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Control Surface Flutter ????

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Richard Pike

Joined: 09 Jan 2006
Posts: 1670
Location: Blountville, Tennessee

Posted: Thu Feb 16, 2006 7:27 pm Post subject: Control Surface Flutter ????

<http://www.bcchapel.org/pages/0003/pg6.htm>The MKIII has aileron 

counterbalances because the ailerons are bad to flutter. It is most 

discomfiting to look at your right wingtip and see it become a blur.  I 

had added approx 1.5 ounces to the trailing edge of the right aileron 

for a manually adjustable trim tab. That was 1.5 ounces too much.



It is even worse to have your rudder start to flutter and immediately 

have your wingman sounding very tense in your headset saying "What ever 

you are doing, quit - the boom tube is starting to look like a sine 

wave!" I had added approximately 3 ounces to the rudder trailing edge 

for a nav light and a fixed trim tab. It was way too much.

So now my rudder also has a counterbalance. Remember that web page of 

mine that you couldn't find? The rudder counterbalance is on there.

http://www.bcchapel.org/pages/0003/pg6.htm



If you are planning on adding 8 ounces to your Kolb control surface 

trailing edges, you have your work cut out for you, because they will 

flutter. Gare-on-teed. Plan on it.



Richard Pike

MKIII N420P (420ldPoops)



JetPilot wrote:

 	  Quote: 	
		   



 Has anyone ever had control surface flutter in a Kolb ?  Or the warning signs of flutter such as them starting to buzz at high speeds ?  I am planning on putting electric trim tabs on all the control surfaces which will add a little weight to them on the trailing edge (about 8 ounces each), but im hoping not enough weight to induce flutter.   Any information or experience on flutter on Kolbs would be greatly appreciated.



 Michael A. Bigelow



 --------

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





 Read this topic online here:



 http://forums.matronics.com/viewtopic.php?p=12792#12792

_________________
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0

Forgiving is tough, being forgiven is wonderful, and God's grace really is amazing.

martin_burns(at)ntlworld.
Guest

Posted: Fri Feb 17, 2006 2:18 pm Post subject: Control Surface Flutter ????

We too have experienced aileron flutter on our Mark IIIC, well below Vne.

Can anyone tell me more about the counterbalances available for the ailerons

and how they are fitted?



Martin Burns

Scotland



Do not archive

Richard Pike

Joined: 09 Jan 2006
Posts: 1670
Location: Blountville, Tennessee

Posted: Fri Feb 17, 2006 2:52 pm Post subject: Control Surface Flutter ????

Email New Kolb Co. and ask them, they will be glad to sell you a pair. 

They slide into the aileron main tube and are riveted in place. They 

have a sliding counter weight that you can slide in and out until the 

ailerons are content to lay in neutral. (Disconnect the control rods 

first) Then rivet the slider in place.



Richard Pike

MKIII N420P (420ldPoops)



Martin Burns wrote:

 	  Quote: 	
		   



 We too have experienced aileron flutter on our Mark IIIC, well below Vne.

 Can anyone tell me more about the counterbalances available for the ailerons

 and how they are fitted?



 Martin Burns

 Scotland



 Do not archive

_________________
Richard Pike
Kolb MKIII N420P (420ldPoops)
Kingsport, TN 3TN0

Forgiving is tough, being forgiven is wonderful, and God's grace really is amazing.

Dave Pelletier

Joined: 10 Jan 2006
Posts: 100
Location: Prescott, Arizona

Posted: Fri Feb 17, 2006 3:24 pm Post subject: Control Surface Flutter ????

Be careful if you rivet in place.  I put counter weights on my Firestar then 

(DUH!) they stuck up too high with the wings folded to get in the trailer. 

(I trailered mine all the time.)  So un-riveted and put in a 3/16" (I think) 

bolt so the counterweights could slide in the tube for storage.  Worked 

fine.



AzDave

---

_________________
AzDave

neilsenrmf(at)comcast.net
Guest

Posted: Sat Feb 18, 2006 7:12 am Post subject: Control Surface Flutter ????

I put trailing edge material (from Aircraft Spruce) on the trailing edge of 

my ailerons and flaps for a cleaner more streamline look rather than use the 

recommended method. I got the approval from Kolb to do this but they 

suggested that I put the optional (at that time) balance weights on to avoid 

flutter caused by the minor increased weight (couldn't have been more than 

an ounce if that). I installed the balance weights but only used about two 

inches of the heavy balance weights bolted to the ends of the balance arms. 

While flying with my direct drive VW I never had a problem but when I 

switched to my redrive VW I experienced a low frequency flutter. The redrive 

VW cruised a good ten miles an hour faster using the same horse power. When 

I started nudging 80 MPH the flutter would start. I then changed the balance 

weights too ones that are app. four inches long with only one inch in the 

balance arm. This has fixed the flutter problem and I have seen app. 95 MPH 

for a few minutes and not even the hint of flutter.



I try to keep my empty weight down. I have read that people slide the 

included weight in and out of the balance arm till the ailerons balance. I 

suggest that the ailerons get balanced but they be balanced so that when 

they are balanced there is only a inch or so in the balance arm with the 

unneeded weight cut off rather than slid into the balance arm.



Rick Neilsen

Redrive VW powered MKIIIc



---

jindoguy(at)gmail.com
Guest

Posted: Sat Feb 18, 2006 2:02 pm Post subject: Control Surface Flutter ????

Being such a high time Kolb pilot, 7 take offs, 7 landings and two go

arounds so far, and this is the one thing I really remember about the fifth

circuit around the patch. There was some light to moderate thermal activity

and I sensed a low rumbling and a little feedback from the stick as I

approached 85 MPH while trying to maintain altitude in the pattern. I looked

out the left side, 46 Hotel is flown from the right, and saw waves in the

wing skin and the left aileron flapping up and down. I pulled the throttle

back and watched the amplitude of the aileron excursions decrease and quit.

It was a bit unnerving but I made the landing, looked the aileron over for

any damage, inspected the hinge attachment rivets, and generally calmed

down. There was no damage and I didn't experience any more flutter during

the remaining two circuits, but I did use throttle to control my altitude

from then on and didn't approach the critical airspeed that seemed to bring

on the flutter again. I've done a better examination of the aileron and

hinge line since and have confirmed that there was no defprmation or damage.

I didn't build 46 Hotel, so I can't attest to how heavy or light the left

aileron is compared to the right. I'll put counter balances on the ailerons

before I fly it again.



On 2/16/06, JetPilot <orcabonita(at)hotmail.com> wrote:

 	  Quote: 	
		  

 



 Has anyone ever had control surface flutter in a Kolb ?  Or the warning

 signs of flutter such as them starting to buzz at high speeds ?  I am

 planning on putting electric trim tabs on all the control surfaces which

 will add a little weight to them on the trailing edge (about 8 ounces each),

 but im hoping not enough weight to induce flutter.   Any information or

 experience on flutter on Kolbs would be greatly appreciated.



 Michael A. Bigelow



 --------

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

 !!!





 Read this topic online here:



 http://forums.matronics.com/viewtopic.php?p=3D12792#12792




	




--

Rick Girard

"Pining for a home on the Range"

JetPilot

Joined: 10 Jan 2006
Posts: 1246

Posted: Sat Feb 18, 2006 7:45 pm Post subject: Re: Control Surface Flutter ????

Thanks for the information everyone !!!  



After reading what everyone had to say I did a bunch of research on the net and read about a lot of cases of flutter caused by loose trim tabs, etc. etc.     The more I read the more adding trim tabs scares me....  I will just use the bungee trim system Kolb provides.  I was really looking foward to electric trim, I just dont think its worth the very real risk of a catastrophic fialure caused by flutter.



Richard, I remember your nav light causing your rudder to flutter a bit, but I did not know ailerons were also so prone to flutter.  Hopefully Kolb put ailerons counterweights in my MK-III kit, but if not I will add them.



Michael A. Bigelow

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

Kolb MK-III Xtra, 912-S

rsanoa

Joined: 10 Jan 2006
Posts: 71
Location: Bell Buckle,TN

Posted: Sun Feb 19, 2006 6:17 am Post subject: Control Surface Flutter ????

Been flying since 1935, owned 16 different types of aircraft and never, never heard  or seen a case of control flutter caused by a trim tab, usually weighing maybe a half ounce loosening. I've used dozens and dozens, had some loosen over time and never seen a problem.  I'll concede there may be cases of large motor driven types, with heavy installation on the trailing edge causing problems, never used that type,  but a small thin tab, I don't think so.  I've been proven wrong about a lot of things in 88 years so take it for what it might be worth.

Ray .. down to a non fluttering UltraStar

  Tennessee

  do not archive

JetPilot <orcabonita(at)hotmail.com> wrote:

  

<<After reading what everyone had to say I did a bunch of research on the net and read about a lot of cases of flutter caused by loose trim tabs, etc. etc. [Shocked] The more I read the more adding trim tabs scares me.... >>

Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=13251#13251

		

---------------------------------

_________________
Ray S.Anderson

rsanoa

Joined: 10 Jan 2006
Posts: 71
Location: Bell Buckle,TN

Posted: Sun Feb 19, 2006 8:00 am Post subject: Control Surface Flutter ????

Hey guys, we may be getting into dangerous ground here. I'm sure there are Kolbers on both sides of the fence here with sincere and firm convictions in each view. An example is me. I'm so conservative I though Barry Goldwater was a flaming liberal. I'm surrounded by children and grandchildren who are 'yellow dog democrats'.  We have an understanding that we don't get into political discussions around each other. My ties to the Republican party go back to ole Abe Lincoln. My grandfather, yes my grandfather, voted for Abe back in Baltimore before the 'late unpleasantness'.  My fathers father was a damn Yankee living there and enlisted in the Union Army and fought through the war before becoming a 'carpetbagger' and moving to Noth Carolina, where be met my grandmother who was only 16-17, and she became besotted with him and married him much to the chagrin of her folks. Reason, her father had fought in the correct army and had been killed in the battle of Petersburg, while her ne

 w

 husband (damn yankee) had fought in the same battle for the blue bellies and survived. 

  My father and two brothers were taught sound Republicism at their fathers knee, who passed it on to me. My mother was a 'yellow dog democrat' so you can see I was raised to 'dont discuss politics among family'. When I was a child I heard some interesting conversations when they thought the children were out of earshot !!!  Come to think about it, I may be the only person in the group who can claim "My grandaddy voted for Abe Lincoln".

  So you see, a Kolb doesn't really care who flies it, Republican or Democrat.

  Ray

  Tenn.... Non fluttering UltraStar

  do not archive



ray anderson <rsanoa(at)yahoo.com> wrote: 

  



Been flying since 1935, owned 16 different types of aircraft and never, never heard or seen a case of control flutter caused by a trim tab, usually weighing maybe a half ounce loosening. I've used dozens and dozens, had some loosen over time and never seen a problem. I'll concede there may be cases of large motor driven types, with heavy installation on the trailing edge causing problems, never used that type, but a small thin tab, I don't think so. I've been proven wrong about a lot of things in 88 years so take it for what it might be worth.

Ray .. down to a non fluttering UltraStar

Tennessee

do not archive

JetPilot wrote:


<>

Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=13251#13251



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Brings words and photos together (easily) with

_________________
Ray S.Anderson

flht99reh(at)netzero.net
Guest

Posted: Sun Feb 19, 2006 8:19 am Post subject: Control Surface Flutter ????

Ray and board, you are 100% correct. I thought I was responding to Ed off

site and directly. I'm sorry. I know after following this board history that

this is where the battle begins. I don't want that for the boards sake, the

sake of individuals that rely on the informative side of this site and for

the sake of making enemies. We as a people (not party) have enough people

mad at us. Ed, I'm sorry. Christ said that they will know you by your

actions. My response to you should have been sent only to you and out of

love. Sorry.



And I agree with Ed, this thread has been used up. There was a time when the

site was dead, I had a question, and others had answers. I thank them all

for their input. Especial regarding where you can get the information and

the interesting part about the HDTV towers in the future.



Corrected Ralph of Ohio.





--

Mike Schnabel

Joined: 27 Jan 2006
Posts: 114
Location: Manchester, TN

Posted: Sun Feb 19, 2006 11:14 am Post subject: Control Surface Flutter ????

Ray,

   

  Well spoken eulogy for the thread. May it rest in peace! How interesting it is that you may be, and probably are, the only Kolber with a connection to good old Abe's nomination and eventual presidency. We must find some time to grill a burger or two, i think (Know) i would love to hear some of your other tales!

   

  Thanks for helping keep us all on a level plain, without a sense of reality, its easy to lose focus. Always keep your eye on the ball... 

   

  Mike S

  Manchester TN

   

  do not archive



ray anderson <rsanoa(at)yahoo.com> wrote:

  



Hey guys, we may be getting into dangerous ground here. I'm sure there are Kolbers on both sides of the fence here with sincere and firm convictions in each view. An example is me. I'm so conservative I though Barry Goldwater was a flaming liberal. I'm surrounded by children and grandchildren who are 'yellow dog democrats'. We have an understanding that we don't get into political discussions around each other. My ties to the Republican party go back to ole Abe Lincoln. My grandfather, yes my grandfather, voted for Abe back in Baltimore before the 'late unpleasantness'. My fathers father was a damn Yankee living there and enlisted in the Union Army and fought through the war before becoming a 'carpetbagger' and moving to Noth Carolina, where be met my grandmother who was only 16-17, and she became besotted with him and married him much to the chagrin of her folks. Reason, her father had fought in the correct army and had been killed in the battle of Petersburg, while her ne

w

husband (damn yankee) had fought in the same battle for the blue bellies and survived. 

My father and two brothers were taught sound Republicism at their fathers knee, who passed it on to me. My mother was a 'yellow dog democrat' so you can see I was raised to 'dont discuss politics among family'. When I was a child I heard some interesting conversations when they thought the children were out of earshot !!! Come to think about it, I may be the only person in the group who can claim "My grandaddy voted for Abe Lincoln".

So you see, a Kolb doesn't really care who flies it, Republican or Democrat.

Ray

Tenn.... Non fluttering UltraStar

do not archive



ray anderson wrote: 




Been flying since 1935, owned 16 different types of aircraft and never, never heard or seen a case of control flutter caused by a trim tab, usually weighing maybe a half ounce loosening. I've used dozens and dozens, had some loosen over time and never seen a problem. I'll concede there may be cases of large motor driven types, with heavy installation on the trailing edge causing problems, never used that type, but a small thin tab, I don't think so. I've been proven wrong about a lot of things in 88 years so take it for what it might be worth.

Ray .. down to a non fluttering UltraStar

Tennessee

do not archive

JetPilot wrote:


<>

Read this topic online here:



http://forums.matronics.com/viewtopic.php?p=13251#13251



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JetPilot

Joined: 10 Jan 2006
Posts: 1246

Posted: Mon Feb 20, 2006 3:56 am Post subject: Re: Control Surface Flutter ????

I have been searching the archives, and there seems to be a lot in there about flutter on Kolbs     I have several cases where people have put counterweights on thier ailerons and rudder...



Has anyone ever had  flutter in the elevators or put counterweights on those ?

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

Kolb MK-III Xtra, 912-S

John Hauck

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

Posted: Mon Feb 20, 2006 7:17 am Post subject: Control Surface Flutter ????

| I have been searching the archives, and there seems to be a lot in 

there about flutter on Kolbs  [Shocked]



Mike B:



Should not be shocked if you look at the way those big ailerons are 

hung on the wing by their leading edge.



I experienced aileron flutter on my Ultrastar, Firestar, and MKIII. 

Was not until Old Kolb experienced flutter with the FSII that a fix 

was designed and produced.  Soon as they became available, I installed 

FSII counterbalance weights on my MKIII.  Have never had a hint of 

flutter since that day.



Don't know why we don't have flutter problems with the elevators, but 

as far as I know we don't.  There was some flutter problem with the 

early Twinstar elevator caused by the adjustable trim tab mechanism. 

One fatality is recorded because the trim tab cable attachment broke, 

or something to that effect.



I never had rudder occillation or flutter on the US and FS, however, I 

experienced it regularly with the MKIII.  Keeping my feet on the 

pedals was an early cure.  Then double springs on the rudder pedals 

fixed that problem on my MKIII.  Richard P used a counterbalance 

weight on his MKIII rudder.



john h

MKIII/912ULS

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

pj.ladd(at)btinternet.com
Guest

Posted: Mon Feb 20, 2006 8:58 am Post subject: Control Surface Flutter ????

I remember your nav light causing your rudder to flutter a bit,>>



Hi Michael,



here is a story about the ultimate rudder flutter.



During the war there was some experimentation with glider towing by a 

Lysander. A Lysander was a big monoplane. Parasol  wing (of odd shape) 

double strutted, fixed spatted (trousered)undercarriage. It had a massive 

radial engine and normally carried a crew of 2 in a long greenhouse. Because 

it could fly at very low speeds it was used for army cooperation and for 

dropping and recovering agents from fields in the dark in the Occupied 

Countries, often carrying 6 people in an emergency. It also had a large 

rudder.



Some bright spark decided that glider towing by Lysander in the dark was a 

good idea. In the dark the glider pilot couldn`t see where he was in 

relation to the tug so a large `L` shape with a light on it was fixed to the 

rear of the fuselage with the long leg of the `L` sticking up vertically 

just behind the rudder.



When this combination took off and airspeed increased, a bow wave of air 

built up ahead of the vertical bar and slammed the rudder of the Lysander 

hard over. This induced a violent sideslip and with the glider hanging on 

for dear life they were just about able to climb away into the darkness. The 

Lysander pilot managed to get both feet on one pedal and pushed as hard as 

he could. The rudder came straight, and then slammed over in the other 

direction.

In this fashion the pair managed to make a vast circle at little more than 

treetop height until they got close enough to the airfield again for the 

glider to cast off and land.  Relieved of the extra problem of the glider 

the Lysander pilot was able to climb a bit and he made another circuit and 

put the plane down.



What the pilot said to the boffin who dreamed up the idea is not recorded.



Pat 



--

Dave Bigelow

Joined: 29 Jan 2006
Posts: 103
Location: Kamuela, Hawaii

Posted: Tue Feb 21, 2006 1:01 pm Post subject: Re: Control Surface Flutter ????

A few years back, I did the first test flights of John Pitre's Twin Star on floats at Kaneohe Bay on Oahu.  Part of my checklist was to run the elevator trim full nose up and full nose down to check control stick pressure.  His particular Twinstar had a single cable that ran to one side of the trim tab control horn.  The other side of the control horn had a spring.  As you added nose down trim, the cable loosened and the spring pulled the tab up.  I don't know if this was standard from the plans.



Right after rolling the trim wheel full forward and slacking the cable, the aircraft started shaking violently.  I looked back and saw the elevator fluttering back and forth several inches very rapidly.  I rolled the trim wheel back nose up and the flutter stopped.  I have no doubt that the tail feathers would have failed in short order if the fluttering had not been stopped.



My take on this is that any movable trim tab on the elevator should be built in a manner where there is always a positive connection to the horn with no springs or bungees.  I'm not sure what would happen if the connection to the tab horn ever breaks or becomes disconnected, but I believe the chances of catastrophic flutter are high.

_________________
Dave Bigelow
Kamuela, Hawaii
FS2, HKS 700E

John Hauck

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

Posted: Tue Feb 21, 2006 3:33 pm Post subject: Re: Control Surface Flutter ????

Here's an NTSB report on a Twinstar fatality caused by elevator trim tab, controlable type:



http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001211X11253&key=1



However, this one was out of control.

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

slyck(at)frontiernet.net
Guest

Posted: Tue Feb 21, 2006 5:15 pm Post subject: Control Surface Flutter ????

I have the stock trim arrangement in my MkIII and it functions ok.

My problem is with inflight adjustments.  My seats are in the "wayback"

position making the trim lever unreachable.  I'm not about to move the 

seat.

I would  have to do some tinkering with the handle to get to actually

using it.  Last flight with ballast in the passenger seat I guessed at 

a couple

notches and lucked out with perfect trim.  Looks like I will stick 

calibration

marks for weight on the index bar.  -Any suggestions are welcome.

-BB



On 21, Feb 2006, at 6:33 PM, John Hauck wrote:



 	  Quote: 	
		   



 Here's an NTSB report on a Twinstar fatality caused by elevator trim 

 tab, controlable type:



 http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001211X11253&key=1



 However, this one was out of control.



 --------

 John Hauck

 MKIII/912ULS

 hauck's holler, alabama





 Read this topic online here:



 http://forums.matronics.com/viewtopic.php?p=13912#13912

jbhart(at)onlyinternet.ne
Guest

Posted: Tue Feb 21, 2006 7:10 pm Post subject: Control Surface Flutter ????

At 08:11 PM 2/21/06 -0500, you wrote:

 	  Quote: 	
		  



marks for weight on the index bar.  -Any suggestions are welcome.

-BB




	


Bob,



I like to use bungee cords, woven fish line, soft small bore aluminum tubing 

and guitar string tighteners for in flight aileron and elevator trim systems.



The history for development on my FireFly can be see at:



http://www.thirdshift.com/jack/firefly/firefly51.html



If the system fails there is no chance for control flutter.  It is very 

light.  The guitar string tighteners were free and came from a junk box at a 

musical instrument repair shop.



Jack B. Hart FF004

Winchester, IN

JetPilot

Joined: 10 Jan 2006
Posts: 1246

Posted: Tue Feb 21, 2006 8:23 pm Post subject: Re: Control Surface Flutter ????

 	  John Hauck wrote: 	
		  Here's an NTSB report on a Twinstar fatality caused by elevator trim tab, controlable type:



http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001211X11253&key=1



However, this one was out of control. 	


That is really scarey John...  Reading several stories like that and also reading about some very close calls with trim tabs causing severe flutter convinced me not to use trim tabs on my MK-III...  



Michael A. Bigelow

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

Kolb MK-III Xtra, 912-S

rrhoyt(at)ieee.org
Guest

Posted: Fri Feb 24, 2006 7:59 am Post subject: Control Surface Flutter ????

I have removed my factory designed trim and installed an elevator 

trim.  The reason for this was that the factory design trim provided 

positive feedback to the elevator control and that results in 

negative long term pitch stability.  The plane flies hands off the 

stick these days.



I also added an aileron trim to compensate for passenger and fuel 

imbalance.  I have counter balances on these control surfaces.



Ron



At 07:11 PM 2/21/2006, you wrote:

 	  Quote: 	
		  



I have the stock trim arrangement in my MkIII and it functions ok.

My problem is with inflight adjustments.  My seats are in the "wayback"

position making the trim lever unreachable.  I'm not about to move the

seat.

I would  have to do some tinkering with the handle to get to actually

using it.  Last flight with ballast in the passenger seat I guessed at

a couple

notches and lucked out with perfect trim.  Looks like I will stick

calibration

marks for weight on the index bar.  -Any suggestions are welcome.

-BB

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