the
airplane by a padded support under the fuselage tube so the tailwheel
is off the ground. Start the engine and add some throttle. As you
blip the throttle watch what the rudder does.

Dennis
Quoting lucien <lstavenhagen(at)hotmail.com>:

Quote:

jbhart(at)onlyinternet.ne wrote:
>
> I do not subscribe to the cork screw prop wash theory. I do subscribe to
> the adverse roll caused by the torque reaction between the propeller and the
> aircraft. This is countered with a little ailerons bias which then causes
> the adverse yaw. This can be removed by P factor adjustment and offsetting
> the propeller. Very large trim tabs can be a sign of poor airframe and
> engine adjustment.
>
Don't mean to jump in but, speaking of that... I never could figure
out what was going on with my FSII.

One thing I noted with it was it needed left rudder on the takeoff
roll to varying degrees depending on what technique I used, i.e. a
right-turning tendency. But the prop rotated right hand (and it was
a monster too, a 68" WD 3-blade) so the torque or P-factor affects
should have caused the plane to go to the _left_. This was how other
planes with a RH turning prop I've flown behaved, but my FSII was
the opposite.

The only explanation that seemed to fit was the corkscrewing airflow
theory, where, I guess, it was hitting the vertical stab from the
right and thus trying to swing the plane to the right.

This seemed to be how it behaved in the air too when doing slow
flight or slow high powered climbs.

So judging by that, it couldn't have been P-factor or torque but
something else stronger than either of those affects. Well, my guess
anyway. There was no offset in the engine mounting, the crank was
parallel to the tailboom.....

Still scratching my head over that one...

LS

--------
LS
Titan II SS


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http://forums.matronics.com/viewtopic.php?p 53123#253123



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PostPosted: Wed Jul 15, 2009 7:40 am    Post subject: Victor 1+ Report Reply with quote

There is an easy way to settle the cork screw debate.

Someone needs to hook a string in the prop wash and see if it blows straight back or if it blows back at an angle supporting the cork screw motion. This can be done on the ground with a string tied to the tail and see what it does. Or maybe even by observing if the rudder is forced to one side or the other while holding the brakes.
As for P-factor that is directly related to how aligned your motor thrust line with the relative wind. You could have a counter or clockwise. It all depends which blade is taking the bigger bite out of the air, that's the one that will have the most torque to exert on the flight path. The Kolb thrust line is pretty close to its center of mass so its moment arm for affecting deviation from flight path is pretty weak, as compared to a Cessna 150. But of course the Kolb is also very light so it may be noticeable even with the short moment arm.

Ron (at) KFHU
================================================
---- lucien <lstavenhagen(at)hotmail.com> wrote:

=============

jbhart(at)onlyinternet.ne wrote:
Quote:

I do not subscribe to the cork screw prop wash theory. I do subscribe to
the adverse roll caused by the torque reaction between the propeller and the
aircraft. This is countered with a little ailerons bias which then causes
the adverse yaw. This can be removed by P factor adjustment and offsetting
the propeller. Very large trim tabs can be a sign of poor airframe and
engine adjustment.



Don't mean to jump in but, speaking of that... I never could figure out what was going on with my FSII.

One thing I noted with it was it needed left rudder on the takeoff roll to varying degrees depending on what technique I used, i.e. a right-turning tendency. But the prop rotated right hand (and it was a monster too, a 68" WD 3-blade) so the torque or P-factor affects should have caused the plane to go to the _left_. This was how other planes with a RH turning prop I've flown behaved, but my FSII was the opposite.

The only explanation that seemed to fit was the corkscrewing airflow theory, where, I guess, it was hitting the vertical stab from the right and thus trying to swing the plane to the right.

This seemed to be how it behaved in the air too when doing slow flight or slow high powered climbs.

So judging by that, it couldn't have been P-factor or torque but something else stronger than either of those affects. Well, my guess anyway. There was no offset in the engine mounting, the crank was parallel to the tailboom.....

Still scratching my head over that one...

LS

--------
LS
Titan II SS


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John Hauck



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

PostPosted: Wed Jul 15, 2009 8:25 am    Post subject: Victor 1+ Report Reply with quote

Jack H/Folks:

Quote:
If your aircraft is trimmed out for your desired cruise, further trimming
with the rudder should be unnecessary, and the ball centering will be
independent of the relative wind.

Relative wind has affected every aircraft I ever flew, fixed and rotary
wing. The fix was step on the ball and get it centered.

Quote:
I do not subscribe to the cork screw prop wash theory.

Cork screw prop wash, on my mkIII, is not theory.

Quote:
Very large trim tabs can be a sign of poor airframe and
engine adjustment.

Might be, but I go with what I have. I have experiemented with different
engine positions/angles, and the old cork screw prop wash never changes. It
keeps hitting the left side of the vertical stab, and relative wind is
hitting the right side of that big rudder. The fix, a rudder trim tab that
will get the job done. Mine keeps the ball of the slip/skid indicator
centered.

Quote:
P factor affects any single propeller aircraft where the propeller rotary
axis is not parallel to the relative wind.

I agree with the above, but not enough to try and correct at normal cruise.
I think my cruise speed is what the aircraft was designed for. If I slow it
down in comparison to the way you fly, everything changes, including the
prop angle of attack in relative wind.

>Also, I have found that the
Quote:
more propeller wash I can get over the FireFly's low horizontal tail
surfaces the better it performs at low speed and on the ground.

Never seen or flown a Kolb aircraft that did not have more than enough prop
wash over the tail to take care of any situation. If there is not enough
prop wash over your FF's tail, it is because you have screwed it up
adjusting prop thrust lines and flying with under powered engines. There
are occassions when a burst of full throttle is all that saved my mkIII from
ground looping, as experienced during my flight from Gallup, NM, to MV,
while landing at Chinle, AZ.

> The heavier the aircraft and the faster you cruise with the ball off
center, the
Quote:
more it is hitting you in the wallet. Using a trim tab to bring the ball
in
is better than cruising with the ball out of center.

Jack B. Hart FF004
Winchester, IN

In a previous post I said you fly a lot different than most of us. Pilot
flying style, model Kolb, interests, engine power, affect aircraft
performance tremendously.

I am happy with my mkIII after nearly 3,000 hours and 17 years living with
and flying it. You would not be happy with my mkIII and I would not be
happy with your FF, the way you have it set up. That is what makes the Kolb
List what it is. If I don't happen to agree with someone, doesn't mean I
don't like them or what they are doing. Just not the way I do it.

I don't tell folks how to do it. I try to share what I do and let you all
pick and choose what they want, if anything.

Getting ready to get out of here in the morning. Got a long boring 800
miles to fly in some really hot, humid, hazy weather. It gets worse as I
get further NE, closer to the larger population centers. I also have to
contend with the Washington DC restricted area. Going to make me fly
further north and west than I would normally. Thanks to the terrorists!!!

jhn h
mkIII


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_________________
John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama
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