Help with Graupner Super Air
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Help with Graupner Super Air
I have some questions on the CG...
I've read the review on this here, this prompted me to buy it. The review said the CG was set at 4 1/4", but it needs a little more AFT.
The instructions, which are now available in English, say to start at 3.54" (90 mm) or 4" (100) for the experienced.
In order for me to get the CG to 90 mm (3.54"), I must add about 14 oz. to the nose...this seems a bit heavy.
I am using a .40 size motor, not the .46 size, so this may be part of it.
Anyway, just wondering if anyone else has some suggestions on the CG.
I've read the review on this here, this prompted me to buy it. The review said the CG was set at 4 1/4", but it needs a little more AFT.
The instructions, which are now available in English, say to start at 3.54" (90 mm) or 4" (100) for the experienced.
In order for me to get the CG to 90 mm (3.54"), I must add about 14 oz. to the nose...this seems a bit heavy.
I am using a .40 size motor, not the .46 size, so this may be part of it.
Anyway, just wondering if anyone else has some suggestions on the CG.
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Help with CG
Well, I must be only the second person to buy this! Let me ask the question another way.
I must add about 10 - 14 oz of lead to the front of the plane to get the CG correct.
Does this seem a little much for an ARF?
Also, when I check the CG, there is NO fuel in the fuel tank. The fuel tank is positioned ahead of the CG.
How do you check CG, with gas or without gas?
Jeff
I must add about 10 - 14 oz of lead to the front of the plane to get the CG correct.
Does this seem a little much for an ARF?
Also, when I check the CG, there is NO fuel in the fuel tank. The fuel tank is positioned ahead of the CG.
How do you check CG, with gas or without gas?
Jeff
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Help with Graupner Super Air
Always without fuel. And yes, 10-14 oz is too much. Try to move as much stuff forward as possible. And I don't think a .46 will be better. .46 engines are usually just as heavy or even lighter as a .40. If adding lead I suggest you put it as far forward as you can. Try to get it at the inside of the firewall.
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Help with Graupner Super Air
Thanks Perminator,
I thought it a bit much too. The only problem is that this is an ARF, without 'tearing it apart' and rebuilding, I really can't move anything else more forward. At least, I can't think of any way to do this.
I'm wondering if the recommended CG is off.
Without any adjustment, I'm at 5" - the recommended is 3.5 to 4"
Jeff
I thought it a bit much too. The only problem is that this is an ARF, without 'tearing it apart' and rebuilding, I really can't move anything else more forward. At least, I can't think of any way to do this.
I'm wondering if the recommended CG is off.
Without any adjustment, I'm at 5" - the recommended is 3.5 to 4"
Jeff
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Help with Graupner Super Air
On a constant chord wing you could start with balancing on the spar. Also you can calculate about 25-30% of the chord and start there. 10-14oz. seems a little high for a 40 sized plane unless the servos are too far back or the battery is not under the fuel tank. You could always break the servo tray loose and remount it farther forward.
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Help with Graupner Super Air
I have this plane also and was confused about how to balance it, so I just put it together and flew it. Not very scientific, but it worked fine. I have an OS .46 with the reciever and battery mounted directly behind the gas tank. It is nose heavy in this configuration, so I'm going to move the battery pack behind the cockpit and see what happens. I will go home tonight and see where it is actually balancing. It is a nice flying plane and looks great in the air.
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Thanks nickster2
I'm very interested in where you have it balanced. I haven't flown mine yet (too cold), but all of the calculations indicate the CG should be around 4".
My plane weighs around 5 lbs 14 oz. I'd be interested in how much your plane weighs as well.
How long have you had your Super Air?
Do you use the flaps as well?
Take care,
Jeff
My plane weighs around 5 lbs 14 oz. I'd be interested in how much your plane weighs as well.
How long have you had your Super Air?
Do you use the flaps as well?
Take care,
Jeff