thrust line for engine and not mounting engine on this thrust line
The likely outcome is that
you will have a bird with some strange and possibly unpredictable ways.
Center of lift also moves around a good bit depending on AOA, airspeed,
load, type of airfoil, etc. And its movement is non-linear. Otto
Lilienthal suspected this and I think there was a discussion of it in
his book. Octave Chanute and Wilbur Wright debated it at great length
in 1901, and its in thier letters. And finally, Wilbur and Orville
discovered just how much it can move, and in what odd unexpected ways,
when they conducted the wind-tunnel experiments in 1901.
For a real-world demonstration of what happens when you screw up your
CG calculations, check out the Stormy Petrel 3:
hometown.aol.com/wright1902glider/page3.html Interesting how it can
balance itself on the downtubes without any tie-downs, and yet it can't
lift off and blow away in a 30mph wind? When I static tested it 3 weeks
after this photo, I found that the actual CG was 23" behind the
hang-point. Opps.
Harry
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