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Old Feb 16, 2012, 03:07 AM
prefer lift over drag anyday
flyzguy's Avatar
Joined Jun 2005
168 Posts
Here's a few of my wings. The large pink foam and glass wings were 10 Ft, MH60, twisted for very nearly minimum induced drag. Recorded about 19:1 using an Attopilot integrating airspeed and averaging ground speed in a loiter circle. Would do a nice body free flutter mode about 80 km/hr. The small combat wing is a PW51 EPP wing with < 4oz/ft^2 and 4 degrees of washout retains energy very well. Covered with laminating film and painted.
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Old Feb 17, 2012, 07:07 PM
I bail out, anywhere, anytime
Taurus Flyer's Avatar
The Netherlands, OV, Almelo
Joined Nov 2010
2,958 Posts
Gents,

Always under development, (electro propulsion) but I still have the original construction photographs of ten years ago,

Own design Horten glider, 2,60 m.
All wood construction and silk and dope covering.

First picture to show the control elements and pushrods, before covering
Spoilers near the centre only on top.
Drag rudders, only on top of the wing.in the closed sections right side wing drag rudder is visible
Ailerons and elevators combined, so elevons.

The plane is conrolled with the use af a special controller device in the transmitter which calculates the postion of the drag rudders depending of elevator input and aileron input. There is always one rudder closed, or both in neutral position of rudder control,

Second photograph, close up.

Other pictures made in the Eiffel, Germany slope gliding.

Cees
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Old Feb 17, 2012, 07:44 PM
less is more
Knoll53's Avatar
United States, CA, Marina
Joined Sep 2006
2,852 Posts
Yea baby

I like the Taurus Flyer. That's one cool looking Horten! Looks like a very light buiild too. It must have been a trick to program the drag rudders to operate as they did.

Kent
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Old Feb 18, 2012, 04:57 AM
Deniable plausibility
Shedofdread's Avatar
Derbyshire, UK
Joined Aug 2008
2,316 Posts
Mmmm... Intriguing - the control system sounds most interesting. Lovely build as well
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Old Feb 18, 2012, 04:58 AM
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ohmite's Avatar
Eden NY
Joined Sep 2001
540 Posts
Quote:
Originally Posted by Taurus Flyer View Post
Gents,

The plane is conrolled with the use af a special controller device in the transmitter which calculates the postion of the drag rudders depending of elevator input and aileron input. There is always one rudder closed, or both in neutral position of rudder control,

Cees
Cees,
This glider looks very nice, impressive. Can you provide more information on the methods and principles of your rudder control device, or more pictures? Maybe a diagram that explains the principle? Did you find it more effective than elevon alone? Did these rudders allow you to using less washout?

Best Regards,
-Eric
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Old Feb 18, 2012, 06:11 AM
I bail out, anywhere, anytime
Taurus Flyer's Avatar
The Netherlands, OV, Almelo
Joined Nov 2010
2,958 Posts
Quote:
Originally Posted by ohmite View Post
Cees,
This glider looks very nice, impressive. Can you provide more information on the methods and principles of your rudder control device, or more pictures? Maybe a diagram that explains the principle? Did you find it more effective than elevon alone? Did these rudders allow you to using less washout?

Best Regards,
-Eric
Eric, gents,

Last question first. but I think it isn't new for you, only to complete the story.

Did these rudders allow you to using less washout?

Basicly for a Horten glider I personally don't like to talk about washout! Main reason for that is the Horten principle doesn't work without different AOA on several locations of the wing, It has to do with "basic design requirement"!!!

Just a way of talking but has to do with the reason: Why does the tip airfoil less AOA than the root and how much?

It all depends on, to create a bell shape lift schedule generating over the wing.
We all know but I need the complete story to answer the question!!!
So,


For which speed is an individual Horten designed?

Basicly the value of airspeed in which the lift of the tip is zero, cruise speed!
Too slow and the top has to generate lift. Too fast and the tip will generate negative lift.

But, that not only depends of airspeed, but also weight!! Yes indeed!

So, do dragrudders to allow me using less washout?
No at least not in thraight flight because both are closed and there isn't any difference in flying related with without.
Important in the principle, and that's why I did write it in the first post, both are closed in neutral position of rudder input.


Cees
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Old Feb 19, 2012, 09:52 AM
I bail out, anywhere, anytime
Taurus Flyer's Avatar
The Netherlands, OV, Almelo
Joined Nov 2010
2,958 Posts
Gents,
A short added note about the drag rudders.
The Horten was designed for two systems of the dragrudders.

First methode a mechanical mixer in the centre section.
Both elevons do have their local servo in the wing and two pushrods were used to activate the mixer in the centre secton, see the picture.

The mixer did eliminate the up and down input, only detected was the difference, so aileron action.
The aileron action did activate the right dragrudder to prevent (too much) adverse yaw. (left side pivot isn't visible but the same as right side.)
It is a fixed system and ratio, only to be changed by mechanical adjustment.
Flying the plane I discoved very less drag rudder deflection is needed to realize good control.

I did make a electronic mixer in my transmitter after that
A single servo is placed in the centre on same location as the mechanical mixer to activate the rudders
The amount of deflection was calculated in the transmitter and could be changed during flight by a ratio and zero adjustment.
Because I use an analog tranmitter (anti) logarithmic amplifiers are used for calculation.

My obeservation did show the second system give good curvature of turning.
Adjustment was experimental determined.

I never could compare the system with existing Hortens with same aspect ratio. I also never did fly without the system.
Goal of my experiments was, have a system that could be used and adjusted for Horten gliders with high values of aspect ratio like HO IV / HO VI and also to control slip of the plane with use of measurement and controller(s).

I did need the experiments to have an idea of dimensioning of rudders and deflection which is about 5 mm's max opening.

The Horten is in the workshop and In the future the plane will have electro propulsion and because of higher wing loading, redesigned tips with some more span and maybe combined with Schempp Hirth drag rudders.
Under development is also a slip measurement system.


Cees
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Last edited by Taurus Flyer; Feb 19, 2012 at 10:11 AM.
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Old Feb 19, 2012, 10:03 AM
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ohmite's Avatar
Eden NY
Joined Sep 2001
540 Posts
Cees,
Nice ingenious system. I'm sure with the microprocessors and sensors available now an onboard system with mixing and sensing should be much easier to implement. Thank you for the additional information.

Best Regards,
-Eric
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Old Feb 19, 2012, 10:25 AM
I bail out, anywhere, anytime
Taurus Flyer's Avatar
The Netherlands, OV, Almelo
Joined Nov 2010
2,958 Posts
.Eric,

Thanks for response,
I do fly "old school" so control systems are all analog for several reasons just as my construction methodes are "classic".
But, result can be the same.



Cees
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Last edited by Taurus Flyer; Feb 19, 2012 at 10:49 AM.
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Old Feb 19, 2012, 12:19 PM
less is more
Knoll53's Avatar
United States, CA, Marina
Joined Sep 2006
2,852 Posts
Hi Cees,

Really interesting mixer. I do have some questions regarding the linkage system though. Any additional comments, photos or drawings would be appreciated.


Quote:
Originally Posted by Taurus Flyer View Post
First methode a mechanical mixer in the centre section.
Both elevons do have their local servo in the wing and two pushrods were used to activate the mixer in the centre secton, see the picture.
So each elevon is operated by a conventional wing servo located at the elevon. Those elevon servos were also connected to the mixer at the center. So both the elevons servos drive the one mixer.


Quote:
Originally Posted by Taurus Flyer View Post
The mixer did eliminate the up and down input, only detected was the difference, so aileron action.
Right. If both servos pushed or pulled, as with elevator only control, the mixer would not move the drag rudders.
But here's the question. If with aileron input, one servo pushes and the other pulls, then the mixer will be offset to one side, causing both drag rudders to operate. One drag rudder linkage gets pushed and one gets pulled. That means one drag rudder would project above the wing and one would be drawn down into the wing.
That can't be what happened. What am I missing? Did you have some sort of one-way-only device at the drag rudder that eliminated movement from one direction?

Thanks,
Kent
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Last edited by Knoll53; Feb 19, 2012 at 12:25 PM.
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Old Feb 19, 2012, 02:12 PM
I bail out, anywhere, anytime
Taurus Flyer's Avatar
The Netherlands, OV, Almelo
Joined Nov 2010
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Ahhh Kent, you did make you message longer, so my drawing is a little bit "overdone". but, makes more clear for other members.

English isn't MY language, If it was my language I would have used pushpullrod for two directions, push and pull.
Using this way of formulation the drag rudder is activated by a pull rod and spring loaded.

The mechanical mixer was located near the TE in the center of the fuselage,
The drag rudder is right positioned on your picture, the other location in the wing is for the elevon servo.

Maybe you know, but principles of mixers like these we used in the past, in the first generation of proportional transmitters. for V-tails for example.

Now I did need a kind of "RE MIXER" with inverted action to generate an "aileron"
signal, because that is the result of the pull pull rods.
Because it was a temporary solution I did mix the aileron and elevator in the transmitter and remixed it back to ailerons for the drag rudders in the Horten.

All possible, because the Horten originally was a cuckoo-clock inside too (LOL)

Cees
.
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Old Feb 19, 2012, 03:06 PM
less is more
Knoll53's Avatar
United States, CA, Marina
Joined Sep 2006
2,852 Posts
Nice drawing Cees! I get it now. Push only at the drag rudder.

I really like the mechanical mixer. With modern ball links and proper geometry, I'm sure it can be very serviceable. Thus saving the precious Tx programming for other uses.

We have an old saying in this country (stolen from the Chinese, no doubt), " a picture is worth a thousand words".

A good drawing is worth much more.

Oh, and thanks for posting in MY language.

Kent
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Old Feb 21, 2012, 02:00 PM
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Kopenhagen
Joined Apr 2005
142 Posts
My Amokka

still going....the Amokka 2.0 is in the making

Yours Peter
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Old Feb 21, 2012, 02:29 PM
I don't like your altitude
Stupot46's Avatar
Joined Sep 2011
3,325 Posts
Quote:
Originally Posted by Peter Wick View Post
My Amokka

still going....the Amokka 2.0 is in the making

Yours Peter
What a beautiful place to to fly.Can you post some details on the plane please.
Regards Stuart
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Old Feb 22, 2012, 04:16 AM
Registered User
Kopenhagen
Joined Apr 2005
142 Posts
Dear Stuart

here is the (old) thread about the Amokka and a vid:
http://www.rcgroups.com/forums/showt...ghlight=amokka

the pictures here are from my last summer holidays in Danmark....and yes we rentet the house on the picture!!!!! Guess who made the choice :-)
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