 |
Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
|
| View previous topic :: View next topic |
| Author |
Message |
victorbravo(at)sbcglobal.
Guest
|
 Posted: Tue Jun 13, 2017 1:04 pm Post subject: Strange Flying characteristics of new to me Mark III clasic |
 |
|
One or more Kolbers has pointed to the flaps as a possible reason for the problems we had. This may be the problem... does the following make sense to the experienced Kolbers??? :
Let's say that the airplane was not built perfectly straight, and it wanted to roll one way (like many homebuilts).
One owner installed the "adjustable" U-joint on one side of the fuselage on this aircraft, hoping to trim out the problem that way.
The same owner, or perhaps a subsequent owner, tried to adjust one of the wing flaps a little more up or down, still trying to solve the problem.
But because the flaps are hinged directly to the aileron torque tubes, adjusting the flap will have an unfortunate side effect of inducing different forces on the ailerons as well.
If one flap has been adjusted downward (attempt to trim airplane to fly straight), then when the stick is moved in that direction the pilot has to use more force, because the pilot is pushing that FLAP down into the airstream more than he has to push the other flap.
Jimmy removed the adjustable U-joint and replaced it with the standard U-joint, on advice from the factory. This may have also taken out HALF of the previous corrective efforts to trim the airplane.
Does this make sense to any of you? Have any of you seen Kolbs where the owner tried to adjust the flaps in order to correct a wing issue?
Bill Berle
www.ezflaphandle.com - safety & performance upgrade for light aircraft
www.grantstar.net - winning proposals for non-profit and for-profit entities
| | - The Matronics Kolb-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kolb-List |
|
|
|
| Back to top |
|
 |
John Hauck
Joined: 09 Jan 2006
Posts: 4639
Location: Titus, Alabama (hauck's holler)
|
| Posted: Tue Jun 13, 2017 2:18 pm Post subject: Strange Flying characteristics of new to me Mark III clasic |
|
|
If the aircraft was mine and I had all those problems, I'd start from scratch, insure the aircraft was built correctly, had not been modified (especially the control system), and everything was rigged as specified in the plans and instructions. I would insure I was starting my journey from a standard beginning.
Once I got it back to standard configuration, then I would test fly it, insuring I did the test flight alone, not with a passenger on board. If I wasn't an experienced MKIII pilot, I'd find one that was to do my test flying. He would know what to expect from the MKIII in flight.
If I still encountered the same problems, I'd put the standard (large) rudder trim tab on temporarily. It can be attached with Gorilla Tape to test fly. Sometimes the rudder trim tab will correct adverse roll problems, when your mind is telling you that it is aileron or wing incidence problems.
Always change only one thing at a time. After each change, test fly to see what that change has affected.
I would not change thrust line in any way, unless it has been modified. Then I would change it back to what it should be per the instructions. The thrust lines on Kolb aircraft, all models, are correct the way they were designed and fabricated. Incorrect thrust lines would not affect the aircrafts flight characteristic as described unless you mounted the engine backwards.
I would not try to trim the aircraft with flap(s).
Aileron trim tabs are effective for slight roll problems, not the problems you all describe.
I test flew the latest model MKIII Extra. It demonstrated similar characteristics. Wanted to fly straight if it was allowed to roll 10 to 15 degrees to the right. Was a terrible, unnatural feeling. Took a Hell of a lot of left stick to fly it straight and level, but was happy flying rolled right. This flight was without a rudder trim tab. We installed the large rudder trim tab, test flew, and the problem was gone. Hard for me to grasp, but it worked.
These are my thoughts and experiences. It is the way I would do it. I am not recommending anyone else try this at home.
John h
Fayetteville, NC
--
| | - The Matronics Kolb-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kolb-List |
|
_________________
John Hauck
MKIII/912ULS
hauck's holler
Titus, Alabama |
|
| Back to top |
|
|
neilsenrm(at)gmail.com
Guest
|
| Posted: Tue Jun 13, 2017 4:38 pm Post subject: Strange Flying characteristics of new to me Mark III clasic |
|
|
Jimmy
I agree with John H make sure the plane is built to specifications first.
Bill
I disagree 100%. Kolb airplanes never have control issues if they are built correctly. That being said they are built by builders of all skill levels. So to say it in a more technical way, shit happens.
Rick Neilsen
Redrive VW Powered MKIIIC
On Tue, Jun 13, 2017 at 7:03 PM, Bill Berle <victorbravo(at)sbcglobal.net (victorbravo(at)sbcglobal.net)> wrote:
[quote]--> Kolb-List message posted by: Bill Berle <victorbravo(at)sbcglobal.net (victorbravo(at)sbcglobal.net)>
That is very helpful, thank you for taking time to respond.
Over and above the potential causes and fixes for this, another thing I am getting out of all this discussion is that significant aileron system issues (control heaviness, asymmetrical loads and high required force) is not seen as being rare or abnormal for a Kolb.
As a suggestion, I will advise Jimmy O'Neal to find the original Kolb rigging and control setup specifications and start by making sure that this is all set back to the factory specs. That way he will know where he is starting from.
I will also advise him to make a proper series of measurements to determine whether there is a warp, twist, or other "big picture" issue with the aircraft.
As far as resolving the high force to actuate the aileron system, does anyone on the Kolb list know whether the aerobatic style "spades" that were developed for one Kolb actually solved this problem? It seems like a lot of effort and modification, but I also know that these spades do work (on aerobatic aircraft and for a different intended purpose).
Bill Berle
www.ezflaphandle.com - safety & performance upgrade for light aircraft
www.grantstar.net - winning proposals for non-profit and for-profit entities
--------------------------------------------
On Tue, 6/13/17, John Hauck <jhauck(at)elmore.rr.com (jhauck(at)elmore.rr.com)> wrote:
Subject: RE: Re: Strange Flying characteristics of new to me Mark III clasic
To: kolb-list(at)matronics.com (kolb-list(at)matronics.com)
Date: Tuesday, June 13, 2017, 3:45 PM
--> Kolb-List message posted by: "John
Hauck" <jhauck(at)elmore.rr.com (jhauck(at)elmore.rr.com)>
In my experience it was lack of an
adequate trim tab, if all else was rigged to specs and the
control system had not been changed or modified.
The aircraft I was flying was much
easier to roll right than left.
John h
mkIII
Fayetteville, NC
--
| | - The Matronics Kolb-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kolb-List |
|
|
|
| Back to top |
|
|
ceengland7(at)gmail.com
Guest
|
| Posted: Tue Jun 13, 2017 5:41 pm Post subject: Strange Flying characteristics of new to me Mark III clasic |
|
|
On 6/13/2017 2:55 PM, Ralph B wrote:
| Quote: |
Along with the U-joints, there is also the offset fin. This was installed by the builder and I don't see how I would do without it. I've also included a picture of the adjustable rudder trim tab. Between the U-joints, offset fin, and rudder trim tab, the Kolbra can fly hands off in calm air. For pitch trim, the builder installed a motorized bungee windup to move the stick forward or aft. It is controlled with a toggle switch for nose up or down trim.
Ralph B
--------
Ralph B
Kolb Kolbra 912uls
N20386
550 hours
Clever ideas, but a couple of questions.
|
1st, no safety wire on that turnbuckle?
2nd, what's to keep those little shackles on the horizontal stabs from
going overcenter & moving the leading edge up instead of down?
Charlie
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
| | - The Matronics Kolb-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?Kolb-List |
|
|
|
| Back to top |
|
|
|
|
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum
|
Powered by phpBB © 2001, 2005 phpBB Group
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
