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Sep 05, 2019, 12:21 PM
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Kenneth Paine's Avatar
Quote:
Originally Posted by hotfly
What's the benefit of top-drive flaps anyhow?? Is it to reduce drag because the servo arm is internal? …
Justin
Martin Hepperle of MH airfoils fame has posted on his website Dr. Würz's study of the impact of external linkages. I can't get a direct link to the relevant page because of the way he has coded his own website http://www.mh-aerotools.de/airfoils/ . Click the "Aerodynamics" button on the left margin and then click "Drag of Linkages with Pushrods" from the top right hand box on the aerodynamics page.


The long and short of the research is that the exposed linkages on a four servo wing adds about as much drag as an extra stab. There are interesting diagrams on the web page.
Last edited by Kenneth Paine; Sep 06, 2019 at 10:34 AM. Reason: error
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Sep 06, 2019, 10:31 AM
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Brynmr's Avatar
I sanded down the nose (maybe 5mm or so) of my 3M Osprey to fit Art Hobby's 35mm spinner. A Pete Hoeve motor mount completed the nose build. Pretty cool - I love Art Hobby spinners.
Sep 07, 2019, 02:51 PM
DS will change your life
SpeedsterDEN's Avatar
Thread OP
Odyssey at the beach


Odyssey 2,7 m crusing at the dunes (3 min 28 sec)


Cheers
Soren
Sep 10, 2019, 08:22 PM
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I maidened the Odyssey this evening. It was a busy night at home so I only got about 15 minutes to sneak away and have one short flight, but I am happy with the result. This thing moves fast under power! It glides OK but it felt a little sluggish, I suspect it needs the cg tweaked a bit. Also seemed to lose a lot of altitude in turns if it was banked steeply at all, which might just need some trimming to solve. Tested crow, worked great but needed some down elevator trim and possibly more up aileron (flaps are nearly at 90 degrees so they're OK). From watching Soren's videos I know this thing can be a sweet flyer once it's set up right!

All in all a great first flight. Hoping to get back out soon. Sorry no pics or video, didn't have enough time to fiddle with any of that!
Sep 11, 2019, 02:44 AM
Registered User
Quote:
Originally Posted by dwizum
I maidened the Odyssey this evening. It was a busy night at home so I only got about 15 minutes to sneak away and have one short flight, but I am happy with the result. This thing moves fast under power! It glides OK but it felt a little sluggish, I suspect it needs the cg tweaked a bit. Also seemed to lose a lot of altitude in turns if it was banked steeply at all, which might just need some trimming to solve. Tested crow, worked great but needed some down elevator trim and possibly more up aileron (flaps are nearly at 90 degrees so they're OK). From watching Soren's videos I know this thing can be a sweet flyer once it's set up right!

All in all a great first flight. Hoping to get back out soon. Sorry no pics or video, didn't have enough time to fiddle with any of that!
Hi Dwizum,
I found my Adventure sluggish particularly on the rudder on my first outing. In fact I would have gone as far to say it seemed practically non existent on the first few flights...... having played with the COG rearward a little and in my case tweeking the elevator incidence...... I mostly use elevator and rudder for most of the turn and adjust bank with the ailerons. Now I'm getting used to how it wants to fly I'm finding it more and more nimble.....
Regards Michael
Sep 11, 2019, 05:18 AM
Registered User
It seems like a constant theme in this thread that people end up with a CG rearward of the recommended location. I already have a bit of lead in the tail to get it to 80mm (against the recommended 78mm). I may try to go back to 85 and see how that feels next time out.

And my altitude loss in turns is probably lack of pilot coordination. I need to do some turns close in so I can keep an eye on the nose and see if it needs a different technique or some different trim settings. Last night, out of habit, I was basically doing "bank and yank" turns with just aileron and elevator, and in a tight turn it would just lose altitude - it wasn't stalling, just dropping quick. I may need to give it some down elevator before the turn to gain speed, or use more rudder and less aileron.
Sep 11, 2019, 07:49 AM
DS will change your life
SpeedsterDEN's Avatar
Thread OP
I have see some new pilots in my RC club trying to fly the Odyssey without using the rudder and they also lusing much height in the turns.
The Odyssey and even more the Silent need the rudder to fly a nice thermal circle.
And it don’t work to make a aileron to rudder mix due to in a thermal you sometime fly with opposite aileron to fly a flat turn, and then you really will lose height
Soren
Last edited by SpeedsterDEN; Sep 11, 2019 at 07:54 AM.
Sep 11, 2019, 03:38 PM
Registered User
Thanks for the feedback. I'm going to play with the rudder more the next time I get it flying for sure.
Sep 12, 2019, 05:02 PM
Aom
Aom
Registered User
I finished some exams recently at my uni so i thought i'd celebrate with a new plane!

My buddy wanted one also so he got the tigra and i got the zuni.
We are going to fly on the slope only.

Does the aileron hinge go full-span on the zuni? Is it wort to do this mod or does it fly well as is?
I was choosing between the zuni or skua, but i already have a skua-like plane, so whatever, if im not happy i can get another arthobby plane when i finish some more exams
Sep 17, 2019, 08:27 PM
Registered User
I flew the odyssey again today. It seems like my problem was partially my lack of manual rudder input, but also the aileron differential. I tried more differential and got better performance. With the new aileron configuration and some rudder input I can now turn nice and flat, but I need to give it some down elevator at the start, when first banking into a turn, to keep it from slowing too much and getting mushy. I may have too much aileron differential now, but it's better than it was. I don't think I'm trimmed too slow in general because it really moves along during level flight.
Sep 18, 2019, 09:39 PM
Boar? I'm a Thermal Pig!
Batmanwpg's Avatar
dwizum
I think you may need to move the CG back a bit more. I've never had to add down elevator to initiate a turn. One thing I also did was to have rudder as master and aileron as slave in a mix. I found it gave much flatter turns when I really needed to keep it flat. I did find the Odessey was fairly sensitive to using the aileron for turning.
Sep 19, 2019, 08:40 PM
Registered User
Quote:
Originally Posted by dwizum
I flew the odyssey again today. It seems like my problem was partially my lack of manual rudder input, but also the aileron differential. I tried more differential and got better performance. With the new aileron configuration and some rudder input I can now turn nice and flat, but I need to give it some down elevator at the start, when first banking into a turn, to keep it from slowing too much and getting mushy. I may have too much aileron differential now, but it's better than it was. I don't think I'm trimmed too slow in general because it really moves along during level flight.

I'm curious to read what you get up to with your tuning Dwizum .....
Sep 20, 2019, 08:41 AM
LOOK UP
cbfsoar15's Avatar
Quote:
Originally Posted by Batmanwpg
dwizum
I think you may need to move the CG back a bit more. I've never had to add down elevator to initiate a turn. One thing I also did was to have rudder as master and aileron as slave in a mix. I found it gave much flatter turns when I really needed to keep it flat. I did find the Odessey was fairly sensitive to using the aileron for turning.
Im not sure why you are trying to keep the turn flat? wouldn't you need to cross control to do that. if so that's more drag. how about a coordinated turn.

Me John 09 17 2019 (20 min 43 sec)
Sep 26, 2019, 12:40 PM
Aom
Aom
Registered User
Okay!

Received the Zuni V 1.2 M some day ago, and im blown away by the finish of the kit already. The wings dont have spars ( i thought all the models used their carbon glass balsa spar) but they do seem stiff and very light! Will be tremendous fun on the slope and with histart maybe too!

I got the art hobby laquer with the model, is there any good advice you guys can give for this process?
Never done this before... After the laquer has dries i have some hobbyking covering film transluscent yellow and or purple that i wish to apply, would it stick and look ok, or should i paint instead? Same goes for the tail, its just 2mm balsa so i think it would become somewhat stronger if i can cover it all nicely..

Any zuni owners here?
Sep 26, 2019, 01:44 PM
DS will change your life
SpeedsterDEN's Avatar
Thread OP
Quote:
Originally Posted by Aom
Okay!

Received the Zuni V 1.2 M some day ago, and im blown away by the finish of the kit already. The wings dont have spars ( i thought all the models used their carbon glass balsa spar) but they do seem stiff and very light! Will be tremendous fun on the slope and with histart maybe too!

I got the art hobby laquer with the model, is there any good advice you guys can give for this process?
Never done this before... After the laquer has dries i have some hobbyking covering film transluscent yellow and or purple that i wish to apply, would it stick and look ok, or should i paint instead? Same goes for the tail, its just 2mm balsa so i think it would become somewhat stronger if i can cover it all nicely..

Any zuni owners here?
Spray it first with 1:1 water and alcohol and let it dry, then sand it smooth before you give it lacquer, then sand and lacquer and sand again and you have a nice wing, and don't lacquer where the epoxy and fiberglass shall be for the wing assembly.

Good luck

Soren


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