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Old Sep 05, 2007, 06:53 PM
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CG Calculator with fuselage in or out

I took the Ga. Goose plans and ran the CoG Calculator using the full area of the wings vs only the area outside of the fuselage. Using the full area, the CoG moved forward by 0.260 inch or the same as 13% static margin instead of 10%. I believe I adopted the method of omitting the fuselage because my original design seemed nose heavy doing the bunny hop and the new figures moved the CoG back a little.You may play it safer by using the full area for maiden and then move the CoG back to 7% static margin. I do not care for 20 to 25% margin as some recommend. Low margin gives you more control up front before stall. Charles
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Old Sep 06, 2007, 01:55 PM
89" Kool Aid drinker.
Smash McCrash's Avatar
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Thanks LS. Planning on all HS55's, but 2 on the elevators.

Mike
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Old Sep 06, 2007, 11:10 PM
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Delivery delayed until Monday... Oh well. I think I am going to go with a EFlite Park 400 920kv outrunner with a 3 bladed Varioprop, 8.2" blades set to about 6" pitch. I get about 170W on 3S, so I think it should be good on the plane. What motor are you others using on the little Quickie 380?

Mike
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Old Sep 07, 2007, 09:41 AM
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I've heard that one person is using a LittleScreamers Purple Peril on an APC 7 inch prop but I'm using the Hobby Lobby Esskay 400XT on a 9x7 APC prop. My setup is pushing about 130 watts. I was going to use my Park 400 on it but I had not tried a 400xt so I decided to put that on the plane. The e-flite stick mount works great on this plane by the way. I tried the GWS one but it puts the motor to low. The e-flite one puts the motor dead smack in the middle of the cowl.

My plane came in at around 19 ounces RTF and balanced. If you can get it lighter I would recommend you do so. The manual states 17 ounces and I probably could have hit that if I had used lighter servos and a lighter battery. The Park400 should help you balance it out. The 400xt is pretty light and I had to add some dead weight.

Oh and feel free to add your build to the build thread if you want. There is almost 0 information on this plane out there so the more info the better.

http://www.rcgroups.com/forums/showthread.php?t=716004
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Old Sep 07, 2007, 11:11 AM
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Thanks for the info LS. I was about to ask about flying weight and power draw. The video of your's on 130W looks good, so the Park 400 should pull the plane around quite well.

Mike
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Old Sep 07, 2007, 04:28 PM
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Lost Soul, Your build log is a great job!. Thank you for sharing your adventures here. Did you mention a 60" Quickie? That would be more my speed. These fast small models tax my reflexes just a bit too much. I am pleased to see more canard models come onto the scene. I saw two in the last issue of Model Aviation. One was a glider and the other was a jet. Smash McCrash, welcome and please keep us posted on your progress. Charles
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Old Sep 08, 2007, 10:13 AM
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Starting to build the Depron Long EZ today,starting with engineering a steerable nose retract by modifying a GWS blue some how. Once I figure it out I'll start posting pics and info.Power will be a Eflite Park 370 1360kv propped to around 170 watts and 17 amps,I know it's pushing the motor a bit but in cooling airflow I have had one to 19 amps and 219 watts on a Thunder Tigre Velocity before.I'm taking advantage of this weekend for lots of building and some flying since I'll most likely be going back into the work force this week sometime.Servo's will be 3 or 4 s-75's(hs-55 equiv.) depending on the torque needed on the nosewheel retract.
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Old Sep 08, 2007, 02:11 PM
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Hi guys,

This appears to be a very well subscribed thread full of most interesting and innovative designs. I thought you may appreciate my own efforts. These are electric, canard and free flight. Yes, I let them go and let them do as they wish……..

Rezenebe : This is a Jim Fullarton design and I decided to go for broke and set it up with a GWS EDF50 ducted fan as it had been sitting on the shelf far too long and I wanted to see if I could tame a ducted fan for free flight. Power was by a 250 mah single cell LiPo and timed using a simple MOSFET timer. This is the only model that I launch upwards as if I get the launch angle wrong, the model just nods away until it reaches an equilibrium. It is a heavy weather Ebenezer and is very stable in pitch and yaw , far more than any conventional model that I own. It is also very quick , which is no surprise as the motor runs at > 3amps static……most impressive for a 12mm brushed budget motor. The model is no lightweight at 88gms and I get 8-10 30 sec runs before the battery needs pumping up. The wing loading on this model assures me that there is only a 1% chance of it being grabbed by a thermal. If it does then I make another as the model cost is only some £20.

Cekoadon : I built this from photographs on Colin Hutchinson’s website. IMHO it is the ugliest model I have ever seen with the strangest aerodynamic layout. It had to be built and was. I wish I could say that it flew off the board but it did not. It suffered undamped , unstable roll oscillations which were eventually corrected with increased foreplane area, dihedral, revised CoG and reduced decalage. This model should not fly, yet it does and very handsomely. It has a RobotBirds power train comprising ann HCS 40Watt outrunner and a budget Tower Pro ESC driven by a 3 cell 450 mah LiPo . The power taken by the motor and the motor run time is controlled by a PIC chip based FlytProf controller. The model weighs 160 gm and gives me 10-12 30 second flights before I need to charge the battery. The FlytProf system gives me a DT facility which I use to crack the rudder over to spin the model in. So far it has behaved itself and not tried to escape......but it will, it is of French heritage and has a mind of its own! (TIC).

There is something special about a canard , the way it sits in the air and the quite unexpected yaw and pitch stability offered by these two models. I will continue with their development and will post if there is any interest?

Regards Ian (UK)
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Old Sep 08, 2007, 02:16 PM
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Quote:
Originally Posted by boffin99
I will continue with their development and will post if there is any interest?
Ian,

I would say that among the frequent posters in this thread, there is definitely interest! Please, keep posting whatever you may be working on. I often have little to add to the thread, but always read what others share here. There is ample interest to be found here, of that I am quite certain.

Thanks for sharing your planes with us!
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Old Sep 08, 2007, 02:39 PM
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Ditto Magic 612 for me, Ian, and thank you for letting us know you are out there. Your models must be light to operate on the small cells. Do you ever catch a thermal and have to chase? I took five canards to the field this morning and kidded the glow guys because four of them were grounded with troubles getting them to run well.Yesterday, I took 3 models out and could only fly one because the wrong transmitter was taken. Oh well, the Long EZ was the one that flew so it made up for the other two. Charles
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Old Sep 13, 2007, 07:30 AM
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Ready for testing

The airframe is now completed. It is covered in Solarfilm, and the fuselage was brushed with Acrylic paint after sealing. It will get another coat of paint after I prove it to be airworthy. AUW is 430g (15.2oz).

I have setup flapperon mixing on my JR radio with some elevator>Flap mix. Although I am not using flaps, this mixing allows the ailerons to provide pitch control to complement the canard elevator. The mix proportion is so small the deflection of the ailerons due to elevator is barely visible. The ailerons are located on the outboard half of the wing, away from the downwash of the canard. It is setup so that 2/3 down elevator causes the ailerons move down to overcome the washout in the wing.

I will start testing with static margin somewhere between 7% and 10%. Before going for a maiden flight, I'll try some test glides without the motor fitted to reduce weight and the battery positioned to correct the CG.
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Last edited by John235; Sep 13, 2007 at 08:19 AM. Reason: Clarification about flap mixing
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Old Sep 13, 2007, 09:49 AM
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Virginia
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Richmodels does do a 40 size quickie. Not a bad price for it either. I know they have that 60 size long-ez as well.
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Old Sep 13, 2007, 10:51 AM
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That's a neat looking job, John! Best of luck with your testing.I do appreciate all your design effort and in keeping the weight low. You did well to cover the bottom surface before adding the servo because the heat applied after mounting the servo can cause the canopy glue to soften and if pressure is applied to the servo arm, it will come loose. I have had to remount at least two after trying to correct warps or trying to remove wrinkles. LS, thanks for the info on the canards at reduced prices. Some of our glow friends have a great chance to try one. Charles
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Old Sep 13, 2007, 02:48 PM
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guys, I'm looking at either the Long EZ-60 or Quickie 40 for a conversion soon.
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Old Sep 14, 2007, 08:55 PM
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Sydney, Australia
Joined Mar 2006
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Test success

This morning we had still air and good weather. I took the model down to my local park to do the test glides. By removing the motor and using a smaller 2 cell lipo, I got the weight down to 370g (13oz). The COG was set midway between the points marked on the fuse as 7% and 10% static margin. Because my last canard experience was such a disaster, I gave it a 50% chance that it was going to nose-in and snap something.

The test glides went really well. I did about 10 in total, each time moving further up the embankment on the edge of the park. It needed was a few clicks of up trim, but the deflection of the elevator at trimmed postion isn't very noticible. The whole time I never saw anything that looked like a stall. The landings were very gentle and graceful. It seems that on landing, the canard must have been partially stalled, since adding more up evelvator had no effect. I couldn't be happier with it, so I'm just going to put the motor back in and leave the setup exactly the same for the maiden flight. I intent to go to my club field on Wednesday if the weather will be good as forecast.

If anyone is looking at my layout and cg calculations, I'd should mention an error in the calculations I posted previously. I had the distance between the wing and canard as being too short, partly because of my calculation error and also because I added another 15mm (0.6") to the fuse length when I made the final drawings. The corrected version is included below.
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