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Cross wind capability of the Mk IIIC
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rickofudall

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

Posted: Mon Sep 21, 2009 7:49 am Post subject: Cross wind capability of the Mk IIIC

Took Zulu Delta out Saturday afternoon to see how she handles 90 degree crosswinds. Wind was 8 to 15 (guessing based on report from airport 15 miles away and wind sock activity) Found that it was better to carry a little power, about 3000 rpm (750 at the prop), for rudder effectiveness. When I pulled back to idle on a high approach and put her in a slip it took full rudder deflection to keep her headed down the runway straight. Less rudder seemed to be required when I carried a little power. Looking at the plane afterward and trying to reason it out, I speculated that when the prop is at idle and the stick is forward to slip nose low the rudder is blanked out pretty well. Sound reasonable?

Rick Girard



  [quote][b]

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Thom Riddle

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

Posted: Mon Sep 21, 2009 8:55 am Post subject: Re: Cross wind capability of the Mk IIIC

I'm having a hard time visualizing the rudder on a pusher getting blanked out by any sort of slip.

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Thom Riddle
Buffalo, NY (9G0)

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rickofudall

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

Posted: Tue Sep 22, 2009 3:39 am Post subject: Cross wind capability of the Mk IIIC

Thom, My thinking was that when the engine is cut to idle on approach the prop rpm is increased by the apparent wind making, in effect, a 66" diameter drag chute right in front of the rudder. Combine that with down elevator flying sideways and very little of the vertical stabilizer and rudder is "visible" to the apparent wind. I admit I may be over thinking the problem.  



Rick

do not archive



On Mon, Sep 21, 2009 at 11:55 AM, Thom Riddle <riddletr(at)gmail.com (riddletr(at)gmail.com)> wrote:

 [quote]--> Kolb-List message posted by: "Thom Riddle" <riddletr(at)gmail.com (riddletr(at)gmail.com)>

  

 I'm having a hard time visualizing the rudder on a pusher getting blanked out by any sort of slip.

 

 --------

 Thom Riddle

 Buffalo, NY

 Kolb Slingshot SS-021

 Jabiru 2200A #1574

 Tennessee Prop 64x34

 

 A complex system that works is invariably found to have evolved from a simple system that works.

   - John Gaule

 

 

 

 

 Read this topic online here:

 

 http://forums.matronics.com/viewtopic.php?p=264151#264151

 

 

 

 

 

 

 

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Thom Riddle

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

Posted: Tue Sep 22, 2009 4:22 am Post subject: Re: Cross wind capability of the Mk IIIC

Rick,



Lots of folks think that a prop driven by an engine at idle power produces more drag than thrust but I don't believe that is the case in most airplanes. Following is my rationale for that thinking.



For a propeller that has a fixed pitch in flight, there is an rpm for every true airspeed that creates zero thrust and zero drag. In my airplane that I documented most thoroughly, my typical approach speed was 65 mph IAS which during typical ambient conditions equated to 61 mph TAS. For my engine and prop setup the zero thrust rpm for that airspeed was 2288 rpm. Any rpm greater than this zero thrust rpm at that airspeed would result in positive net thrust. IF at that airspeed you could get the engine rpm below that engine speed, then the result would be net drag from the prop. In my experience, the way most engine/props are typically set up, it is difficult or even impossible to get the engine rpm below the zero thrust speed at idle during normal glide approach. Your airplane may not be this way but all of mine have exhibited this characteristic. In the case of the airplane I'm referring to, my approach speed of 61 TAS and idle power resulted in about 2700 rpm or thereabouts. This means that the prop was producing a net positive thrust at idle power on approach. To confirm my theory, I have done engine off approaches (prop stopped) at my normal approach speed with the net result being a much steeper glide than with the engine at idle speed, i.e., the descent rate at the same airspeed was much greater than at idle power. Your airplane may be different but every one I've owned and tested behaved this way. 



If you know the pitch setting in inches for your prop, prop speed reduction ratio, and the TAS of your idle power approach, you can calculate the zero thrust rpm. If your engine is turning higher than this zero thrust speed under those conditions, your prop is producing a net positive thrust. If it is turning less than that zero thrust rpm, then your prop is producing a net drag force. The further away from this zero thrust rpm your engine is turning, the greater the magnitude of the net thrust or net drag.



If you need help calculating this for your airplane let me know and I'll be glad to help you figure it out.

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Thom Riddle
Buffalo, NY (9G0)

Don't worry about old age... it doesn't last very long.
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rickofudall

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

Posted: Tue Sep 22, 2009 5:52 am Post subject: Cross wind capability of the Mk IIIC

Thom, On the other hand, my 582 idles at 1800 rpm (450 prop rpm) when all warmed up. Depending on speed the lowest rpm I see on approach is 2200 (550) to 2400 (600). That extra energy has to come from someplace and the only answer is the apparent wind flowing by the prop. I can tell the difference in sink speed if I open the throttle enough to relieve that loading without increasing rpm. When I had that gawd awful Rice King clutch in the gear box I could really see the difference as then the prop had no engine assistance and glide was of space shuttle variety. Again, power was extracted from the apparent wind. The question is, does that drag block or inhibit airflow and shadow the rudder? I'm inclined to think it does.

Be comparison with the Mk III, I've landed a 150 in direct crosswinds of 30 mph and still had rudder available to maintain heading on the runway centerline. In 1/3 that wind (on average judging by the windsock) the Mk III rudder was mostly against the stop if I cut to idle power.

 



Rick Girard

do not archive



On Tue, Sep 22, 2009 at 7:23 AM, Thom Riddle <riddletr(at)gmail.com (riddletr(at)gmail.com)> wrote:

 [quote]--> Kolb-List message posted by: "Thom Riddle" <riddletr(at)gmail.com (riddletr(at)gmail.com)>

  

 Rick,

 

 Lots of folks think that a prop driven by an engine at idle power produces more drag than thrust but I don't believe that is the case in most airplanes. Following is my rationale for that thinking.

 

 For a propeller that has a fixed pitch in flight, there is an rpm for every true airspeed that creates zero thrust and zero drag. In my airplane that I documented most thoroughly, my typical approach speed was 65 mph IAS which during typical ambient conditions equated to 61 mph TAS. For my engine and prop setup the zero thrust rpm for that airspeed was 2288 rpm. Any rpm greater than this zero thrust rpm at that airspeed would result in positive net thrust. IF at that airspeed you could get the engine rpm below that engine speed, then the result would be net drag from the prop. In my experience, the way most engine/props are typically set up, it is difficult or even impossible to get the engine rpm below the zero thrust speed at idle during normal glide approach. Your airplane may not be this way but all of mine have exhibited this characteristic. In the case of the airplane I'm referring to, my approach speed of 61 TAS and idle power resulted in about 2700 rpm or thereabouts!

   . This means that the prop was producing a net positive thrust at idle power on approach. To confirm my theory, I have done engine off approaches (prop stopped) at my normal approach speed with the net result being a much steeper glide than with the engine at idle speed, i.e., the descent rate at the same airspeed was much greater than at idle power. Your airplane may be different but every one I've owned and tested behaved this way.

  

 If you know the pitch setting in inches for your prop, prop speed reduction ratio, and the TAS of your idle power approach, you can calculate the zero thrust rpm. If your engine is turning higher than this zero thrust speed under those conditions, your prop is producing a net positive thrust. If it is turning less than that zero thrust rpm, then your prop is producing a net drag force. The further away from this zero thrust rpm your engine is turning, the greater the magnitude of the net thrust or net drag.

  

 If you need help calculating this for your airplane let me know and I'll be glad to help you figure it out.

 

 --------

 Thom Riddle

 Buffalo, NY

 Kolb Slingshot SS-021

 Jabiru 2200A #1574

 Tennessee Prop 64x34

 

 A complex system that works is invariably found to have evolved from a simple system that works.

   - John Gaule

 

 

 

 

 Read this topic online here:

 

 http://forums.matronics.com/viewtopic.php?p=264288#264288

 

 

 

 

 

 

 

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 ="_blank">http://www.matronics.com/contribution

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Thom Riddle

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

Posted: Tue Sep 22, 2009 6:10 am Post subject: Re: Cross wind capability of the Mk IIIC

Rick,



Perhaps but...



If the prop is turning at a rate that gives it a positive angle of attack with the relative wind, a necessity by definition if more than the zero thrust speed, then the prop is not being "pushed" by the prevailing wind, rather it is producing thrust. The reason that the idle speed in glide is higher than the static idle speed is that the angle of attack is much less when moving forward than it is when stationary, but it is still a positive angle of attack if the rpm is greater than the zero thrust rpm for a given airspeed. 



That is my intuitive understanding of the situation. It could be wrong but I don't understand how if it is.



Any aerodynamicists among us who would like to clear this up?

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Thom Riddle
Buffalo, NY (9G0)

Don't worry about old age... it doesn't last very long.
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John Hauck

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

Posted: Tue Sep 22, 2009 6:50 am Post subject: Cross wind capability of the Mk IIIC

Must have been a humongous rudder on that  150.

  

 I am not 150 qualifed, but I bet the book says the  max cross wind component is about 15 mph at 90 degrees.

  

 john h

 mkIII

 Rock House, Oregon

  

  

  

 [quote]    Be comparison with the Mk III, I've landed    a 150 in direct crosswinds of 30 mph and still had rudder available to    maintain heading on the runway centerline. In 1/3 that wind (on average    judging by the windsock) the Mk III rudder was mostly against the stop if I    cut to idle power.

      



   Rick Girard

    



[b]

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

John Hauck

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

Posted: Tue Sep 22, 2009 7:06 am Post subject: Cross wind capability of the Mk IIIC

 	  Quote: 	
		   Any aerodynamicists among us who would like to clear this up?



 --------

 Thom Riddle


	


I discovered the difference between engine idle power glide and dead stick 

glide by experimenting.



Dead stick significantly increases glide in a Kolb.  Don't know about other 

airplanes because I never experiemented with them.



I have always felt folks needed to learn how to fly their Kolbs at idle 

power, and also practice dead stick landings.  The reason, the glide is so 

much better dead stick, one could get into trouble selecting a forced 

landing area and over flying it.



Can't prove it on paper, nor do I have any desire to, but the prop disc 

becomes a large round disc when reduced to engine idle power.  An example of 

this is a helicopter in autorotation.  If the main rotor blades did not slow 

the aircraft down by increasing drag, it would fall out of the sky.  A 

gyrocopter is continuously autorotating because it is a big pin wheel. 

Probably why it takes so much power to fly.



My own opinion.  Worth what you paid for it.



Take care,



john h

mkIII

Rock House, Oregon

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

JetPilot

Joined: 10 Jan 2006
Posts: 1246

Posted: Tue Sep 22, 2009 8:39 am Post subject: Re: Cross wind capability of the Mk IIIC

In almost all airplanes, stopping the prop completely reduces drag and increases glide.   A windmilling prop is much worse than a stopped one if you are trying to glide.   As John H says, a helicopter would fall out of the air if this were not true.  A gyrocopter just has a big windmilling prop on the top of it, no power to it at all, and if it were to ever stop windmilling in the air the gyrocopter would fall like a rock.



John H,



Have you ever tried Dead stick gliding and landings in your MK III ???   My minimum descent rate in my Kolb MK III Xtra is 500 FPM at 55 MPH and 1800 RPM - Minimum Idle power for my Rotax 912-S.   When I shut down the engine and stop the prop completely, my descent rate increases to 900 Feet per minute, it is much worse      This was the total opposite of what I was expecting, but I have done this a number of times and this is just the way it is in my Kolb.   It does not make any sense and goes against theory, but I have tried varying the airspeeds, and tested this quite a number of times with always the same result, when I stop the prop instead of idle at 1800 RPM, my glide is reduced by a huge amount.   



Mike

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Kolb MK-III Xtra, 912-S

Thom Riddle

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

Posted: Tue Sep 22, 2009 8:43 am Post subject: Re: Cross wind capability of the Mk IIIC

For more on zero thrust rpm see the following:



http://cafefoundation.org/v2/aboutcafe_orderfromchaos.php

_________________
Thom Riddle
Buffalo, NY (9G0)

Don't worry about old age... it doesn't last very long.
- Anonymous

JetPilot

Joined: 10 Jan 2006
Posts: 1246

Posted: Tue Sep 22, 2009 8:52 am Post subject: Re: Cross wind capability of the Mk IIIC

My best guess for the situation above is that my Rotax 912-S must be producing a significant amount of thrust even at 1800 RPM idle power...   Rotax prohibits idling this engine below 1800 RPM, so I don't have any figures below that RPM where the prop probably goes from still producing some thrust to windmilling and creating drag instead of thrust.  Just a guess, that this is the only thing that makes sense.   



1800 RPM =  Minimum Descent rate at 55 MPH 500 Feet Per Minute

Prop Stopped = Minimum Descent rate at 55 MPH 900 Feet Per Minute



The did this test many times and at different airspeeds, the test results don't lie..  Something has to be causing it.   Those thinking that they may have the same glide with the engine stopped that they have at idle power should really try this one day, they might be in for a big surprise, I sure was !!!    PS, start High up and make sure you have a HUGE runway, and aim for the middle, because you might end up much shorter than you expect.   Some Kolbs actually glide better with the prop stopped, the reports are out there, which is why I suggest trying it under very controlled conditions, because it is better to know what to expect rather than be surprised if your engine ever does completely quit.



Mike

_________________
"NO FEAR" - If you have no fear you did not go as fast as you could have !!!

Kolb MK-III Xtra, 912-S

Possums

Joined: 03 Nov 2007
Posts: 247

Posted: Tue Sep 22, 2009 9:41 am Post subject: Cross wind capability of the Mk IIIC

At 12:52 PM 9/22/2009, you wrote:

 	  Quote: 	
		  



My best guess for the situation above is that my Rotax 912-S must be 

producing a significant amount of thrust even at 1800 RPM idle 

power...   Rotax prohibits idling this engine below 1800 RPM, so I 

don't have any figures below that RPM where the prop probably goes 

from still producing some thrust to windmilling and creating drag 

instead of thrust.  Just a guess, that this is the only thing that 

makes sense.



1800 RPM =  Minimum Descent rate at 55 MPH 500 Feet Per Minute

Prop Stopped = Minimum Descent rate at 55 MPH 900 Feet Per Minute


	


Does the prop windmill on a 912 engine? It won't on a 503 with no clutch.

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Possum

JetPilot

Joined: 10 Jan 2006
Posts: 1246

Posted: Tue Sep 22, 2009 9:59 am Post subject: Re: Cross wind capability of the Mk IIIC

 	  Possums wrote: 	
		  

Does the prop windmill on a 912 engine? It won't on a 503 with no clutch. 	
 



No, the prop comes to a very abrupt and sudden stop when the engine is shut down on a 912-S.  I think even if I dived to over 100 MPH and the prop would still not windmill.



I remember some engine off videos you posted a long time back Possums, did your glide increase or decrease with the engine off ?



Mike

_________________
"NO FEAR" - If you have no fear you did not go as fast as you could have !!!

Kolb MK-III Xtra, 912-S

rickofudall

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

Posted: Tue Sep 22, 2009 10:38 am Post subject: Cross wind capability of the Mk IIIC

Thom, If your conjecture was true windmills would be increasing the rate of the earth's rotation. 



Rick Girard

do not archive



On Tue, Sep 22, 2009 at 1:29 PM, Richard Girard <aslsa.rng(at)gmail.com (aslsa.rng(at)gmail.com)> wrote:

 [quote]John, The book says demonstrated cross wind capability, not maximum. I had a girl friend who lived at the beach. I suppose I could call it a humongous rudder but I'm more modest than that.  



Rick



 

On Tue, Sep 22, 2009 at 9:50 AM, John Hauck <jhauck(at)elmore.rr.com (jhauck(at)elmore.rr.com)> wrote:

 	  Quote: 	
		           Must have been a humongous rudder on that  150.

  

 I am not 150 qualifed, but I bet the book says the  max cross wind component is about 15 mph at 90 degrees.

  

 john h

 mkIII

 Rock House, Oregon

  

  

  

  	  Quote: 	
		      Be comparison with the Mk III, I've landed    a 150 in direct crosswinds of 30 mph and still had rudder available to    maintain heading on the runway centerline. In 1/3 that wind (on average    judging by the windsock) the Mk III rudder was mostly against the stop if I    cut to idle power.

      



   Rick Girard

    



	
    	  Quote: 	
		  



get="_blank">http://www.matronics.com/Navigator?Kolb-List

tp://forums.matronics.com

_blank">http://www.matronics.com/contribution



	




	




 [b]

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rickofudall

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

Posted: Tue Sep 22, 2009 10:39 am Post subject: Cross wind capability of the Mk IIIC

John, The book says demonstrated cross wind capability, not maximum. I had a girl friend who lived at the beach. I suppose I could call it a humongous rudder but I'm more modest than that. 



Rick

 

On Tue, Sep 22, 2009 at 9:50 AM, John Hauck <jhauck(at)elmore.rr.com (jhauck(at)elmore.rr.com)> wrote:

[quote]        Must have been a humongous rudder on that  150.

  

 I am not 150 qualifed, but I bet the book says the  max cross wind component is about 15 mph at 90 degrees.

  

 john h

 mkIII

 Rock House, Oregon

  

  

  

  	  Quote: 	
		      Be comparison with the Mk III, I've landed    a 150 in direct crosswinds of 30 mph and still had rudder available to    maintain heading on the runway centerline. In 1/3 that wind (on average    judging by the windsock) the Mk III rudder was mostly against the stop if I    cut to idle power.

      



   Rick Girard

    



	
    	  Quote: 	
		  



get="_blank">http://www.matronics.com/Navigator?Kolb-List

tp://forums.matronics.com

_blank">http://www.matronics.com/contribution



	




[b]

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The smallest miracle right in front of you is enough to make you happy....

rickofudall

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

Posted: Tue Sep 22, 2009 10:46 am Post subject: Cross wind capability of the Mk IIIC

They don't go into the detail of how zero thrust is found in this article, although they did in another. Sorry, I don't have the reference, but the method was relatively simple. Measure the crankshaft's end play with a force gauge. When the prop is being pushed backward it's producing drag, when it's pulled forward it's producing thrust. In the middle it's in zero thrust mode. 



Rick Girard

do not archive



On Tue, Sep 22, 2009 at 11:43 AM, Thom Riddle <riddletr(at)gmail.com (riddletr(at)gmail.com)> wrote:

 [quote]--> Kolb-List message posted by: "Thom Riddle" <riddletr(at)gmail.com (riddletr(at)gmail.com)>

  

 For more on zero thrust rpm see the following:

 

 http://cafefoundation.org/v2/aboutcafe_orderfromchaos.php

 

 --------

 Thom Riddle

 Buffalo, NY

 Kolb Slingshot SS-021

 Jabiru 2200A #1574

 Tennessee Prop 64x34

 

 A complex system that works is invariably found to have evolved from a simple system that works.

   - John Gaule

 

 

 

 

 Read this topic online here:

 

 http://forums.matronics.com/viewtopic.php?p=264336#264336

 

 

 

 

 

 

 

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 arget="_blank">http://www.matronics.com/Navigator?Kolb-List

 ===========

 http://forums.matronics.com

 ===========

 le, List Admin.

 ="_blank">http://www.matronics.com/contribution

 ===========

 

 

 

 [b]

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Possums

Joined: 03 Nov 2007
Posts: 247

Posted: Tue Sep 22, 2009 10:57 am Post subject: Cross wind capability of the Mk IIIC

At 01:59 PM 9/22/2009, you wrote:

 	  Quote: 	

Possums wrote:

 >

 > Does the prop windmill on a 912 engine? It won't on a 503 with no clutch.

No, the prop comes to a very abrupt and sudden stop when the engine 

is shut down on a 912-S.  I think even if I dived to over 100 MPH 

and the prop would still not windmill.

I remember some engine off videos you posted a long time back 

Possums, did your glide increase or decrease with the engine off ?

Mike

--------

&quot;NO FEAR&quot; -  If you have no fear you did not go as fast as 

you could have !!!

Mine glides better with the prop stopped. About 500 fpm? drop on a 

nice calm day.

_________________
Possum

Thom Riddle

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

Posted: Tue Sep 22, 2009 11:11 am Post subject: Re: Cross wind capability of the Mk IIIC

[size=12]Rick,



To help clear up my understanding of your working theory please answer the following questions:



1- When flying at cruise power or higher, is your prop producing a net positive thrust force or net drag force (negative thrust)?



2- Would the glide performance of your airplane with power off and prop stopped be better or worse than if the prop were not even on the engine? In other words, would the total drag of the airplane gliding at a given speed be more or less with a stopped prop or no prop at all on the airplane?



Thanks for your help.

_________________
Thom Riddle
Buffalo, NY (9G0)

Don't worry about old age... it doesn't last very long.
- Anonymous

zeprep251(at)aol.com
Guest

Posted: Tue Sep 22, 2009 1:25 pm Post subject: Cross wind capability of the Mk IIIC

Hey guys,

  My 503 idled at 1780 rpm,but it would always be turning 2200 or better on landing with the nose down and it really helped keep the speed down,you could feel it.3 blade IVO.

  G.Aman

 

   

 

   

 

 --

rickofudall

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

Posted: Tue Sep 22, 2009 1:25 pm Post subject: Cross wind capability of the Mk IIIC

1. Thrust, just like all the books say. No thrust, no level flight. The prop produces net thrust, the airframe produces net drag. In unaccelerated flight, they balance. But those are conditions beyond your question, you didn't specify level flight so the answer to it is, it depends. 

 I cruise at 5200 rpm. In level flight that gets me about 65 mph IAS. I change nothing but the stick position by pushing it forward and speed goes up slightly at first, but so does rpm as the prop unloads the engine. I keep pushing forward but now the prop is loading the engine in reverse which is preventing the prop from turning any faster and it is now producing drag. Speed will rise IF the airplanes kinetic energy overcomes that greater net drag of airframe and wind driven prop. When it doesn't acceleration stops and things are again in balance. 2. My airplane has a 582 and a 4:00 to 1 gearbox. The only way the prop can be stopped in flight is if the engine seized.  However, if the prop were stopped it would be about the same as a 66" long piece of 2 X 4 stuck flat side against the wind and produce about the same amount of drag. More drag, same lift, worse lift to drag ratio. Take away the stopped prop, less drag, same lift, better lift to drag ratio.

 



Rick Girard

do not archive



On Tue, Sep 22, 2009 at 2:11 PM, Thom Riddle <riddletr(at)gmail.com (riddletr(at)gmail.com)> wrote:

 [quote]--> Kolb-List message posted by: "Thom Riddle" <riddletr(at)gmail.com (riddletr(at)gmail.com)>

  

 [size=12]Rick,

 

 To help clear up my understanding of your working theory please answer the following questions:

 

 1- When flying at cruise power or higher, is your prop producing a net positive thrust force or net drag force (negative thrust)?

 

 2- Would the glide performance of your airplane with power off and prop stopped be better or worse than if the prop were not even on the engine? In other words, would the total drag of the airplane gliding at a given speed be more or less with a stopped prop or no prop at all on the airplane?

  

 Thanks for your help.

 

 --------

 Thom Riddle

 Buffalo, NY

 Kolb Slingshot SS-021

 Jabiru 2200A #1574

 Tennessee Prop 64x34

 

 A complex system that works is invariably found to have evolved from a simple system that works.

   - John Gaule

 

 

 

 

 Read this topic online here:

 

 http://forums.matronics.com/viewtopic.php?p=264359#264359

 

 

 

 

 

 

 

 ===========

 arget="_blank">http://www.matronics.com/Navigator?Kolb-List

 ===========

 http://forums.matronics.com

 ===========

 le, List Admin.

 ="_blank">http://www.matronics.com/contribution

 ===========

 

 

 

 [b]

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