Shawn Curry wrote:
Mark James Boyd wrote:

Say a Sparrowhawk and a Cirrus. Guess is the Cirrus will penetrate
better and hence be able to achieve longer flights in windy and / or
turbulent conditions?



Wow. Now THERE is an interesting question. How does a glider
with super stiff wings do going through turbulence vs. one
with flexing wings? I'd suspect the stiffer wings would
lose (they'd stall more cleanly instead of absorbing the impact)
but the difference may be too small to be important.

Any guesses on this one? This is pretty far out of my
field...

Don't think its stiff vs. flexy. Rather, how well laminar flow is
maintained (less drag) with less than perfect flow over the wings.
Apparently some airfoils do better than others. This belief with the
ASW-24 (which I've heard is suspect) probably cost more sales than
races. Why a Cirrus would be better than a Sparrowhawk in this regard
is beyond my understanding. BTW Ventii have very stiff wings and do
well in turbulence and headwinds.

Conjecturally Yours,
Shawn
I was wondering more about the differences in mass, rotational inertia, control
effectiveness...

Cirrus is a lot heavier than a sparrowhawk in percentage terms, so presumably
will tend to fly through minor turbulence with less upset.
Conversely Cirrus has lazy aileron response, so roll upsets take a little longer
with controls deflected - presumably less efficient.
Cirrus has all moving stabilisor - very powerful in pitch, and easy to get
unintentional pitch movements in rough air.
Cirrus wings are like rock - graphite 13% (?) wings on Sparrowhawk presumably
just shrug off a lot of what shakes the first generation glass ships.

Just idle wonderment on my part.
Never flown a Sparowhawk, have some vague idea that what makes a difference in
XC in my Cirrus is flying smoothly.

Cheers
Bruce