>Use a Javelin throw, and enough "up" preset on a spring-loaded toggle switch >to
>rotate HARD from the near-level or slightly down angle you release the
>plane at, to vertical as instantly as possible. The plane should "park"
>nearly over your head, NOT out in front (much).
You want to pull up fast, but not "as instantly as possible".
Two reasons:
1) The induced drag energy loss in the pullup goes up with
the g's pulled, so there is an optimum turn radius. For
a typical HLG a 20-25 ft pullup radius is optimum.
2) Energy is extracted from the wind when the path curves
upward in the presence of headwind. If there is a wind gradient
(and there usually is), a larger radius pullup will see more
path curvature higher up where the headwind is stronger.
If the glider enters the larger wind while already going vertical,
the additional wind doesn't do any good.
I fly at Davis Field in Sudbury MA which often has a noticable
wind shear at about 30 ft up due to surrounding dense trees.
The best trajectory seems to be a rather sedate pullup so that
the glider punches through the shear layer at about a 45 deg
angle rather than vertically.
--
- Mark Drela
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