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Old 10-28-2012 | 06:11 PM
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Recycled Flyer
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Default RE: FROG 80 Mk 1


ORIGINAL: qazimoto


ORIGINAL: Recycled Flyer


ORIGINAL: qazimoto
Chris, I can't quite see where the Frog thrustline could possible pass through the CG of the Red Wing.

Please explain.

Ray
Hi Ray,
when viewed from above draw the thrust line back through the wing, the original concept was for the thrust line to intersect the CG in order to eliminate the turning effect or yaw that such heavy out thrust would normally give.

Thanks.

P.S. Check the plan, the thrustline goes straight through the bell crank pivot also.


Chris,

I grasped the concept, and yes it's clear in the plan shown. However I just can't see the thrustline from the Frog in the pic above going anywhere near a reasonably placed CG for a c/l model.

Ray

Ok Ray, Ican supply a far higher resolution plan if need be but .......... on the plan there are two arrows, one directly in front of the front leadout and its matched pair on the opposite wing.

Draw a line between these and that is your centre of gravity pitch axis - according to the plan.

Draw a line down the thrust axis and note the intersection between the two lines.

The intersection is very, very close to the bell crank pivot.

The bell crank pivot is reasonably placed outboard to allow for the required tip wieght and represents the true 3D CG point.

Thats the whole point of the design mate.

( I can come visit Mannering Park around Christmas time to further elaborate!)

P.S. Iagree now, the pic of the model is deceptive indeed but bear in mind that all of these designs were deemed 'experimental' and thus most likely subject to change on a whim.

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