50+:1 15m sailplanes

Ian Strachan wrote:
Our vaches may not be very vicious but our roads (for retrieving) are

But didn't the ``vaches folles'' (=mad cow) start out in the UK??

SCNR ;-)
-Gerhard

In article , Eric Greenwell
writes
JJ Sinclair wrote:
"There is a substitute for span, it's called skill, but you can buy
span"
OK, it's 7:00 PM, the sky has been completely overcast for hours,
you have
5000 feet and your looking at a 50 mile final glide. Now SKILL your way home.

You don't grasp the concept, JJ: with skill, the pilot is 50 miles out
at 6 pm, not 7 pm, and gets home just before all the lift dies.

Since I can't buy skill either, I bought a motor.

Even better, a motor AND good L/D. Gap-crossing can be needed any time,
not necessarily after 6 PM !

--
Ian Strachan
Gap Crossing Country (UK)

Eric wrote
Since I can't buy skill either, I bought a motor.


Now, Now, Eric we don't want to start that *motor* argument again, do we?
JJ Sinclair

Iam wrote.
Even better, a motor AND good L/D. Gap-crossing can be needed any time,
not necessarily after 6 PM !


Now, Now, Ian we don't want to start that *motor glider* vs *pure glider*
discussion again, do we?

JJ Sinclair

In article , JJ Sinclair
writes
Iam wrote.
Even better, a motor AND good L/D. Gap-crossing can be needed any time,
not necessarily after 6 PM !


Now, Now, Ian we don't want to start that *motor glider* vs *pure glider*
discussion again, do we?

I meant gap crossing by L/D, not by motor, as I am sure you knew!

I only use the motor to avoid landing out, and that very rarely. This
year, not at all other than self-launch.

--
Ian Strachan

Bentworth Hall West
Tel: +44 1420 564 195 Bentworth, Alton
Fax: +44 1420 563 140 Hampshire GU34 5LA, ENGLAND

JJ Sinclair wrote:

Eric wrote

Since I can't buy skill either, I bought a motor.



Now, Now, Eric we don't want to start that *motor* argument again, do we?
JJ Sinclair

That was a *contest* argument, I think!

And lest someone not understand the joking going on here, it's worth
noting that span, motors, and skill aren't mutually exclusive, as Klaus
Ohlmann and others flying in Argentina have shown them to be a potent
combination. Regardless of our individual skills, we all face the
challenge of finding that "sweet spot" combination of glider attributes
(performance, handling, cost, span, motor, competitiveness, etc.) that
will give us the most enjoyment for our money. The glider we end up with
affects the social aspects (who we fly with, when and where we fly), and
the social aspects also affect the glider we choose.
--
-----
change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

I don't see it on their web page..

BT

"Paul T" wrote in message
...
Here's the figures on the American DuckHawk (got to
be one of the most awful names for a sailplane) from
the promo sheet.

Windward Performance LLC takes its advanced technology
to the racing class.


Specifications
Empty Weight 300 LBS
Gross Weight 900 LBS
Wing Span 49.17 FT
Wing Area 74.93 FT^2
Aspect Ratio 32.2:1
Length 20.6 FT
Horizontal Span 6.8 FT
Vertical Height 4.5 FT

Structural Limits
+11.0 / -9.0 g's
Va, Vb = 165 KTS
Vne = 200 KTS

Performance
At 500 LBS, 6.7 Lbs/FT^2
Best Glide 50:1 at 50 KTS
Min Sink 94 FPM at 40 KTS
Stall Speed 35 KTS

At 900 LBS, 12.0 Lbs/FT^2
Best Glide 52:1 at 67 KTS
Min Sink 122 FPM at 57 KTS
Stall Speed 47 KTS
(data for 900 LBS, 12 PSF)

Airfoils
Inboard 12.7 % t/c
Outboard 10.2 % t/c


The DuckHawk has the broadest wing loading range available,
the highest maneuvering and redline speeds, and the
lowest inertias for snappy handling. The lower flying
mass within the 15m span constraint gives an induced
drag advantage of 49% at 500 LBS and 33% at 900 LBS
(span loading squared) compared to the competition


Time will tell - my money is on the Diana 2 which is
a development of the SZD-56-1 Diana. (Whose cockpit
is bigger than a Ventus a!). Incedently at Leszno they
were also talking about an 18m version and 22m Open
class version.

The info appears to be from a handout at the Sailplane Homebuilders
Association's Western Meeting at Tehachapi, CA, in September 2003. I
can't find my copy of the handout, and the website only mentions the
DuckHawk (Peregrine falcon, but maybe that name was taken, or more
likely, to match with the SparrowHawk now being produced).

BTIZ wrote:
I don't see it on their web page..

BT

"Paul T" wrote in message
...

Here's the figures on the American DuckHawk (got to
be one of the most awful names for a sailplane) from
the promo sheet.

Windward Performance LLC takes its advanced technology
to the racing class.


Specifications
Empty Weight 300 LBS
Gross Weight 900 LBS
Wing Span 49.17 FT
Wing Area 74.93 FT^2
Aspect Ratio 32.2:1
Length 20.6 FT
Horizontal Span 6.8 FT
Vertical Height 4.5 FT

Structural Limits
+11.0 / -9.0 g's
Va, Vb = 165 KTS
Vne = 200 KTS

Performance
At 500 LBS, 6.7 Lbs/FT^2
Best Glide 50:1 at 50 KTS
Min Sink 94 FPM at 40 KTS
Stall Speed 35 KTS

At 900 LBS, 12.0 Lbs/FT^2
Best Glide 52:1 at 67 KTS
Min Sink 122 FPM at 57 KTS
Stall Speed 47 KTS
(data for 900 LBS, 12 PSF)

Airfoils
Inboard 12.7 % t/c
Outboard 10.2 % t/c


The DuckHawk has the broadest wing loading range available,
the highest maneuvering and redline speeds, and the
lowest inertias for snappy handling. The lower flying
mass within the 15m span constraint gives an induced
drag advantage of 49% at 500 LBS and 33% at 900 LBS
(span loading squared) compared to the competition


Time will tell - my money is on the Diana 2 which is
a development of the SZD-56-1 Diana. (Whose cockpit
is bigger than a Ventus a!). Incedently at Leszno they
were also talking about an 18m version and 22m Open
class version.








--
-----
change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

Wil Schuemann achieved 50:1 with his modified ASW-12 (wings modified
and cut down to 15 m span). Very clear clean sink rate data on a very
good calm day with as little airmass movement as one could hope for.
This was in the early 80's with an aircraft that was old then.

Earlier, Greg Cole ) wrote:

...Very clear clean sink rate data
on a very good calm day with as
little airmass movement as one
could hope for.

I'd like to see that data. Is it available online?

Thanks, and best regards to all

Bob K.
http://www.hpaircraft.com