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Old Sep 30, 2011, 01:10 AM
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Yeah it feels clearly nose heavy, and I have even moved the battery tray back, plus I mount my 1500 mAh battery far back on it. Might be able to move the velcro back and move the battery even farther though.

I know some of you use 2200 mAh batterys, it must be crazy nose heavy? Needs much added weight in the tail?
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Old Sep 30, 2011, 01:26 AM
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Originally Posted by Freddan View Post
Yeah it feels clearly nose heavy, and I have even moved the battery tray back, plus I mount my 1500 mAh battery far back on it. Might be able to move the velcro back and move the battery even farther though.

I know some of you use 2200 mAh batterys, it must be crazy nose heavy? Needs much added weight in the tail?
Even while it was still all stock, except for the ESC (I never had the courage to use that thing with 6 servos), my Phoenix was always nose heavy. With a 2200mAh 3S I had to tape 30g worth of coins to the tail just to achieve some semblance of balance. In the end I took the coins off and went with a 1300mAh battery instead. Totally different aeroplane in that configuration. Instead of dropping its nose as soon as you let off the power, it would glide very well, though I'm far from an expert in extracting high performance.

With a bigger motor I had to move the battery tray backwards. Now I'm thinking of moving the servo tray too, to explore traumkumy's suggestion of a CG in the 80+ range.
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Old Sep 30, 2011, 01:27 AM
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Originally Posted by Freddan View Post
Yeah it feels clearly nose heavy, and I have even moved the battery tray back, plus I mount my 1500 mAh battery far back on it. Might be able to move the velcro back and move the battery even farther though.

I know some of you use 2200 mAh batterys, it must be crazy nose heavy? Needs much added weight in the tail?
Just buy a 2200mAh Li-Po..

The Phoenix is a Glider and there for , should be flown like one...

If the want a full acro glider, buy something else...


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Old Sep 30, 2011, 02:07 AM
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skyhawk:
What do you mean? Is a glider supposed to be heavy? Or nose heavy? I donīt know what I want I just wanted to try "gliding", but Iīm not that into it yet so I donīt know the difference. Yesterday it was late and almost no wind at all and I find that kinda boring. Just floating around... naah. The nicest thing of every flight was coming down fast and low and hearing the "swoosh". And then doing a new motor run to get up to altitude so I can do it again.

I would love to be able to catch some thermals someday as that was mostly what I was interested in when I bought the Phoenix. But I haven't been able to fly it much this summer.

I have 1300's, 1500's and 2200's but 2200 feels too heavy in my mind. I will try the 1300 mAh's though and see if it makes any difference to the CG.
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Old Sep 30, 2011, 02:21 AM
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Originally Posted by Freddan View Post
skyhawk:
What do you mean? Is a glider supposed to be heavy? Or nose heavy? I donīt know what I want I just wanted to try "gliding", but Iīm not that into it yet so I donīt know the difference. Yesterday it was late and almost no wind at all and I find that kinda boring. Just floating around... naah. The nicest thing of every flight was coming down fast and low and hearing the "swoosh". And then doing a new motor run to get up to altitude so I can do it again.

I would love to be able to catch some thermals someday as that was mostly what I was interested in when I bought the Phoenix. But I haven't been able to fly it much this summer.

I have 1300's, 1500's and 2200's but 2200 feels too heavy in my mind. I will try the 1300 mAh's though and see if it makes any difference to the CG.
BarnOwl is the Guy you want for thermaling his Phoenix...
Floating is what you want stay up there all day..


Me I mainly Slope mine ,so there for, I want it nose heavy..


What have you set the CG at...
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Old Sep 30, 2011, 02:22 AM
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A glider is supposed to be well balanced, like every flying machines
80mm GC is 3% (common case), thermal soaring should be around 4~5%, accrobatics & 3D are 0~1%. 70mm was 9%.

And as the wing a realitivly thin (compared to an esayglider for example) I suppose it must fly quite fast to have good effyciency of the aifoil.

Will post pics of my new layout later this day.
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Old Sep 30, 2011, 02:32 AM
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Originally Posted by H2SO4 View Post
Even while it was still all stock, except for the ESC (I never had the courage to use that thing with 6 servos), my Phoenix was always nose heavy. With a 2200mAh 3S I had to tape 30g worth of coins to the tail just to achieve some semblance of balance. In the end I took the coins off and went with a 1300mAh battery instead. Totally different aeroplane in that configuration. Instead of dropping its nose as soon as you let off the power, it would glide very well, though I'm far from an expert in extracting high performance.

With a bigger motor I had to move the battery tray backwards. Now I'm thinking of moving the servo tray too, to explore traumkumy's suggestion of a CG in the 80+ range.
I bought my version of the Phoenix with the flaps already installed. I have clocked up over 100 flights with the standard motor and servos though I did have to replace the ESC after landing in a dam. I also had to rebuild the battery tray after destroying it in a couple of early nosedives. The lightest plywood I could lay my hands on was twice the weight of the original. I also fly with a 2200mAh 3s lipo.

I fly it as a glider which for me means launch, climb to altitude, turn of motor, search for thermals, GLIDE down. My average flight lasts 40 minutes with 5-6 climbs on the motor, though on good thermalling days my neck gives out before the battery. The motor is rarely on for more than 30-40 secs.

Early on, I was having trouble getting the plane to fly straight and level without a fair bit of up elevator and attributed this to the extra weight affecting the CG. I messed around moving the battery back and forth without getting the results I wanted. Eventually I tried trimming the elevator to compensate and it was a huge sucess. The plane became more agile and improved even more when I moved everything back to their original positions. I now find that I only need to make minor positioning changes when I use a lighter 1500mAh battery

I found this article http://www.vfss.org/index.php?option...cles&Itemid=67 to be extremely helpful in setting it up properly. I've attached some photos to show my current positioning of the 2200mAh battery and "neutral" elevator position. I've also included a shot of the my velcro solution for holding the canopy on. It requires making a couple of small slits in the fuselage but looks a lot better than the rubber band I used to use.
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Old Sep 30, 2011, 03:15 AM
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The Manual says...

The ideal C.G position in 70mm +/- 5mm


So set it for 70mm with one of your batteries ,
Elevator must be level in neutral position...take it for a fly see what it's like..

I have two friends that I go slopeing with,they both have a Pixel acro glider,both are very good glider pilots , there is 15mm diff in the C.G's points on each of there gliders...One can not fly the others glider,because of how the other has set his C.G point...


I could say ..yeah set at 70mm ,will flys like a dream...
another guy would say no not 70mm , set it at 80mm will flys like a dream...
then someone else will come along and say ,no your both wrong, mine is set at 60mm and flys like a dream......

It's all about what you feel is right...

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Old Sep 30, 2011, 03:39 AM
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You are right the feeling is really important.
But it's not everything, because underside there are real physical constraints.

For exemple: If you like an nose-heavy setup, why not, but you will have to conpensate this nose weight with some elevator lift. This elevator lift will cause drag, and this drag will reduce the global effeciency of the glider.
On the phoenix there is no need to lift the elevator because the angle between wing and stab is already really high with 4,3° where soaring setup are more around 2,5° and 3D 0°. So the elevator is not trimed, but the drag is present.

So ok if "you" like it with standard setup, and aren't really concerned by taking the best advantage of your material, don't touch anything, fly, and just enjoy it. Otherwise try differents ways.

For me it's part of the fun to try to make this 50$ chinese foam flying like a hi-spec glider and there is some potential. (But tbh, my road will be reaaaaaaaally long to have a proper setup and a proper flying level )
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Old Sep 30, 2011, 03:46 AM
Heli's and gliders, what else?
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Nederland, GE, Slijk-Ewijk
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Originally Posted by Ken_Jungles View Post
I've also included a shot of the my velcro solution for holding the canopy on. It requires making a couple of small slits in the fuselage but looks a lot better than the rubber band I used to use.
I like that! I use two rare earth magnets now but this is a way better solution!

I also have the CG at exact 70mm. With a 1300 battery you should trim it at the stock cg spots (marked on the underside). It's thermalling like an Eagle! (If weather permits......)
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Old Sep 30, 2011, 04:18 AM
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I donīt have the measurment of my current CG in my head, but I balanced it on my fingertips yesterday before flying and it came in probably about 5-6 mm in front of the marked cg location on the underside of the wing.

Under full power it climbs almost vertically in a very short time so it feels really nose heavy. And the slightest speed I happen to gain while power off gliding makes it climb right away. Iīm gonna measure my CG tonight and Iīll probably end up trying lighter batteries and/or adding weight to tail to se what difference it makes in the air.
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Old Sep 30, 2011, 04:53 AM
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Buy a C.G balancer ...

Best thing I ever did..
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Old Sep 30, 2011, 05:35 AM
Heli's and gliders, what else?
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Or make one....pretty easy.
Here's my balancing Phoenix. You see the two marks just behing the wooden spar on the bottom of the wing? (pic2).
Or don't they come with them anymore?
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Old Sep 30, 2011, 05:48 AM
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Originally Posted by BarnOwl View Post
Or make one....pretty easy.
Here's my balancing Phoenix. You see the two marks just behing the wooden spar on the bottom of the wing? (pic2).
Or don't they come with them anymore?
Even better

Do as BarnOwl has done , saves you money ..


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Old Sep 30, 2011, 06:05 AM
Heli's and gliders, what else?
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It's pretty darn good weather here for the time of the year, so I took it out for a spin this morning.
But as soon as we arrived the wind started blowing again, so no thermals.
I had two runs of about 10 minutes on one pack. Not bad though after that wet summer of ours!
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