Spins, Spiral Dives and Training

On 3 July, 18:20, "Paul Remde" wrote:

I have spun our club's Junior and have never seen those different cycles.
However, I weigh about 190 Lbs plus parachute. *I'm sure the spin
characteristics are very different at different weights.

You are quite right - I should have said that the oscillation is at
lighter weights / after CoGs.

*I thought the
Junior spun aggressively, but I found it easy to exit the spin immediately
after multiple (I don't recall how many - maybe 3 or 4) rotations. *I love
spinning gliders!

Do you have Polish blood, by any chance?

Ian

Don,

What height I am prepared to deliberate spin from when instructing very
much depends on the type of glider I am flying. K13s as low as 800ft,
Puchaczs (is the plural Puchi?) Grob 103s and DG1000s probably not below
2000ft.

I don't see why spinning exercises are only 'addressing the needs of the
instructor'. I would personally prefer not to be tumbling out of the sky,
but pupils have to be taught that such things can happen, and how to
recover from them. After every spin entry situation, I also demonstrate or
talk them through how to avoid these situations, as do most other
instructors trained or retrained in the last twenty years, so I don't
agree with your premise that spin avoidance is not taught.

Low level spins are easily avoidable by flying a bit faster and flying
accurately, even in a Puch. If you spin off a final turn, it's game over,
and just a case of whether you get killed or just seriously injured! You
might just save yourself if you recognise the incipient stage in time and
get the stick forward.

Derek Copeland


At 14:45 03 July 2009, Don Johnstone wrote:


snip
There is no debate, more people are killed in deliberately induced spins
than in accidental ones and yet people still deliberately spin at
ridiculously low altitudes, and by that I mean below 2500ft.

This despite the fact that knowing the spin recovery procedure would be
unlikely to help in the most common spin, that off the final turn. The
only thing that would help there is spotting the impending spin before
it
happened but little or no emphasis is placed on this in current
training.
We have the situation where the most life threatening situation is not
addressed by proper training and an aspect, which gives an instructor
the
opportunity to scare his pupil witless, is very well covered.
Current spin training is more about addressing the needs of the
instructors than about addressing the need of their pupils. I would
suggest that not commencing spin recovery procedure in a low spin, as
off
the final turn, would be more likely to save your life than getting part
way through the recovery.

More emphasis is needed on recognition of the lead up and prevention, if
that was done properly then we might improve things. By all means teach
it
but rather than checking recovery every year check the ability to
recognise
and prevent. Less risk and the potential of greater benefit, it would
also
reduce the need for clubs to own the potentially lethal Putchaz as the
recognition and prevention could be done in any two seater.

I heard of one being test-flown by a gentleman who was certainly not too
light. Apparently it recovered on it's own and he only had to pull out
of the dive...

In message , Paul Remde
writes
Hi Ian,

I have spun our club's Junior and have never seen those different
cycles. However, I weigh about 190 Lbs plus parachute. I'm sure the
spin characteristics are very different at different weights. I
thought the Junior spun aggressively, but I found it easy to exit the
spin immediately after multiple (I don't recall how many - maybe 3 or
4) rotations. I love spinning gliders!

Best Regards,

Paul Remde

"Ian" wrote in message
...
On 3 July, 12:38, Surfer! wrote:

BTW have seen folks allowed to fly the K21 solo without spin training,
but *not* the Juniors.

Juniors have a complicated spin mode which is generally three turns
nose down and recoverable, three flat and unrecoverable, rinse,
repeat. If you don't recover in the first three turns (Turn 1: ****,
better get the nose up. Turn 2: why didn't that work? Turn 3: What's
spin recovery again?) you just have to sweat it out for a few hundred
feet or your current altitude, whichever is less.

Ian


--
Surfer!
Email to: ramwater at uk2 dot net

Ian


In one message you said:

"Juniors have a complicated spin mode which is generally three turns
nose down and recoverable, three flat and unrecoverable, rinse,
repeat. If you don't recover in the first three turns (Turn 1: ****,
better get the nose up. Turn 2: why didn't that work? Turn 3: What's
spin recovery again?) you just have to sweat it out for a few hundred
feet or your current altitude, whichever is less."

and elsewhere

"You are quite right - I should have said that the oscillation is at
lighter weights / after CoGs."

So a Junior behaves strangely with an aft CofG, and in your words is
unrecoverable.
My first point is the glider should not be flying and should certainly
never have been certified under JAR if that is true, unless of course the
CofG is aft of the permitted limit.

What is really interesting is what you say about the Puchaz, which comes
from the same design shop and that is:

"That is a correlation, not a causation. Most Puchacz spin accidents
occur with instructors on board: perhaps the problem lies with
instructor training?"

In fact I cannot recall an accident where a Puchacz has spun in solo. You
are absolutely correct then when you say the accidents only occur with an
instructor on board, or more correctly when the back seat is occupied. So
we have a different loading situation in a glider which comes from the
same design shop as another glider with known spin recovery problems if
the CofG is moved aft. So is there the same problem with the Puchacz as
with the Junior, and is that problem in fact worse to the extent that
there is no recovery? We cannot know for sure but there is evidence that
points that way.

Does this not raise any concerns? I know we cannot prove that the Puchacz
will not recover under certain loading conditions any more that we can
prove that the spin ins have been caused by pilot error. The truth is that
the Puchacz has been proved to be a glider that frequently kills people. I
experienced a spin recovery in a Puchacz that was prolonged to an extent
that I thought it was not going to recover. It did eventually. It is very
easy to blame the unknown on pilot error but I suggest that we should at
least consider the possibility that there is a major problem with the
Puchacz, one which should mean that it is not intentionally spun as an
absolute minimum. We are never going to have a pilot tell us "This glider
was impossible to get out of a spin", because if that is the case he is
dead and not saying much.

My personal view is that there is sufficient evidence to show that the
Puchacz is a dangerous glider, so dangerous in fact that it should never
be flown again.

Don Johnstone wrote:

with the Junior, and is that problem in fact worse to the extent that
there is no recovery? We cannot know for sure but there is evidence that
points that way.

Yes, we can and do know. The Puchacz as well as the Junior have been
frequently flown in aerobatics contests. To my knowledge, no Puch nor
Junior has been spun into the ground during a contest. So they do
recover. More, they even do recover forseeably and precisely, otherwise
they wouldn't be flown in contests.

My personal view is that there is sufficient evidence to show that the
Puchacz is a dangerous glider, so dangerous in fact that it should never
be flown again.

Detailed 'puchy' spin analysis found he

http://www.ssa.org/members/johnson/f...72-1994-06.pdf

It's actually pronounced poo-hots BTW, but I'm not sure how it
translates in plurality... regardless, it is odd how many have drilled
into the ground with competent pilots and instructors onboard though.
Of course there's the rudder pedal theory (rear pilot's feet
obstructing mechanism's full travel...), but it's just that- a theory.

-Paul

At 21:31 03 July 2009, John Smith wrote:
Don Johnstone wrote:

with the Junior, and is that problem in fact worse to the extent that
there is no recovery? We cannot know for sure but there is evidence
that
points that way.

Yes, we can and do know. The Puchacz as well as the Junior have been
frequently flown in aerobatics contests. To my knowledge, no Puch nor
Junior has been spun into the ground during a contest. So they do
recover. More, they even do recover forseeably and precisely, otherwise
they wouldn't be flown in contests.


Yes, but are they flown in contests with the CofG aft and in the case of
the Puchacz with the rear seat occupied with a heavier pilot? I doubt it.
I am not saying that under all loading conditions that there is a
problem. What I am suggesting is that under some loading conditions there
may well be. What has been said in previous posts tends to indicate there
might be.
Evidence from pilots who recover is unhelpful, evidence from pilots who
don't is not available.
My one experience (in a Puchacz) showed me that there was a problem and I
resolved from that day that I would never walk under one let alone fly in
one again. I assume the instructor filed a report, at the time I was not
involved with the BGA at all.

At 21:50 03 July 2009, sisu1a wrote:

My personal view is that there is sufficient evidence to show that the
Puchacz is a dangerous glider, so dangerous in fact that it should
never
be flown again.

Detailed 'puchy' spin analysis found he

http://www.ssa.org/members/johnson/f...72-1994-06.pdf

It's actually pronounced poo-hots BTW, but I'm not sure how it
translates in plurality... regardless, it is odd how many have drilled
into the ground with competent pilots and instructors onboard though.
Of course there's the rudder pedal theory (rear pilot's feet
obstructing mechanism's full travel...), but it's just that- a theory.

-Paul

The above document is only available to SSA members, it might be of some
use to the wider gliding community

On Jul 3, 4:31*pm, John Smith wrote:
Don Johnstone wrote:
with the Junior, and is that problem in fact worse to the extent that
there is no recovery? We cannot know for sure but there is evidence that
points that way.

Yes, we can and do know. The Puchacz as well as the Junior have been
frequently flown in aerobatics contests. To my knowledge, no Puch nor
Junior has been spun into the ground during a contest. So they do
recover. More, they even do recover forseeably and precisely, otherwise
they wouldn't be flown in contests.

I can cite more than one instance where an "experienced pilot" has
spun
a "well known" design, under "normal" circumstances resulting in
"unexpected"
characteristics. There are dozens, or more, variables involved and
to assume that you have seen all the possibilities is shortsighted to
say the
least. You should not assume that you are doing everything the same
way every
time, with identical equipment. I've experienced such episodes and no
longer
will "explore" that part of a flight envelope. An appropriate phrase
for such
activity is "practice bleeding".

Detailed 'puchy' spin analysis found he

http://www.ssa.org/members/johnson/f...72-1994-06.pdf

The above document is only available to SSA members, it might be of some
use to the wider gliding community

Sorry bout that... I can't figure out how to publicly post it yet, but
I can email anyone that PM's me a copy of it if they like...

-paul at eaglebrandproducts dot com