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Don Sims
10-17-2006, 03:00 AM
One of our new mwmbers sent me a PM asking what is the CG of the Easy Glider. I'm having a senior moment and can't recall. The weather here is nasty this evening so I won't be able to help him until after work tomorrow.

Any of you glider pros have an answer for him???

falingtrea
10-17-2006, 06:28 AM
The Multiplex USA website has instruction manuals available, but if it is similar to the electric version I believe it is 17mm behind the leading edge of the wings.

guest001
10-17-2006, 02:29 PM
78 mm behind the leading edge of the wing root or 5 mm forward of the rear of the spar box.:D

Up&Away
10-17-2006, 02:37 PM
According to the manual ( http://www.multiplexusa.com/Support/manuals/Planes/easygliderUS.pdf ) on page 7, 70mm from the LE at the wingroot.

guest001
10-17-2006, 03:30 PM
Opps! Sorry, but I misread it-I provided the Easy STAR CG spec! Too early!

falingtrea
10-17-2006, 04:03 PM
70mm from the LE at the wingroot.

That's what I get for relying on MY memory. :)

Don Sims
10-18-2006, 01:53 AM
Thanks gents! It was the 70 mm from the leading edge. You de man Up!

paulhealey
10-18-2006, 08:07 AM
the reason why i ask about the c of g for easyglider is that 70mm behind the leading edge is actually 1cm apprx BEHIND the main spar! this is the first plane ive built with the c of g like this.its common knowledge that a wing will not fly with the c of g behind the main spar.

Up&Away
10-31-2006, 09:01 AM
the reason why i ask about the c of g for easyglider is that 70mm behind the leading edge is actually 1cm apprx BEHIND the main spar! this is the first plane ive built with the c of g like this.its common knowledge that a wing will not fly with the c of g behind the main spar.
Common knowledge or not, I fly with the CG as per manual, and it is spot on. My EZG (and all 12 others that fly in my area) fly just fine. Maybe the common knowledge fact hasn't filtered through to here yet?

Deadstick 101
08-29-2008, 01:10 PM
So is much weight requied to get the CG correct? I have a Easy Fly ST330. So if I put the plane on a pencil, 70mm behind the front edge of the wings it should be close to being balanced?

Steve

zerts
09-04-2008, 03:17 PM
So is much weight requied to get the CG correct? I have a Easy Fly ST330. So if I put the plane on a pencil, 70mm behind the front edge of the wings it should be close to being balanced?

Steve

Unless you fly in windy conditions and want to ballast the plane with extra weight, try to avoid adding dead weight to balance the Easy Glider. The battery compartment is very long and located under the wing, so the battery location itself will help get the CG correct. But- it is difficult to remove a velcroed battery because you can't lift the battery up - I use a plastic knife jabbed in to separate the velcro.

The CG is largely influenced by your choice of motor and its weight, because the motor is so far away from the CG. My setup doesn't need extra dead load weight to balance it, but for instance the Multiplex EZGP "tuned" motor setup uses a heavy motor and they recommend adding the steel balls near the tail. Its best to do an approximate dryfit with all major components before gluing the fuse shells together to see if your CG is ballpark (advice for all foamie ARF's)

zerts
09-04-2008, 03:26 PM
the reason why i ask about the c of g for easyglider is that 70mm behind the leading edge is actually 1cm apprx BEHIND the main spar! this is the first plane ive built with the c of g like this.its common knowledge that a wing will not fly with the c of g behind the main spar.

I suspect that the model plane designers estimate the CG location to design in where the spar is located, and in the case of the EZG, they were off a bit. But the CG is so close to the spar I don't see any problem whatsoever. If the CG was radically far from the spar, I imagine the wing would twist and ultimately break, with the spar not so effective (if the wing was torture tested with a really large G-force).

daniel
09-04-2008, 06:00 PM
you mite want to put 32gram weight to the nose i put flaps on mine made from the roter blades off my protec heli with twin roater works well i glued them 10 cm from the body