Mark Grubb wrote:
CV wrote in message ...

Andreas Maurer wrote:

......it's going to
take a runway of *at least* 6.000 ft and a sideslip to *very* low
altitude to be able to land without using the airbrakes.


While it seems a excessive for a private rating, most pilots can train
to safely and repeatedly conduct this maneuver in considerably less
airport than 6000 ft.! I have done it a lot and some of my friends
could do it consistently. Success requires a very high degree of
speed discipline - even in extremely "slipped" attiudes, a very good
understanding of slips and adverse yaw, and a different mindset
regarding pattern altitudes and shapes. One also must slip to very,
very low altitudes - e.g., through the flair. Sounds bad but it is
not really that bad.

Remember that AS-W12 pilots routinely (1000's of flights) slipped a
50:1 glider to a landing in considerably less than this in extreme
conditions including Appalachian ridge days(Schuemann), wild thermal
days in TX (Scott, Greene) and monster wave days in NV (Herold).

I have landed 100's of flights in glass in Tehachapi, CA without drag
devices. These landings were typically over a 30 ft obstacle at
density altitudes 5000 ft, and ALL stopped in less than 2500 feet.
More than 50 if those were in an AS-W12. Other gliders involved:
AS-K21, AS-W20, AS-W17, G-103, G-102, LS-4, and Caproni (not
recommended!).
I must take issue with that Mark. I am a much less experienced pilot than you,
but let's look at this from my perspective. As safety officer at my club I would
exercise my prerogative of referring anyone who wanted to perform slips into
the flare for any reason to the CFI for review of their permission to fly.

A few comments -
1] I know it can be done, and even reasonably safely.
2] I know it is dangerous to do this in anything with long wings, and we have a
sloped undulating runway with long grass near the runway.
3] Given the remote probability of ever experiencing this I think the standard
way of testing here, is better. Student gets to find airbrakes frozen at some
point in the circuit, and needs to demonstrate decision making, and execution.
(but the landing is carried out normally)
4] Show that you can perform slips, and S-turns and low approaches by all means.
5] Decision making is far more important than demonstrating a dangerous manouever.
6] Experience is less indicative of safety than is attitude, ask someone like JJ
where most of the repair jobs come from.

For what it is worth - My glass experience is restricted to the Std Cirrus and
Grob 103 Twin II. The Cirrus slips if you want her to, but turbulence over the
tail and pitch sensitivity make low slips highly undesirable. The Grob is heavy
and predictable, but roll rate is not exactly electrifying at low speed. In both
cases the extra speed you would be carrying for control would negate any
advantage. Since it does not benefit you, I can't see any justification for
doing something dangerous.

Our club's founder - Dieter Henschell learned to fly in the 1940s. His favorite
demonstration to pupils who insisted on too high approaches was to make a normal
approach in the Blanik and then proceed up the 2km runway with the brakes closed
from around 10m height and 100km/h. All the way reciting in his gentle German
accent, look the speed is X and I am still flying.. Look the speed is now x-5
and I am still flying...
Most students got the point in one. And that was with a Blanik. Tried something
similar with my Cirrus - the only way to get her stopped on tar without brakes
is to be dangerously slow over the numbers 2m up and 80km/h. That is 10kt
above stall. Eventually touched down tail first - a gentle full stall landing
indicating around 60km/h nearly 400 m later. Work it out, effective L/D is
probably around 70, and I have to lose 15-20km/h - that is a fair amount of
energy. My wingtip on the ground has less than one metre clearance, from a 2m
height I only have 3m clearance, over a length of 7.5m - do the trigonometry
that is a serious cartwheel type impact at a slip angle of less than 21 degrees.
The Cirrus does not seem to lose much in a slip of less than 30 or so degrees -
then there is the fence at 1.2m to consider - what am I achieving, other than to
demonstrate my poor judgment by practicing slips into the flare?

Just because it was standard procedure some years ago, with a glider that had
design faults with inadequate drag controls does not mean it should still be
standard practice. The discussion about spin demonstration in the circuit is an
example. Eventually the BGA dropped this after a number of fatal accidents. Why
do people have to die demonstrating something that is marginally useful, and has
so low probability of happening, relative to the probability of injury
demonstrating it?

Imagine a fighter pilot having to demonstrate a successful ejection at each
flight review. Same question, why on earth would you expect that?