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On Wed, 19 Aug 2009 14:07:24 -0400, "Peter Dohm"
wrote:

"Stealth Pilot" wrote in message
.. .
On Mon, 17 Aug 2009 14:11:58 -0400, "Morgans"
wrote:



btw Jim. I have a computed drag curve for the tailwind. you will know
the classic diagram of induced and parasitic drag that has induced
reducing in a curve to nothing while parasitic increases in a curve to
maximum. the plot of resultant drag sits above the crossed lines as a
U shape. it's a classic representation.
for the W8 tailwind that classic U shape is centred on 80 knots.
what that means is that on approach if you slow down to 60 knots you
get in the area of rapidly increasing sink (which is why you approach
at 70 knots) you havent just entered the "back side of the drag
curve", you've always been in it. At 65 knots you are entering the
vertical part of the left side of the U. at 70 knots you are at the
bottom left corner. tailwinds *are* happiest flying fast.

Stealth Pilot

The tailwind is amoung the all time standouts in low parasitic drag, and the
rapid rise of induced drag above the stall contributes to the short field
landing performance. I lack any personal experience, but have been told
that the short field performance is excellent.

Peter


if you want to really impress the pundits in a Tailwind.
you give it the gun, tail up and hold it there. normally Takeoff
Safety Speed is 57 knots but the tyres are rated to 120 knots, so you
accelerate holding it on until 80 knots. you do this solo btw.
then as you pass through 80 knots with full throttle you gently but
firmly rotate into a steep climb. you can hold this to 250ft
thereabouts at which time you bunt back to a more gentle takeoff
profile.

what the pundits see from the ground is just an apparently normal
takeoff, the speed differences not being that noticeable.
the climb out though would beat the pants of any damned ultralight!

the original builder of my aircraft was sitting beside our clubhouse
one day chatting when I did this. he was utterly stunned that the
tailwind had such dynamic takeoff performance.
"oh you made my day. she went up like a homesick angel"

....it is all technique born of knowledge.
I've owned the W8 Tailwind now for 10 years and I wouldnt trade it for
the world. once you get used to them they are a magic aeroplane.

landing speed I have no idea on. you never never never look inside the
cockpit during flare out. never.
on grass I'm stopped half way along a 600m strip most of the time.
Stealth Pilot