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Old Mar 23, 2008, 09:49 PM
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Richard Evans's Avatar
USA, TX, Canyon Lake
Joined Jul 2006
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Haoye J-10

I bought J-10 from RCEPOWER.COM (darkside212) and put it together (wasn't easy). I have just maidened it and it flew, actually kinda nice, but I had to hold nearly full up elevator. I even bounced it off the runway after takeoff, because I lowered the stick to the center position, not knowing it would rapidly nose down.

I took three quick test flights were I took off, went out and turned around and came back and landed. On flight two, I moved a lead weight I was using to try to get the CG futher rearward. This helped, but I still had to hold a good bit of up elevator.
on flight three, I added some elevator trim so that the control surfaces on the trailing edge of the wind had some built in "up". This also helped, but my best guess is that I shouldn't need that, and I just need to move the CG even further back. I also played with the offset and throw on the canard a little. It really slows up nice.

Once thing about the J-10 from Haoye, is that It came with no instructions or any CG measurement, only a cross hair symbol on a thumbnail view of the plane. I do have the CG about where that cross hair shows, but without measurements, it is just "eyeball it guesswork"

If I can get this thing to fly without holding elevator, I seems to fly very nice and with plenty of authority.
Note the nice high angle of attack during landing in the video.

here's the video:
http://www.rcgroups.com/forums/showt...62#post9412761


I haven't set up a delta wing with a canard before, so any advice will be very welcome.

Richard
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Last edited by Richard Evans; Mar 24, 2008 at 10:47 PM.
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Old Mar 23, 2008, 11:36 PM
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mongo's Avatar
midland, REPUBLIC of TEXAS
Joined Mar 2002
454 Posts
most deltas need a bit of reflex in the trailing edge, so up trimmed elevators/elevons is not too unusual.

where did you get the kit. what do ya think of the quality of the kit itself, instructions not outstanding i suppose.
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Old Mar 24, 2008, 03:33 AM
DominicM
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Fleet, Hampshire, UK.
Joined May 2003
2,368 Posts
I would guess CG still has to go further back then. Just try it in increments. It's not going to fly any worse that it did on that maiden flight. You handled it well. I don't know of any other foamie models with a working canard so this will sell well I think.

Found some info here. Looks like a big improvement on the quality of the Haoye F-18.

http://www.rcgroups.com/forums/showthread.php?t=818163
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Old Mar 24, 2008, 05:00 AM
UK Commercial RPAS Pilot
Scott Cuppello's Avatar
United Kingdom, England, Carlisle
Joined Mar 2007
2,596 Posts
The GWS J-10 has working canards, here's mine [it's on a 550w set up, 4s], C of G on this was 80-85mm from leading edge, wing measures 390mm, so maybe this comparison can give something to play with?
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Old Mar 24, 2008, 12:10 PM
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Richard Evans's Avatar
USA, TX, Canyon Lake
Joined Jul 2006
342 Posts
Thanks, that works out to about 21% or so Back from the leading edge, that might help. I'll look at that this evening.

richard

Quote:
Originally Posted by phoenix racing
The GWS J-10 has working canards, here's mine [it's on a 550w set up, 4s], C of G on this was 80-85mm from leading edge, wing measures 390mm, so maybe this comparison can give something to play with?
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Old Mar 24, 2008, 12:17 PM
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Richard Evans's Avatar
USA, TX, Canyon Lake
Joined Jul 2006
342 Posts
hey Mongo

I got it from darkside212, (WWW.RCEPOWER.COM)

The kit isn't easy to build and no instructions, I would say its a builders kit, you get the foam, and a very good 89mm fan powered by a outrunner and the hardware. The edf seems to be a great power system, and the foam looks pretty good.

The difficultys in assembling it involve bringing the two fuselage halves together with all the prerequisite sub assembly of servos, spars, canard, nose gear, wiring, fan installation and all ready and proper, because once it goes together, it would be too late to change anything.

Someone more patient than me could do a good job of making it look great.
Even if it doesn't look too great up close, it sure looks nice in the air!

I recommend it for someone that doesn't mind a building project.

Richard


Quote:
Originally Posted by mongo
most deltas need a bit of reflex in the trailing edge, so up trimmed elevators/elevons is not too unusual.

where did you get the kit. what do ya think of the quality of the kit itself, instructions not outstanding i suppose.
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Last edited by Richard Evans; Mar 24, 2008 at 12:58 PM.
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Old Mar 24, 2008, 01:27 PM
deltas are cool
AIR SALLY's Avatar
Tehachapi ,CA.
Joined Apr 2006
20,514 Posts
If i were you i would put some up in the canard(so the TE of canard goes down for up) this will help get some of the up trim out of your elev. also to put more reflex in the wing you can sand the lower side of the eleivons to the upper mold line ,this helps put reflex in the airfoil sand from about a inch and a half back from the TE.in a curved line ...your elev. will be thin at the aft edge but it will help ...you could glue some balsa Sq. stock to the TE and then sand it ..this will help the foam stay together,and offer some protection to the thin TE. just my 2 cents and move CG back slowly
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Old Mar 24, 2008, 05:57 PM
Effumall
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Joined Nov 2005
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Needing lots of up is an indication of a nose-heavy condition. Move the CG back.
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Old Mar 24, 2008, 08:51 PM
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Richard Evans's Avatar
USA, TX, Canyon Lake
Joined Jul 2006
342 Posts
Thanks for the suggestions

I've added some more weight to the tail and may employ some of the other ideas, I hope to test fly it again tommorrow.

I ran the power system using my Emeter tonight, but could'nt get a rpm reading with it in the duct, maybe I'll try to FFT analyse the sound pitch of the motor to figure the rpm. BTW, it is a 4 bladed rotor.

anyway at full throttle, it draws 38.2 amps at 12.6 volts. (482 watts)
I understand that the power system might take 4 cells, but It sure doesn't seem to need it!
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Old Mar 24, 2008, 09:12 PM
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Richard Evans's Avatar
USA, TX, Canyon Lake
Joined Jul 2006
342 Posts
GWS cg

The Haoye wing is 430mm at the chord. If I calculate where the CG is in with the same formula "chord length * .22" I get 94.6 mm from the leading edge.

that is way forward of where my CG is now!
that would suggest that my cg is too far back. That doesn't seem to be consistent with it wanting to nose down, I'm unsure though because it is a delta/ canard whcih I have no experience with. It did seem to get much better though when I moved the weight back.



Quote:
Originally Posted by phoenix racing
The GWS J-10 has working canards, here's mine [it's on a 550w set up, 4s], C of G on this was 80-85mm from leading edge, wing measures 390mm, so maybe this comparison can give something to play with?
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Old Mar 25, 2008, 05:05 AM
UK Commercial RPAS Pilot
Scott Cuppello's Avatar
United Kingdom, England, Carlisle
Joined Mar 2007
2,596 Posts
The canards are weird for sure, this is new for me too, on the GWS version, you have a moulding to align them with at the neutral position, is it the same on yours?
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Old Mar 25, 2008, 06:55 AM
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Richard Evans's Avatar
USA, TX, Canyon Lake
Joined Jul 2006
342 Posts
Yes, the same with the Haoye, right now, I have them aligned with a little up. (trailing edge down), I'll try setting them back to nuetral when I get it to where it doesn't want to nose down.

Quote:
Originally Posted by phoenix racing
The canards are weird for sure, this is new for me too, on the GWS version, you have a moulding to align them with at the neutral position, is it the same on yours?
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Old Mar 25, 2008, 03:52 PM
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Joined Aug 2006
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on my hobby lobby mirage 2000....

I always needed up elevon trim, even with moving the battery back and the the cg right on, it still wanted to nose down with no up trim, so I just live with it, up trim all the time, makes inverted flight tougher though. Guess it's just the delta wing design...
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Old Mar 25, 2008, 09:27 PM
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Richard Evans's Avatar
USA, TX, Canyon Lake
Joined Jul 2006
342 Posts
I made a quick test flight before work today, with more weight on the tail. whoops, too much I guess, it was tail heavy and very unstable. I was very lucky to get it back down in one piece.
next chance I will try again with less weight. seems to have a very small sweet spot.
thanks poochie for your report.


Quote:
Originally Posted by poochies
I always needed up elevon trim, even with moving the battery back and the the cg right on, it still wanted to nose down with no up trim, so I just live with it, up trim all the time, makes inverted flight tougher though. Guess it's just the delta wing design...
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Old Mar 25, 2008, 09:56 PM
NeArLy NoRmAl Al
Concord New Hampshire
Joined Aug 2005
32 Posts
CG Calc.

See if this site can help.
http://www.inlandsloperebels.com/Calc/cgcalc.html
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