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How do I set the CofG

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skyhawk newbie:
Hi to all...
I'm new here and new to flying ..
Just got meself a 4Ch SkyHawk Powered Glider..
http://cgi.ebay.com/New-4Ch-RTF-RC-EP-Aerobatic-TW742-SkyHawk-Glider-Plane_W0QQitemZ290326804731QQcategoryZ19164QQcmdZViewItemQQ_trksidZp3286.m7QQ_trkparmsZalgo%3DLVI%26itu%3DUCI%26otn%3D3%26po%3DLVI%26ps%3D63%26clkid%3D5078401181636134857
But I know you have to have a CofG for good glideing,but as the battery is held on with vercro , its not set for the CofG..
So how do I do it ...the vest and easyest way...  LOL

Thanks

Sean

Richard Boyd:
Hi Sean, is it possable for you to relocate your battery to make your CG in the correct position ?
You can add weight like small pieces of lead to position the CG correctly, but from my own personal experiances it is much better to move the battery or purchase a larger battery to give you the correct CG.
Hope this helps in some way,

Richard

Ron:
Hi Sean,

That's very good value isn't it?
All that stuff for 47 quid.

I'm guessing that maybe you mean where should the CofG be, as well as how to adjust it.

As Richard says, moving the battery is the best way to adjust it, but the position of the CofG should be marked either in the instructions of even possibly on the model itself.
One theory I've seen is that it should be about 24% of the wing chord back from the leading edge, and I'd say that position would give you a reasonable starting point.
Then it's glide tests in the proverbial 'long grass'.
But as the silage and hay season is well over, it might have to be heather and furze :(

skyhawk newbie:
Thanks for all replys...

Theres not alot of info in the manual,very basic..
Theres only 6 pages in the manual and the first 4 tell you how to put the glider together...the other 2 are about setting the Tx
The Prop is called a Airscrew ! ! !

Found out some more info on setting CofG
measure the wing from leading edge to trailing edge...(215mm) devide that by 4 (=53mm) then mark the wing back from leading edge....
Then devide the 215mm by 3 (=71mm) mark wing again...
Your left with two marks on the wing...
Set CofG ,slightly more to the front mark of the two on the wing for gliding...
think I've got this sorted...????
If this is the wrong / right way ..Please let me know....

Sean

Happy Days:
Yup, pretty much Sean, well done! :clap:

In case you didn’t know, the distance between the leading and trailing edge of a wing is called its Cord.
The centre of gravity of most planes is roughly between a quarter and a third of the chord back from the wings leading edge. :wink:  

For your first flight it’s safer to have the CoG a bit forward. So if I were you I’d set the model to balance on the forward mark.

In time, if you want to make the plane more aerobatic, you can move the CoG rearward, but generally your CoG should be somewhere between the two marks that you’ve made. :D

Keith

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