wrote:
I'm not sure why you'd cruise at 200 kts under
thermal soaring conditions, even when the lift is averaging 10+ knots,
which is quite rare. That kind of speed could be useful for XC in
wave, but that is a niche market based on my observations. I'm not
sure I'd optimize a design for that scenario if I wanted volume
production unless it didn't come at the expense of performance under
more mainstream soaring conditions.

The DuckHawk is not optimized for a 200 knot cruise - that's the Vne
number. Optimum cruise speeds would be a lot lower than that, but
significantly higher than current production racing class gliders, and
at a lower wing loading, so it can still have a good climb in thermals.

The material is a polycarbonate (like Lexan), quite tough, lighter, and
relatively easy to form compared to the thicker acrylic used on larger,
heavier, and faster gliders. It's a good choice for the SparrowHawk.

I was referring to what they might use on the DuckHawk in contrast to
the SparrowHawk. 200 knots is pretty fast to have a coke bottle for a
canopy - at least for me.

It sure is, and I'm sure Greg is aware that what works for a 120 knot
Vne may not be the best choice for a 200 knot Vne, and will choose
something appropriate. Still, I think you might not appreciate how tough
that canopy is, so try snapping a piece of Lexan )polycarbonate) and a
piece of Plexiglas (acrylic), and you will see why Lexan is used for
safety glasses.

I doubt that any glider depends on the strength of the canopy plastic to
absorb energy in a pinch!

I was talking about the fuselage which is quite thin - though I can
understand how you might have gotten confused because of the reference
to the canopy just before.

It's important to know he is *NOT* using a SparrowHawk fuselage for the
DuckHawk! He is using the same molds so the outside shape will be the
same, but the inside will be very, very different.

--
Eric Greenwell - Washington State, USA
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