Puchacz fatal accident 18 Jan. 2004 at Husbands Bosworth.

I wonder about "letting go the stick" and letting the glider recover
itself - is this really being taught as a procedure?

I have not done this in glider but it works just great in a Super
Decathelon. Even a fully developed spin recovers quicky but you do add
opposite rudder. My acro instructor (placed 10th in the 2004 World
Advanced Aerobatic Championship in Sweden, FWIW) claims that most
reasonably stable aircraft will recover in this fashion. The ones that
don't are the Pitts's and Extra's - designed for acro and nothing else.
I intend to try it in an L23 when the season starts up again.

Tony V.

In article , Tony Verhulst
writes

I wonder about "letting go the stick" and letting the glider recover
itself - is this really being taught as a procedure?

This idea seems a good way to die if you are already in a full spin,
particularly at aft C of G. I do no deny that it may work in some
aircraft but to get the idea that it is a good standard technique could
cut your time short on this earth.

Of course, you may not be in a fully developed spin, just in the early
stages before full autorotation has developed. In that case, just
centralising the stick and rudder (perhaps easing the stick forward) and
levelling the wings with aileron may work, but that just shows that you
were not in a condition of full autorotation which is the "fully
developed spin".

The standard recovery procedure once a full spin has developed that
works for most aircraft is,

1. Full rudder opposite to the spin direction (make sure it really is
opposite to the rotation, I for one have applied the wrong rudder in a
spinning jet when I was caught by a surprise departure).

2. Short pause,

3. Stick centrally and progressively forward until the rotation stops.
Keeping on absolutely FULL opposite rudder is important, some people
have only applied partial rudder with disastrous effects such as getting
into a high rotation spin. "Centrally" on the stick is important too,
applied aileron can adversely affect spin recovery. Some aircraft I
have flown that were regularly used for spin training, had a white
circle painted on the middle of the instrument panel to mark the
"central aileron" stick position for use during spin recoveries.

4. Centralise the rudder when rotation can be seen to have almost
stopped (if you wait too late to centralise the rudder, you will spin
the other way).

5. Ease gently out of the resulting steep dive, taking care not to
apply too much G (too much G can lead to G-stall or flick, and make
things worse). Bear in mind that after rotation stops, some gliders are
nearly vertical or even beyond (pitch angle, say, 100 degrees where 90
degrees is vertically down).

I intend to try it in an L23 when the season starts up again.

I do not know the L23, but be very careful in experimenting with fully
developed spins in any aircraft, that is, those with the nose well down
and over about two full turns. They can catch you out unless you
approach the exercise systematically. Aft C of G is particularly
dangerous, as is not having enough height to bale out if things go wrong
.....

I do urge you to take such an exercise very seriously, as if your life
depended on it. As it does.

I speak as an ex military test pilot with much experience of stalling
and spinning in many types of aircraft, with and without engines. Any
fully developed spin is not to be taken lightly, at any altitude.

Recoveries from slow speed situations and wing-drops at the stall are
different, practise them often.

Conditions of full autorotation can be, often has been, and will
continue to be, fatal unless properly prepared for.

--
Ian Strachan

Ian Strachan wrote:

The standard recovery procedure once a full spin has developed that
works for most aircraft is,

It doesn't work in "most" aircraft, but rather in *all* aircraft which
are JAR certified. In fact, for an aircraft to get JAR certification,
this method must recover from a spin of at least five full rotations.
(If the CG is within the stated limits, of course!)

Stefan

On Fri, 14 Jan 2005 17:34:47 UTC, (Andreas Maurer)
wrote:

: Until now I have not even seen a Puchacz in real life - but the sheer
: number of spin accidents with experienced pilots suggests that
: something is wrong, don't you agree?

Not really. Spinnable gliders are going to be involved in more
spinning accidents than non-spinnable gliders. And I still think we
should consider all the solo spinners who die because they have been
trained - one way or another - to think that spinning is something you
have to do very deliberately. After all, that K21 wouldn't spin, so
this can't be a spin, so I'll just pull back more and

Ian


--

On 18 Jan 2005 10:16:04 GMT, "Ian Johnston"
wrote:


: Until now I have not even seen a Puchacz in real life - but the sheer
: number of spin accidents with experienced pilots suggests that
: something is wrong, don't you agree?

Not really. Spinnable gliders are going to be involved in more
spinning accidents than non-spinnable gliders.

You are correct, Ian - but here in Germany still a lot of Ka-7 and
ASK-13 are in use which do spin well and are commonly used for spin
training (not to mention other two-seaters that spin like the DG-500).
Yet I have not heard of a spin accident in one of them so far,
although their number far exceeds the number of Puchacz.



Bye
Andreas

At 16:00 14 January 2005, T O D D P A T T I S T wrote:
Andrew Warbrick
wrote:

I read it and came away thinking the Puch was still
a possible culprit.

How? As stated in the report the Puch spins readily
but recovers very easily. Quoted from the report:

'It can reasonably be concluded that the only control
mishandling of the PUCHACZ
that can lead to delay in spin exit is the retention
of full pro spin elevator…. '

I was referring to these parts of the report:

'The trial confirmed that the glider was compliant
with JAR
22; however, it considered that two areas
were worthy of additional comment. The trial considered
the
aircraft to be only marginally compliant in respect
of
stalls during turns and noted that avoidance of uncontrolled
rolling and spinning off a turn was reliant on pilot
awareness and skill. The trial also noted that height
loss
in a spin was significantly greater than on other types
and
that this was largely due to the steep attitude
(70 ° nose down) of the developed spin.'


The turning stall characteristics of the Puch would
seem to be irrelevant in this case since the accident
was apparently as a result of an intentional spin initiated
at an altitude where recovery should have been 100%
guaranteed by 800ft at the lowest.

And this part:
'The JAR recovery procedure first introduces full opposite
rudder to counter the yaw rate. This use of rudder
on the
Puchacz leads (to) a pitch down in the spin which reduces
incidence sufficient to facilitate auto recovery at
forward
CG where recovery then occurs. As the established spin
is
already estimated at 60-70 degrees, this pitch down
gives a
very steep exit, perceived to be over vertical but
probably
not so. It also contributes to the extensive height
loss
during exit. In a tense or panic situation, particularly
at
low level, the involuntary reaction could be expected
to be
retention of full aft stick. This will sustain a spin
against full opposite rudder at CG aft of 6.0 inches
aft
of datum.'

The CG of the accident aircraft was behind '6.0 inches
aft
of datum'


I really don't see where you're going, if you're saying
all gliders should recover from spins with the stick
held fully aft just using full opposite rudder, then
don't fly practically any single seater or any two
seater less docile than a K21.

I also noted the fact that including this accident
there
were six Puch spin accidents in the U.K. and five included
fatals. There are many more in the U.S.


The Puch seems to me to be the most common glider in
the UK for teaching all aspects of spin recognition
and recovery. So it's natural that, since many clubs
operate the Puchacz, some solely for spin training,
if a spin training related accident happens there's
a good chance it will be in a Puch. It's a question
of exposure, there are less spin training accidents
in other gliders because they fly less spin training
sorties.

I do, however, have to agree, we will never know exactly
what happened in this awful tragedy and any further
speculation over it is probably counter productive.

We agree it was an awful tragedy, but as I'm sure you
know,
there is concern over the number of fatal spin accidents
in
the Puch by relatively experienced pilots. A discussion
of
reports like this is how future tragedies are avoided.
I
was concerned by your comment that implied the report
exonerated the Puch, when I didn't read it that way.
At the
very least, I would think Puch operators would want
to make
sure they keep the CG of the Puch forward of the '6'
aft of
datum' point per the recommendation discussed in the
report, and adhere to the spin altitude limits.





I didn't make the original comment.

I am not sure if the Puch can be fully exonerated,
I have seen the video of a spinning Puch going flat
and eventually recovering, it gives me the heebie jeebies.
It wasn't mentioned in the report, but I understand
it happened at a very high density altitude, this accident
was at an airfield elevation of 500' on a cold winters
day.

However, I see nothing in the report to suggest that
the characteristics of the Puch were a contributory
factor. A phrase in the text you quoted was 'In a tense
or panic situation, particularly at low level, the
involuntary reaction could be expected to be retention
of full aft stick.' This is precisely why we do spin
recovery training, we're trying to create muscle memory
that if the world is going round but the G and airspeed
are not increasing you apply the full spin recovery,
you don't sit there with the stick on the back stop
trying to level the wings with the ailerons.

Actually, we try to put more emphasis on stall recognition,
if your involuntary response to a stall symptom is
to relax back pressure then you likely will not stall
or spin (this has saved me before in a high pressure
situation).

And yes, when flying the Puch I do try to keep the
CofG well forward of the aft limit and, as I said before,
I won't let a spin demo go beyond the incipient stage
below 1500', but then, I'm a wimp.

In article , Andrew Warbrick
writes

snip

I won't let a spin demo go beyond the incipient stage
below 1500', but then, I'm a wimp.

Dear Andrew,

You are not a wimp, you are sensible and alive. And so are your
students.

Having flown many spins in a military training environment, there was
always a "golden rule" on recovery heights. Heights for spin entry and
minimum heights for recovery were always such that if recovery had not
taken place, there was sufficient height to bale out or eject as
appropriate. I speak of the fully-developed spin, of course. Bale-out
heights were, to my recollection, something like 4000 ft for a Harvard
and Jet Provost and no less than 12000 ft for a Hunter. I recall a
Hunter spin bottom out once at 6000 ft but passing 12 it was recovering
so the crew stuck with it. They started at 35k, by the way!

It is this simple safety rule that some parts of the gliding world seem
to have forgotten. An instructional cult seems to have grown up in some
places that seems to think that low level spinning is an absolute
necessity to teach student pilots of the dangers. I instructed in
gliders for 35 years and IMHO, it is not necessary. Recovery from
fully-developed spins can be taught at a safe height just as in other
branches of aviation. There is nothing "macho" about spinning too low,
just a failure to understand the dynamics of the manoeuvre and the
possible dangers not only to the instructor but to the innocent student.

In any case, the emphasis in instruction should be on quick recovery at
the wing-drop or incipient stage before the spin has developed fully.
THAT should be practised very regularly and full multi-turn spins only
rarely to show what can happen if the correct actions are not taken
early enough.

I have even heard it said by some instructors that deliberate low level
spinning is required because the student must experience the visual
"ground rush" that he/she would get in a real situation of an
inadvertent spin at low level. This is a good way to an early grave,
particularly if something happens in one of these low level spins such
as control failure, rudder cable slackness, or even as simple as
someone's foot trapped the wrong side of a rudder pedal.

Also, spins are not regular reliable manoeuvres with streamlined stable
airflow, they are complex interactions between turbulent (stalled)
airflow, significant control moments and inertia/gyroscopic effects.
Occasionally, for no particular reason other than statistics, a spin
will go deeper into the stall (high alpha) than normal, and recovery
will be delayed. Think of this before continuing a deliberate
fully-developed spin below the height above the hard stuff at which it
would be possible to bale out if the recovery were to go wrong.

There are old pilots and there are bold pilots, but there are few old,
bold, pilots. An aviation truism, I think. Me, I'm old but still here
and enjoying cross country soaring!

--
Ian Strachan

Spot on Ian. The rules for the Air Cadets in the UK,
RAF rules, prohibit intentional spinning below 2500ft
in a glider. If you are still spinning you abandon
at this height and to my mind this is one of the most
sensible rules the AC have. Even that might be cutting
it a bit fine depending on how easy it is to actually
get out of the glider.


At 20:00 14 January 2005, Ian Strachan wrote:
In article , Andrew Warbrick
writes

snip

I won't let a spin demo go beyond the incipient stage
below 1500', but then, I'm a wimp.

Dear Andrew,

You are not a wimp, you are sensible and alive. And
so are your
students.

Having flown many spins in a military training environment,
there was
always a 'golden rule' on recovery heights. Heights
for spin entry and
minimum heights for recovery were always such that
if recovery had not
taken place, there was sufficient height to bale out
or eject as
appropriate. I speak of the fully-developed spin, of
course. Bale-out
heights were, to my recollection, something like 4000
ft for a Harvard
and Jet Provost and no less than 12000 ft for a Hunter.
I recall a
Hunter spin bottom out once at 6000 ft but passing
12 it was recovering
so the crew stuck with it. They started at 35k, by
the way!

It is this simple safety rule that some parts of the
gliding world seem
to have forgotten. An instructional cult seems to
have grown up in some
places that seems to think that low level spinning
is an absolute
necessity to teach student pilots of the dangers.
I instructed in
gliders for 35 years and IMHO, it is not necessary.
Recovery from
fully-developed spins can be taught at a safe height
just as in other
branches of aviation. There is nothing 'macho' about
spinning too low,
just a failure to understand the dynamics of the manoeuvre
and the
possible dangers not only to the instructor but to
the innocent student.

In any case, the emphasis in instruction should be
on quick recovery at
the wing-drop or incipient stage before the spin has
developed fully.
THAT should be practised very regularly and full multi-turn
spins only
rarely to show what can happen if the correct actions
are not taken
early enough.

I have even heard it said by some instructors that
deliberate low level
spinning is required because the student must experience
the visual
'ground rush' that he/she would get in a real situation
of an
inadvertent spin at low level. This is a good way
to an early grave,
particularly if something happens in one of these low
level spins such
as control failure, rudder cable slackness, or even
as simple as
someone's foot trapped the wrong side of a rudder pedal.

Also, spins are not regular reliable manoeuvres with
streamlined stable
airflow, they are complex interactions between turbulent
(stalled)
airflow, significant control moments and inertia/gyroscopic
effects.
Occasionally, for no particular reason other than statistics,
a spin
will go deeper into the stall (high alpha) than normal,
and recovery
will be delayed. Think of this before continuing a
deliberate
fully-developed spin below the height above the hard
stuff at which it
would be possible to bale out if the recovery were
to go wrong.

There are old pilots and there are bold pilots, but
there are few old,
bold, pilots. An aviation truism, I think. Me, I'm
old but still here
and enjoying cross country soaring!

--
Ian Strachan

I think that the strong criticism of the Puch is totally unwarranted.
Puchacz was designed as a initial training ship but also one which can
fly many more aerobatic maneuvers then some other gliders. Puch can fly
rolls, loops, spins, hammerheads, snaps, you can teach inverted flight
in it, etc. It is called "advanced aerobatic trainer". It is quite a
remarkable glider. Of course the Germans will never admit it, so they
going to insist on their DG's. The point here is, after reading the
accident report it indicates to me a pilot error. Each glider has a
different characteristics. Some of them will recover with the stick in
the full aft position and some will not. Plain and simple. Each glider
comes from the factory with its manual. And that manual will tell you
how to fly specific ship. This is the same as comparing 7ECA Citabria,
which will recover from a spin with full aft elevator, to a Sukhoi 26:
this one needs to be recovered with the stick forward to break the
stall. You see, pilots flying aerobatics are aware of the handling
characteristics of the planes they fly. If I will be teaching a student
spins, I will be at 5000 + AGL. Why? Because if something goes to crap
I still have time to get out. They were flying spins at 1500. So, you
might say it is legal because the FARs are saying "no aerobatic
maneuvers below 1500' " . But is this really smart? Anyway, we can beat
the horse to death and everybody will have a different opinions. I
flown in SZD-50-3 Puchacz in the early and mid eighties with test pilot
January Roman with saddle bags filled with led near its tail to
simulate the aft C.G. without any problems. In addition we have done
those spins inverted as well...no problems. And we have done several
times. Puchacz is a trainer but it is also more then a trainer.
Approach it properly, with good manners and everything will be fine,
screw with it and it will bite. But the same is true for other gliders
and airplanes. Even for the DG. Everything else is in the pilot hands.

On Fri, 14 Jan 2005 19:41:29 UTC, Don Johnstone
wrote:

: Spot on Ian. The rules for the Air Cadets in the UK,
: RAF rules, prohibit intentional spinning below 2500ft
: in a glider. If you are still spinning you abandon
: at this height

How many gliders will not recover from a spin with 2,500' to spare?
What are the injury rates for parachute jumps from gliders?

Ian
--