Vance Jaqua wrote:

Paul - I found what looks like a godd reference on
precession loads - in my first edition, seventh
impression Marks circa 1916 (no that was not when I
was in school)
the form Pb=(w/G)* k^2 * (PI*N/30)*(v*b)
P is force b is arm so should be foot pounds moment
w is wt in lbs and G is our old friend 32.17
k is radius of gyration of the "flywheel" typ about
1/2 radius
N is rpm which with pi and 30 I think makes this
radians per sec too
v is peripheral precession velocity fps times our arm
which makes it omega radians per second
a quick check on a 10 lb 6 ft prop at 2700 rpm
with 1 radian per second pitch or yaw (about 57
degrees in a second) fairly quick - puts out about 198
ft lbs which is a pretty small bending moment.
attached are scans from the text - see if you pry out
answers in the same ball park? -Vance
OK to "run it up the public flag and see who salutes"
as they say

 
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