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View Full Version : Discussion using ccpm mix on tail rudder surface on airplane?


XarvoX
Dec 06, 2006, 08:24 PM
The basic idea: using 120° angled tailplane surfaces mixed with ccpm mixer for elevator and rudder, but also to control aileron.

if you take a look at the tail on the F-4 Phantom (http://www.ugamedia.com/f4/logo2.jpg) you should get the idea :)

Ive been planning a long-term balsa project, and would like something technicly different.. :)

i figured i could try a 3-wing zagi prehaps or some sort of canard-type craft, but the basic functionality has to be at least ok..
it could also be extended to a X-wing ie the famous starfighter :D

So i wonder, has anybody done something like this previously?
the mixing shouldnt be a problem, just got a futaba 9c.
but how are the flight-tendencies?

i will be building from scratch for the first time, so any helpful links/hints/suggestions would be great :)

Just got a Futaba 9C and a dedicated hobby-room with huge build-potential and i just MUST use it :D ;)

Sparky Paul
Dec 06, 2006, 09:49 PM
CCPM involves 3 servos.. there's aileron, elevator, and throttle.
Moving the throttle moves the aileron and elevator at the -same- time.
You're better off using rudder-vator mixing for the horizontal, with aileron seperate.

yoyoML
Dec 07, 2006, 05:37 AM
i figured i could try a 3-wing zagi prehaps or some sort of canard-type craft, but the basic functionality has to be at least ok..
it could also be extended to a X-wing ie the famous starfighter :D


3-wing Zagi? You mean Lambda Shuttle, don't you? Give me a B-Wing, too!!!

XarvoX
Dec 07, 2006, 06:35 AM
with normal pitch-ajustment on standard ccpm, every servo goes the same direction.
Meaning, if you mount 3 servos for 3 surfaces and change pitch, you get aileron (screwing)
but since i dont want to change pitch with throttle-stick, i will still have to make my own mixers.

what im thinking of is a fully articulated flight behaviour with only 3 rudder surfaces, witch i think is the smaller of problems compaired to the tx mix..

and sparky, have a look at the align trex with ccpm, there´s 3 servos for cyclic plus throttle.. :) (left/right aileron+elevator)

Sparky Paul
Dec 07, 2006, 10:48 AM
Here's another unconventional airplane.
This is Tim's "Thing"... Cute but...
I can see using a CCPM transmitter on a vee-tail or elevon -glider-.. no motor.
I've set one up just to see if it would work.
The collective mixing screws things up.

Ledbetter
Dec 07, 2006, 11:41 AM
It's 4 channels isn't it?

Throttle, pitch, roll and elevator.

You could make that work using pitch to control main wing reflex, for example.

Sparky Paul
Dec 07, 2006, 12:18 PM
It's 4 channels isn't it?

Throttle, pitch, roll and elevator.

You could make that work using pitch to control main wing reflex, for example.
.
Throttle and pitch on one stick.. the collective, in helicopter parlance.
Any movement of the collective moves the aileron (lateral cyclic) and elevator (pitch cyclic) in one direction at the same time in a CCPM system.
Moving the cyclic would move the elevons/ruddervators as well.
That's why I specified a glider. 2 channels.
Rudder (pedal) changes the tail rotor speed for yawing.

XarvoX
Dec 07, 2006, 12:50 PM
im sorry if im not clear enough in my description, i dont intend to use a stock ccpm mix, but to emulate one with a few free mixes. the result will move the Y-shaped tail-surfaces in much same fasion as a eccpm swashplate.

the idea is to attatch the servos in the same way on all surfaces so when all servos push/pull, i get aileron effect, when two move up/down i get elevator, and when 3 working together forms rudder.

i hope this straightens your questionmarks :)


the Lambda Shuttle seems like a good candidate :D ;)