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scb28
04-17-2006, 02:57 AM
Can anybody tell me where along the wing the CG is supposed to be measured on a GWS Tiger Moth. The instructions say 0-10mm from the leading edge of the lower wing. But the wings sweep back enough so it definitely makes a difference where along the wing the measurement is taken. Any help will be greatly appreciated. Thanks

firemanbill
04-17-2006, 03:04 AM
Can't say for certain since I don't have a tm, but it is generally taken right at the fuse. At least that's how I do it anyway...

and welcome to WF by the way...

qban_flyer
04-17-2006, 03:38 AM
Can anybody tell me where along the wing the CG is supposed to be measured on a GWS Tiger Moth. The instructions say 0-10mm from the leading edge of the lower wing. But the wings sweep back enough so it definitely makes a difference where along the wing the measurement is taken. Any help will be greatly appreciated. ThanksMy T/M is going on strong still after over 500 flights on it and six motors later. 10mm is the correct measurement for the CG, while it doesn't make much difference where it is within that range, it is imperative to have the model upside down when checking its CG. It is impossible to do with it rightside up. Matter of fact that's the way to do it with low wing models as well. :)

firemanbill
04-17-2006, 03:42 AM
oh yeah, forgot about the turning it over part. Qban, would it still measured up against the fuse or out a bit?

scb28
04-17-2006, 03:45 AM
So then I balance it right at the fuselage 10mm back from the leading edge of the lower wing?

firemanbill
04-17-2006, 03:48 AM
Yes, with it turned upside down.

scb28
04-17-2006, 03:54 AM
Thanks for the info. I think CG is pretty close now but I'll check again. I plan to test fly the Moth soon...if this California weather ever clears up. It's been raining, seems like forever. Thanks again.

qban_flyer
04-17-2006, 04:01 AM
Thanks for the info. I think CG is pretty close now but I'll check again. I plan to test fly the Moth soon...if this California weather ever clears up. It's been raining, seems like forever. Thanks again.Up against the fuselage, and in reality it makes no difference to the plane if it is a bit forward or aft of the determined point.

I flew mine today with different size Li-Pos, some weighed 40 grams, some 45 grams while others were 50 grams. All sat in the same spot, the T/M didn't care, It just flew. :D

whizzard
04-17-2006, 03:44 PM
I found that the CG on my TM was right if I just picked up the plane by the trailing edge of the upper wing at the wing cockpit cutout notch and it balanced there it would fly nice.

Bill

Heightisgood
04-19-2006, 03:20 PM
Up against the fuselage, and in reality it makes no difference to the plane if it is a bit forward or aft of the determined point.

I flew mine today with different size Li-Pos, some weighed 40 grams, some 45 grams while others were 50 grams. All sat in the same spot, the T/M didn't care, It just flew. :D

Qban's right. I fly with a couple different LiPos and the CG is really quite forgiving. I can fly a 2 cell 1320 and fly for over half an hour easily. Compared to most of my other crazed :eek: planes the T/M is probably the most relaxing plane I have.

<Jeff

qban_flyer
04-19-2006, 05:40 PM
Qban's right. I fly with a couple different LiPos and the CG is really quite forgiving. I can fly a 2 cell 1320 and fly for over half an hour easily. Compared to most of my other crazed :eek: planes the T/M is probably the most relaxing plane I have.

<JeffI'll second that! :)

Old Fart
04-19-2006, 05:59 PM
Just changed mine out to a 2025-4200/11x7, we'll see how she flies on Friday :)

scb28
04-22-2006, 03:50 AM
Finally got some good weather. I've flown the Moth 5 or 6 times so far. My CG is in the visinity of what everybody recommended. One way it's a little nose heavy and another way it's a little tail heavy. It doesn't seem to make much difference though, it flies great. I'm using a little 100watt brushless motor on a GWS ep350 size gearbox at 5.33/1 and a 2000ma2s battery. Like I said it flies great. As somebody mentioned the landing gear is definetly a weak point though. It broke off while I was just taxiing. I reinforced it with some light plywood and it the problem is solved. Other than that it's kind of like flying a slow stick but with ailerons. Very relaxing. Thanks again for everybody's input.

Here's a picture of the Moth

Twmaster
04-22-2006, 04:35 AM
Nice looking Moth Steve.

Old Fart
04-22-2006, 08:34 PM
Just changed mine out to a 2025-4200/11x7, we'll see how she flies on Friday :)

Here I go replying to myself :)

2025-4200/11x17 flies AWESOME. I had about a 15 mph wind - the plane will _accelerate_ into the wind. Used full power for takeoff and once or twice on climbs (will go vertical) - other than that maybe 1/2 throttle. Flew almost 20 minutes - still had some of the 3s/1300mAh left over (nerver hit soft cut)

scb28
04-23-2006, 06:30 AM
Jeff,

Sounds like you have a real performer. I was thinking of more power for the Moth but I'm worried that it might blow the wings off or something.
I think I'll save the higher powered outrunner for something designed for it. Good luck with yours.