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Old January 19th 05, 05:53 PM
Don Johnstone
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Interesting........how is the information in the POH
obtained, yes the answer is test flying. But what is
tested? There are requirements laid down that gliders
must conform to in spin recovery. There are two ways
of approaching testing.
1. Test to see if the glider complies with the requirements
during the test flights. If it does it has passed.
2. Fly in all possible configuarations and allowable
C of G positions and see how the glider behaves. Fly
in configurations which are most unlikely to be met
in normal service and with the C of G right on the
theoretical limits and maybe beyond and assess the
behaviour.
Which approach do you think a glider manufacturer test
pilot takes. Prove that the glider complies with the
requirements or test right to the limits. The latter
is the way that military aircraft are tested at great
expense, do you honestly think that glider manufacturers
can go to that expense.
It has been said that the Puch has featured in several
fatal spin ins. What was the cause? In the absence
of any mechanical failure it is assumed that the failure
to recover was caused by pilot mishandling, and that
may be the case. We can never know that, the only person
who could prove or disprove that is very difficult
to communicate with unless you happen to know a medium.

We do not KNOW that there is not a configuration or
combination of configuration and airframe loading which
will make a spin recovery impossible or more difficult
and until someone survives such an occurrence we will
not KNOW. We do know that no-one has found such a configuration
and survived to tell anyone about it, which is not
the same as saying it has never or cannot happen.
You may think that my scenario is unlikely, I freely
admit that I do but I do not intend to find out the
hard way. Spinning below safe abandonment height leaves
no option if it all goes to rats.

What is a safe abandonment height, that is another
question. I know what I think mine is. Do you know
what yours is? I pray that I never have to find out
if I am right.

Make love to the wife.........do people still do that?
:-)

At 16:31 19 January 2005, Stefan wrote:
Don Johnstone wrote:

I too know how to recover from a spin, and I don't
need to find an instructor, I were one.


Then I'm even more puzzled that you consider exploring
spins in a
certified glider, which's spin recovery procedures
are described in
detail in the POH, as test piloting. I always thought
test piloting was
about exploring things which are not described in the
POH. But then, I'm
not an instructor.

The points Ian was making was why try something that
had no useful purpose


I surely hope you don't ever make love to your wife
whithout producing
children, because this would not have any useful purpose.

Stefan