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Old May 10, 2008, 06:35 PM
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Seawind maiden success... 1 thing I noticed?

First flight on my seawind was a success except that I lose control of the elevator during a large loop.

I set my travel to 120% and it helped a little.

My CG is at 35mm from LE still seems a little nose heavy.

Any sggestions?

Thanks for your help.
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Old May 11, 2008, 05:46 AM
Omphaloskeptic
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Joined Feb 2005
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I have the original Great Planes Seawind, with an electric conversion (E-Flite Power 60 motor), and never had any such problem.

What do you mean by "lose control of the elevator"?
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Old May 11, 2008, 07:38 AM
We shall serve the Lord
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Sounds like the air load in flight may have overloaded your elevator servo. Your CG may be too far forward also and you just ran out of travel to compensate. In my original review(http://www.rcgroups.com/forums/showthread.php?t=660997), I mentioned that you need 50+ oz-in of torque for the rudder and elevator servos. I originally used HS81MG servos for the rudder and elevator on my e-conversion. They seemed a little slow and when I put my hand on the elevator, I stalled the servo. I changed them out to 225MG servos and didn't have any more problems. Check out the review for how I set my CG and the dimensions. Hope this helps.
Blessings,
Mike McD
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Old May 11, 2008, 07:44 AM
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Quote:
Originally Posted by SaulOhio
I have the original Great Planes Seawind, with an electric conversion (E-Flite Power 60 motor), and never had any such problem.

What do you mean by "lose control of the elevator"?
Sorry, I should have stated it is the Foamie Seawind
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Old May 11, 2008, 03:26 PM
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The electric Seawind can kind of try to exit a loop early, when inverted, due to the high thrust line....upside down, with lower airspeed at the top of the loop, the high thrust line wants to make the model leave the loop by pitching down out of it.

Keep your airspeed up, and have enough elevator to overcome the effect of the high thrust line when inverted and all will be fine.
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Old May 11, 2008, 03:28 PM
Electric Coolhunter
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Quote:
Originally Posted by kingsflyer
Sounds like the air load in flight may have overloaded your elevator servo. Your CG may be too far forward also and you just ran out of travel to compensate. In my original review(http://www.rcgroups.com/forums/showthread.php?t=660997), I mentioned that you need 50+ oz-in of torque for the rudder and elevator servos. I originally used HS81MG servos for the rudder and elevator on my e-conversion. They seemed a little slow and when I put my hand on the elevator, I stalled the servo. I changed them out to 225MG servos and didn't have any more problems. Check out the review for how I set my CG and the dimensions. Hope this helps.
Blessings,
Mike McD
I have tons of flights on my Seawind with my mix of Hs-55s and similar 9 gram servos with no trouble at all......
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Old May 12, 2008, 02:29 PM
We shall serve the Lord
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Thomas,
My comments and the review I referenced was for the 71" fiberglass Great Planes Seawind. In my E-flite foam Seawind, I used the Futaba S3114 servos with great results, but most any small servo should work well.
Blessings,
Mike McD
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Old May 12, 2008, 06:24 PM
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On the foamie Seawind, the proper CG is to balance on the CF wing spar. Due to the pylon mounted motor location, sometimes at the top of a large loop, you will feel like you have lost up elevator as the loop seems to flatten out and more up elevator doesn't tighten up the loop. What has happened, is that the plane has slowed down and the torque due to the pylon mounted motor tends to push the nose "down" which is up at the top of a loop. You can see this same effect if you get low and slow and suddenly punch the throttle. The nose will drop until you get enough speed for the elevator to take effect.

Try outside loops, the pylon mounted motor helps tighten up the loops. Outside snap rolls and spins are spectacular for the same reason.

Blessings,
Mike McD
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Old May 12, 2008, 06:41 PM
Electric Coolhunter
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Quote:
Originally Posted by kingsflyer
On the foamie Seawind, the proper CG is to balance on the CF wing spar. Due to the pylon mounted motor location, sometimes at the top of a large loop, you will feel like you have lost up elevator as the loop seems to flatten out and more up elevator doesn't tighten up the loop. What has happened, is that the plane has slowed down and the torque due to the pylon mounted motor tends to push the nose "down" which is up at the top of a loop. You can see this same effect if you get low and slow and suddenly punch the throttle. The nose will drop until you get enough speed for the elevator to take effect.

Try outside loops, the pylon mounted motor helps tighten up the loops. Outside snap rolls and spins are spectacular for the same reason.

Blessings,
Mike McD
Pretty much what I told him, above...
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Old May 13, 2008, 03:26 AM
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I guess you did . It just takes me longer to say the same thing I guess. Sorry for the double info post.

We had three Seawinds at our recent float fly and all flew very well. I'm trying out an APC 8x6E prop on the stock Rimfire motor. I doesn't seem to make the same "stalled tip" noise as the stock prop during takeoff. Otherwise it seems to fly the same as the stock prop.


Blessings,
Mike McD
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Old May 13, 2008, 03:57 AM
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Thanks for all the great info! I will move the CG to the spar.

Question.....whats up with the stock prop. having the tips being bent in?

Thanks,
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