Puchacz fatal accident 18 Jan. 2004 at Husbands Bosworth.

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.