I read the paper by C. Horn and H. Fearn that Curtis Osterhoudt found for
us. In that paper, the authors describe how the release of the ball by the
quarterback exerts a slight downward torque on the rear of the ball
(pitching the nose up a bit) and also imparts a slight yaw to the right (for
right-handed quarterbacks).
I have a memory about throwing a football a different way, and if my memory
is correct, the ball does not turn its nose down to point along the
parabolic trajectory. I have not gone outside to see if my memory is
correct, because (1) I don't possess a football anymore and (2) I probably
don't have enough athletic ability anymore to throw the ball far enough with
this technique to see if it really keeps its nose up, and/or I would
probably injure my arm trying.
Anyway, I remember that if you throw a spiral pass underhanded (or perhaps
some would call this a "sidearm pass"... or maybe it is somewhere between
underhand and sidearm) , it keeps its nose up such as one would expect for a
spin-stabilized flight; that is, the angular momentum vector's direction
does not change during flight.
I am right handed. I started with my right arm roughly in the same position
as for starting a regular overhanded pass, but rather than initial forward
motion my arm travelled backwards then down somewhat like an underhanded
softball pitch, except the palm faced outward as my hand passed my thigh,
and I imparted clockwise spin to the ball (the same as it would have if
thrown overhand by a right-handed person). Although I could vary the angle
somewhat of the spin axis, I remember that I generally imparted a large
angle something like 45 degrees (spin-axis angle relative to horizontal). I
realize some old vivid memories are vividly wrong, but my old vivid memory
is that this type of pass pretty much kept its 45-degree angle for its whole
trajectory.
Does anyone else have this memory? Is there anybody out there with a good
enough arm to give this a try?
Michael D. Edmiston, Ph.D.
Professor of Chemistry and Physics
Bluffton University
1 University Drive
Bluffton, OH 45817
419.358.3270
edmiston@bluffton.edu