Hi,
I just got a Tiger 60 ARF and would like to know to best way to balance this low wing trainer. It seems if I try to balance it right side up its almost impossible, and if I try with the plane upside down its more stable. So my question is, would it be ok to balance this plane upside down and acheive the correct balance?


Graham

Yes! Low wing airplanes are to be balanced upside down.

To balance a plane, the center of mass should be BELOW the wing. For a high wing airplane, that is right side up, for a low wing plane, that is upside down.

Kerry

Kerry is absoluted correct, low-wing planes are balanced upside down.

Ken

I have to admit my ignorance about his particular subject.
I've always been balancing my low wings upside down according to what everyone is saying. All of my low wings fly GREAT! Maybe I'm just lucky.

Yeah, what about a mid-winged plane, upside down or right side up? Or, maybe it doesn't make any difference.

For planes that are not stable on a CG stand you can safely use a sling. See the thread at http://www.rcuniverse.com/forum/m_17...tm.htm#1715012

Here is a detailed, yet simple to understand explaination of when and why you should balance upside down:

[link=http://www.rcuniverse.com/magazine/article_display.cfm?article_id=601]Balancing Upside-down[/link]

I've been using the sling method as mentioned in that link and it's very sensitive and accurate. But you must be sure the model is level because the pendulum weight is pointing at the true CG which is somewhere in the middle of the fuselage. If you have the wings level then it'll also show if the CG is offset either side of the fuselage centre line. If it is then you can determine exactly how much weight to add to a wingtip to get true lateral balance.

So true I also use the sling method and looks so cool hanging their. Four way balance all four corners also. Move the battery around on top of fuse and plane does not fall off CG balancer [:@]
Rich

Thanks for all the great advice. I will try it.

Graham

If the wing is in the middle of the fuse ,like a SHRIKE 10.
Do you balance on the top or bottom of the wing ??

In this case you balance so the majority of the weight is hanging below the wing. In the case of the Shrike you have the engine and vertical fins that extend up and place weight above the wing, so you would turn it over and balance it upside down.

Ken

OK, I'm a little confused about balancing mid-winged aircraft such as Extras, Edges, Giles, etc.
Let's say the engine is mounted horizontal for glow engines and mounted inverted for gas engines. Are they balanced upside down or right side up?

Regards,
doubledee

Don't think of it as "Right side up" or "Up side down"

Think of it as "Heavy side down"

Should I balance the Tiger 60 with it slightly nose heavy or should it be balanced evenly?


Graham

Even, OR slightly nose heavy (Very slightly - like 1 or 2 degrees) is always a good rule of thumb

What Minnflyer said!!!!

Ken

OK, so they should be balanced with the cockpit up as the heavy side of the aircraft is always going to be the under side of the aircraft as the landing gear, inverted engine, etc. are all located on the lower side of the longitudal centerline of the aircraft. Do I understand it correctly?

Regards,
doubledee

IF the lower half is the heavy side, then yes.

In the case of most mid-wing planes, the lower half WILL be the heavy side due to the fact that (As you said) the wheels, etc (Not to mention the radio) is below the wing