T E A M
Hi all, need some help on zagi. I am flying a zagi but I have some problems with it. At normal speed I can control it very well but when I throttle it more then 30% it starts to gain attitude and stall after a while. Then it nose diveand keep spinning. Now matter how I counter alierons or pull up the evelator it does not respond, after which it crash. Can anyone help? Is it set up or controls?? How can I prevent this? Been crashing all the flights with the same problem. I have no problem with the rest of my plans like e-starter or easystar. Appreciate if someone can guide me along...
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Sounds like you used under powered servos for the job or flimsy flight control linkages.
More informations will help like your motor setup/ radio equipment and actual model make. Is your model a Genuine Zagi from Trick R/C or any other flying wing that people generally regard as Zagi? -
Also may be up thrust. Check if your propeller shaft is point up. For Zagi, it should be no more than 1.5 degrees to the wing chord line (imaginary line draw straight from the middle of the leading edge to the trailing edge of the wing)
If zagi glides nicely with power off but pitches up propotionally to throttle, it is almost sure to be up thrust. Just reposition your motor to point lower.
The other percularity of flying wing is that the CG is more fwd that conventional plane. It should be round about 20% Mean chord as oppose to about 33% on conventional plane. If it glides normally with power of, the CG is correct meaning probably its the up thrust. If it doesnt glide move cg fwd. Proper cg on wing would need the elevon to have slight pitch up above neutral when gliding constant speed with no elevator input.
hope this helps.
cheers
KevinComment
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Hi thanks both. This is my model.
I am using the same servo and motor as stated. Checked servo linkage and servo strenght it is work well, checkEd motor is at neutral point, not point up or down.
I got a strong feeling it has to do with my hands. Normally what do u guys do when the plane stall and nose dive? I close throttle and pull up but when it spins I cannot get it to repond already. Should I open throttle and let every thing be neutral for it to regain glide? Btw the cg is correct the plane can glide very ncely w/o throttle.Comment
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Does the wing glide very slow w/o power?
Once any plane goes full stall, do not do anything until the nose points down and the aircraft accelerates for a short while. This will ensure the airflow is re-established on top surface of both wings sufficiently before recovery is carried out. In the case of a spin, recovery procedure: power idle, all controls neutral with opposite rudder (opposite to the direction of spin), once the wings stop rolling, pull up slowly, and reintroduce power.
For wings it is the same if you have rudder, if not, recovery is tricky. throttle cut, let the nose drop and gain some speed, aileron to stop roll and pull up slowly. Looking at the picture of the wing, the fin seem a little too big, this may induce spiral.
When establish in a spin, flight control in not effective, some airplane cannot recover from a fully developed spin without the aid of spin recovery device, eg spin chute. Therefore the best is to recognise on set of stall and dont get into full stall which may developed into spin.
If your plane is pitching up with power, use elevon to pitch it down, if you have full down elevon and it is still pitching, reduce power. If your tx can do mixing, mix elevon to throttle (elevator fuction). This will enable flat acceleration without pitching up when you open throttle.
happy experimenting
KevinComment
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Thank you!! I will try again I think it is my hands, controls of this plane is very sensitive, maybe I increase the exponential and reduce the d/r to help to bring down the swing. Yes, the wing glide very slowly.Comment
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keith, that's a nice foamy "Zagi" plane you got there. Cheap also.
Does Jethobby have any more stock?Comment
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They should still have, you can check with themComment
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Hi Keith,
Did you manage to get your Aoxan "Zagi" flying well?
I bought one from Ch******* the same as the one from Jet Hobby.
I have two problems, where is the CG and what motor is suitable?
I bought this motor but feels a bit underpowered and acting funny.
Which motor you are using?
I dug out the foam to put the battery far forward. Then I tried throwing it without power and it immediately nosed in.Comment
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Hi Keith,
Did you manage to get your Aoxan "Zagi" flying well?
I bought one from Ch******* the same as the one from Jet Hobby.
I have two problems, where is the CG and what motor is suitable?
I bought this motor but feels a bit underpowered and acting funny. Which motor you are using?
I dug out the foam to put the battery far forward. Then I tried throwing it without power and it immediately nosed in.Comment
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Is this correct?
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Two problems on the zagi wing you have :
1)The trust line of the motor is wrong need to be till with little angle because as you power more than 30%, the wing nose heading up. It must fly in level flight as speed increases. (wrong C.G on the zagi wing will cause the model to fly with the nose up dwn, up dwn like dophine fish). C.G. far back will keep flat spin. Nose heavy will have to keep pulling up elevator or very much up trim.
2)Is a wing tip is giving you a problem , when it come to stall it will spin with no control. Is a tip stall. I flew and experiment with my zagi wing and many people have this problem with wing and I solve it with this solution.
To solve this to place a tip fin at the end of the zagi tip top extended to bottom. |------O------| it will look like this is the front view. So when the zagi turn the wing tip will still support and not produce vortex and stall.
I have flew my Zagi wing in the fleld with very slow speed and also at high speed. Also at gliding speed (zero power) in the field, so much so that people in the field say my wing is so easy to fly.
Keith4896, Do Modify and do this I am sure the solution will work for you. All you need is 1 inch on the top and botton , phone card or coroplast will help.
May Show how tip stall is like on a plane ...Comment
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refer reading material - wing tip vortices
picture on airbus A319
reading on wingtip device/vortices.
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Hi Zennith,Originally posted by zennith View Post
I dunno about Keith whether his problem has been solved?
I haven't flown mine yet.
Good idea for the wing tips. I'll make it from Coroplast.
Should I leave out the stock vertical fins? Does it contribute to unwanted spins?
EtmanComment
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Etman / Keith
This is free flight in wind tunnel. about the experiment of what I did on my zagi wing and is proof to be good in flying.
Watch the video
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