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Flying 442
06-12-2007, 01:55 PM
http://www.greatplanes.com/discontinued/gpma1380.html

Ok, I picked this up from someone who had it as a hanging model. I looked at the "convert to electric" info (gear drive), but after seeing this build and vid http://www.rcgroups.com/forums/showthread.php?t=263659
I'm still not sure. In the build, he talks about adding more throttle/power, but due to the mass/drag the speed almost stays the same past a point. I'm thinking of going with an E-Flite Power 46 because he's running 5 lipo's and my Power 46 planes run well on 5 lipos, but he's running a gear box and mine would be an outrunner.

Also not sure on the prop for this big bird. The Power 46 range = 12X8 ~ 14X10 and his gear drive setup works well on 13X6 ~ 14X6. Still the GP ad shows it being a 46~80 size, leaving me on the low end if I run a Power 46. This will be my first WW1 warbird and I should have it ready for flight by later today. Unless told otherwise I am planning on flying the Power 46 W/60 amp ESC and 5 4000mA lipos as soon as the wind is right.

P.S. The decals in the picture, are those to be left on there? Just seems like they take away from the scale look. I thought it was only on mine because it was a hanging display, but then I see it on this one too. Thanks for any help, Jon

Flying 442
06-18-2007, 02:06 PM
Ok, it will fly on an outrunner Power 46, 14X6 prop, and 5 lipo cells, just not to my (or it's) liking. I took it to the very start of the grass runway and gave it lots of runout. I put it in a slow turn about one mistake high and all was well. I backed to 1/2 throttle and it slowed to the point that if there was wind it would have stalled. Gave it 3/4th throttle and it was flying scale again. Tried to do a slow loop at full power and it stalled at the top making a very tight loop ending. All other scale moves went well, but needed full power to keep control.

It landed smooth and I checked everything out. Motor was very hot, but the ESC was the reg warm temp. The prop looks small on this plane, but 14X10 is max for this motor and anything over 14X6 went over the amp limit. I gave it one more flight at three mistakes high and gave it a workout. About 2 1/2 min into this flight the ESC shut the motor off and it dead sticked very well. On the ground the ESC was warm, but the motor was very, very hot with most of the flight 80% to 100% power.

If I could set it up to fly this way without motor stress it would be like flying an under-powered slow stick, I'm thinking under-powered for even scale looking flight, with dives needed in order to get speed up for a scale loop.

I know from past builds that a Power 60 will fix this right up and the larger prop (the P-60 can swing a 16X10) will look more scale on the front. I will be running a 6 cell w/2-3 packs with this motor, 3 ~ 4000mA cells per side. There is a nice place to fit them if you cut a hole throught the fire wall. This plane flys way too nice to be underpowered. The Power 60 will hit the nose weight needed to meet CG and the prop will look better too. It should come in at just over 9 lb with the Power 60.

I'm still getting the feel for this matching motors with planes thing and I only fly outrunners, so this may only help those in the same boat. The link above shows a gear drive that flew better than what I saw out of mine and after fine tuning he got his dialed in well.

All-in-all this is a great flying plane and if you fly other planes that like to nose over, the landings are no big deal with some extra up elev. I wish GP still sold these because the one I have came with a patched upper wing and a crack on both sides of the lower wing. Oh, it's also a traffic stopper as cars park on the road to watch it fly by! Hope this helps, Jon