I have some experience with the benign spiral mode.
My previous sailplane was a Grob 104, Speed Astir.
The benign spiral mode was in the pilot's handbook.
It saved my bacon two times where clouds just reached
out and grabbed me. Very scarey when you can't see
anything and your inner ear is giving you all kinds
of bizare information. Very, very hard to keep my
hands and feet off of the controls.

My current sailplane is an LS8 and I can tell you that
the benign spiral mode does not exist. This aircraft
will overspeed and overbank no matter how it is trimmed
if you keep your hands and feet off of the controls.

My message is that you must practice this manuever
many times in various configurations with your particular
aircraft before you should even consider it as a possibility.

For those of you who do not understand how the Tru-trak
would allow you to recover from a death spiral, please
get some partial panel IFR training. The recovery
is the same in all aircraft I have trained in; level
the wings FIRST (this is what the Tru-trak will allow
you to do quickly) and then reduce the airspeed. If
you try to pull the nose up while in a bank you will
only increase the G loads very rapidly and put yourself
in an accelerated stall if you don't break the plane
first.

This is my two cents.

Guy Acheson, 'DDS'
At 16:48 08 November 2005, Raphael Warshaw wrote:
Todd:

Cindy and Marty at Caracole have demonstrated the benign
spiral to me in
both the K-21 and the Duo-Discus. It works in my LAK-17
(15m) at zero flap
with the trim 1/3 aft (wheel in or out) although, like
you, I've never tried
it from near redline or from a spiral dive. It needs
to be practiced, both
to see that it works in your airplane and, recurrently,
so that you really
do (hopefully) stay off the controls in an actual emergency.

Caracole routinely performs the benign spiral as a
training exercise, so
that their students and BFR candidates can experience
it. Perhaps either
Cindy or Marty could be enticed into joining this thread
as they know much
more about this and wave flying in general than I do
and have given
considerable thought to emergency procedures. They
provide serious mountain
wave training BTW, IMHO a VERY good idea before venturing
into the awesome
world of the wave.

Raphael Warshaw
1LK




'T o d d P a t t i s t' wrote in message
.. .
wrote:

Don't delude yourself by thinking that going IFC at
red line in the
Sierra Wave with just a turn and bank is anything like
a Microsoft
flight simulator with a partial panel or an instrument
flight in a
small plane with a partial panel and an instructor.

About once or twice a year, I find myself in the happy
situation of being at the end of a flight and having
10,000'
or more to kill off before landing. About 5 times
I have
used this altitude to try the benign spiral mode in
my
Ventus. Full trim back, full negative flaps, brakes
fully
open and hands and feet off the controls seems to
be
reasonably balanced. I've entered at speeds up to
90 knots,
and have always lost 8,000 or more before having to
take
control for landing. I've never seen excess G's, but
I've
never been in extreme wave conditions during these
tests and
I've never tried this by entering from extreme high
speeds
as one might be experiencing attempting to move out
from IMC
wave conditions. I have seen some 1/2- 1.5 g excursions,
but bank has always remained within 45 degrees.

I wonder if anyone else has tried this in a modern
glider
and wants to report their experience.
--
T o d d P a t t i s t - 'WH' Ventus C
(Remove DONTSPAMME from address to email reply.)