ASW 20 SPIN CHARACTERISTICS

Very thoughtful of Andreas to put this together. Based on 17+ years
and 2000 hours in a 20, I would add only the following thoughts...

You may move the flap handle from position 2 to position 4 on take off
as soon as the pass the start point of the tow plane. This is where
wings typically drop, in the wake turbulence as you enter it at low
speed. Once past it, you will find plenty of control authority. I
prefer flap position 4 since it lowers the nose, allowing a much
improved view of the tow rope.

When thermalling, use flap position 4, or drill a hole between
positions 3 and 4 if you want less drag. If you need to shift your
circle or correct for gusts, move the flap handle to 3 as you make
aileron inputs. This will give you a better roll rate. As soon as you
have established the desired angle of bank, pop the handle back into
positive (3.5 or 4).


Martin Gregorie wrote in message . ..
On 4 Jul 2004 17:54:39 -0700, (Ventus B) wrote:

I have been considering buying an ASW20, ASW20B, or ASW20C. I knew
they were champions in their day and still have a lot of admirers.
However a few folks from my club say they have some nasty spin
characteristics. Specifically, that they have a tendancy to not only
immediately spin when stalled, but will go inverted as they spin. Can
anyone eloborate or corroborate? I normally only hear good things
about the 20.
Respectfully,

Assuming you haven't seen the handbook yet, the following may answer
some of your questions:

http://www.gregorie.org/gliding/asw2..._handling.html

It was written by Andreas Maurer for a pilot who was converting from a
Pegasus: in fact the guy I bought my '20 from. I've found it very
useful, especially as I, too, was converting from a Pegasus. IMO it
tells you most of what you need to know about the '20 that isn't in
the flight manual.

Chris OCallaghan wrote:
....
When thermalling, use flap position 4, or drill a hole between
positions 3 and 4 if you want less drag.

Thank you, Chris. My 20B had a 3.5 hole drilled when we bought it but I
had no advice on its purpose or use. I was puzzled when I couldn't
relate the Flight Manual descriptions to what my glider had. Eventually
I worked it out.

I would be interested in any advice anyone can give on the use of 3.5.
I tend to use it for nearly all thermalling and only use 4 for landing.
Am I right? Is a 3.5 hole common? Did Schleicher's get it wrong?

GC

On Sat, 17 Jul 2004 00:36:28 +1000, Graeme Cant
wrote:


Thank you, Chris. My 20B had a 3.5 hole drilled when we bought it but I
had no advice on its purpose or use. I was puzzled when I couldn't
relate the Flight Manual descriptions to what my glider had. Eventually
I worked it out.

I would be interested in any advice anyone can give on the use of 3.5.
I tend to use it for nearly all thermalling and only use 4 for landing.
Am I right? Is a 3.5 hole common? Did Schleicher's get it wrong?

It depends what you use 4 for: For thermalling at normal bank angles
(20-30 degrees) 3 is the better setting (the 20 converst excessive
speed into height a lot better in 3 than in 4), but very tight turns
combined with high wing loading (or forward CG) need 4.

Many 20 owners drilled the 3.5 hole, but I have to admit that I tested
this setting and I never felt 3.5 to be an advantage over 3 (I hold
the flap handle at 3.5 before I decided not to drill a hole there). At
3 the nose is significantly higher than in 3.5, but I think the 20's
airfoil loves high AoA's. If the AoA of the 20 is too low (in other
words: Flap setting too positive for current airspeed/g-load
combination), the drag rise is drastic - very easy to feel the
deceleration.

One more thing why I love the 20: The flap handle tells you which
position it wants to be in - it moves itself into the optimum position
(if you help it overcome the friction with your hand).

Bye
Andreas