PCC Presentation

The same observation can be done when standing near the cocpit.

No it can't.

My spouse wouldn't even reach the rudder pedals.

I don't think it's necessary to check the rudder pedals on POH. I can check it
myself when in the cockpit just by the mass of the feel.

I would like to hear arguments against doing a PCC the simple way - PIC
standing outside the cockpit moving stick and rudder and observing the
controls while the assistant is holding the control surfaces.
Again, the simpler it is the more likely it will be done.

And that is EXACTLY how the standard cirrus was checked, and the pilot died.
Frankly, IMO, it's simpler to have the assistant outside the cockpit (I never
said have the assistant in the cockpit) moving the stick away and towards me.

Jim Vincent
CFIG
N483SZ
illspam

(DG's) have an elevator pushrod that
terminates in a 'C' shaped fitting. A roller bearing on the elevator fits
snugly into the open 'C', a reliable automatic hookup but does need
attention at assembly time.

Wrong there, my friend. The standard Cirrus accident where the elevator
disconnected failed because the pushrod did not catch in the "C". Admittingly,
it is very difficult to make it happen, but it can and did. Had he done a
proper inspection, he would have caught it. This is proven by tests Tom Knauff
did on a standard Cirrus. After much effort, he was able to invoke the failure
mode.



Jim Vincent
CFIG
N483SZ
illspam

Jim Vincent wrote:
(DG's) have an elevator pushrod that
terminates in a 'C' shaped fitting. A roller bearing on the elevator fits
snugly into the open 'C', a reliable automatic hookup but does need
attention at assembly time.


Wrong there, my friend. The standard Cirrus accident where the elevator
disconnected failed because the pushrod did not catch in the "C". Admittingly,
it is very difficult to make it happen, but it can and did. Had he done a
proper inspection, he would have caught it. This is proven by tests Tom Knauff
did on a standard Cirrus. After much effort, he was able to invoke the failure
mode.

After the glider is assembled, and before the pilot does the PCC,
doesn't he walk around the glider and inspect the control surfaces and
move them through their full deflections, in addition to other
inspections? Isn't the improperly assembled elevator noticable during
this inspection?

When the Std Cirrus elevator is connected improperly in this fashion,
isn't the front of the elevator quite high and easily visible to pilot
standing near the cockpit while doing the PCC?

It's been a long time since I've had my Std Cirrus, but I think a pilot
that does a proper inspection has as least 3 chances (including looking
in the little window right after assembly) to notice an improperly
assembled elevator without the need to be at the control surfaces during
the PCC.

I'm with Ramy on this one: keep it simple. This one unfortunate case is
not a good argument for everyone to have the pilot at the control
surfaces during the PCC.

--
-----
change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

"Jim Vincent" wrote in message
...
(DG's) have an elevator pushrod that
terminates in a 'C' shaped fitting. A roller bearing on the elevator fits
snugly into the open 'C', a reliable automatic hookup but does need
attention at assembly time.

Wrong there, my friend. The standard Cirrus accident where the elevator
disconnected failed because the pushrod did not catch in the "C".
Admittingly,
it is very difficult to make it happen, but it can and did. Had he done a
proper inspection, he would have caught it. This is proven by tests Tom
Knauff
did on a standard Cirrus. After much effort, he was able to invoke the
failure
mode.


Sorry Jim but where was I wrong? It is reliable - provided that the
assembler pays attention to what they are doing as I said. If it is
assembled correctly it is extremely unlikely to fail unless a pushrod
corrodes, a belcrank fails, a mounting delaminates or other completely
unrelated failure occurs. I first typed 'fairly reliable connection' in my
post but changed it to 'reliable' on reflection with the caveat that it does
need attention to detail. BTW I didn't know the Cirrus used this type of
hookup. My post was not meant to be an exhaustive description of how
automatic hookups work just a fairly reasonable response to Miguels'
question.

Ian

After the glider is assembled, and before the pilot does the PCC,
doesn't he walk around the glider and inspect the control surfaces and
move them through their full deflections, in addition to other
inspections? Isn't the improperly assembled elevator noticable during
this inspection?


Apparently not. A Twin DG at out club has a small storyboard attached to the
top of the fin leaving no doubt in the riggers mind exactly how , where and
when to put things when rigging. I helped with the stab assembly once and
when it didn't go together easily. I suggested the pilot read the list on
the tail, we removed and refitted the stab discovering in the process that
it had gone together wrong first time round! Everything worked OK but the
travels were all out of kilter.

Ian

Miguel Lavalle wrote in message ...
Jim,

My Jantar Std 3 doesn't have automatic connectors for
the ailerons and elevator. Does anybody know wheter
this conecctions are of the L'Hotellier type?

Regards

Miguel Lavalle
N5SZ


The original Jantar STD had manual hookups but they were not
L'Hotellier type.
Those connection were pin in one component mating with a hole in the
other component and secured by a sleeve that slid over both. The
sleeve ensures the fitting is correctly mated and no additional safety
is required. (That's based on memory from over 15 years ago). I have
no experience with the -2 or -3 but would be surprised if they changed
to L'Hotellier which are a ball which mates with a cup. After mating
the 2 components, the cup is closed with a plunger driven by a spring
loaded wedge.

If one of these descriptions matches your glider then you have your
answer.


Andy

Hi,

According to http://www.standardcirrus.org/, Knauff did not find it
difficult to get the stabilizer hooked up improperly, nor did the
NTSB. I discussed this with the NTSB investigator. Unless one knows
what Tom describes in the link, and instructs the assistant, things
can happen. There is also a sight glass installed on the top.

Unfortunately, I had the experience of watching the accident occur and
the aftermath. The individual who did the check was NOT instructed on
anything other than to observe movement. I spoke with one experienced
glider pilot who had owned a std. cirrus and never heard of the
potential problem.

The point is, know your manual and any quirks associated with the
glider, instruct your helper in the proper PCC procedure and have
someone double check your critical assembly. And, I sure hope no one
ever takes off having automatic hookups and not performing any of the
checks. Trust nothing to chance.

NTSB Identification: NYC02FA159. The docket is stored on NTSB
microfiche number DMS.
14 CFR Part 91: General Aviation
Accident occurred Saturday, August 10, 2002 in Hilltown, PA
Probable Cause Approval Date: 12/30/03
Aircraft: Schempp-Hirth Standard Cirrus, registration: N47SS
Injuries: 1 Fatal.
The glider was being towed by an airplane for takeoff, when it was
observed to bounce hard on the runway twice, then it assumed a steep
nose up attitude. The tow rope broke, and the glider impacted the
ground in a near vertical descent. The C-hook on the stabilator push
rod, was found in front of, and not connected to the roller bearing on
the stabilator. The pilot's flight experience was over 3,000 hours
with about 84 hours in gliders. He had accumulated 28 hours in the
accident glider, including 17 flights. This was the first glider the
pilot had operated, that he was required to disassemble for storage
and reassemble for flight. Witnesses reported the pilot experienced
difficulty with the assembly process. A view window was located on top
of the stabilator to check for proper engagement of the C-hook, and
the AFTER ASSEMBLY checklist called for it to be used to check for
proper assembly. A witness reported the pilot moved the control stick
in the cockpit and observed movement of the flight controls, but he
was not observed to actually check the view window for proper
assembly. A check of another glider of the same make and model found
it was possible to lock the stabilator in place on top of the vertical
stabilizer, with the C-hook in the same place as found on the accident
glider. In this configuration, the control rod that held the C-hook
was pressed against the roller bearing and held in place by friction.
However, the incorrect assembly was visible through the view window on
top of the stabilator, and when the stabilator was held in place, it
was still possible to move the cockpit control stick abut 1 inch
forward or aft, with no corresponding movement on the stabilator.

The National Transportation Safety Board determines the probable
cause(s) of this accident as follows:

The pilot's improper pre-flight, and failure to follow procedures in
the flight manual to determine that the stabilator was properly
connected prior to flight, and which resulted in a loss of control
while under tow, and uncontrolled impact with the ground.


Chip F.

A witness reported the pilot moved the control stick
in the cockpit and observed movement of the flight controls, but he

I had the opportunity to discuss this in detail with Tom Knauff and the owner
of the Cirrus on which the replicated the failure mode.

The flight control would move correspondingly with the stick movement because
the weight of the elevator kept the C-hook and the elevator in contact. IF
either one of the team (PIC at cockpit or assistant at control surface) had
done a proper PCC, it would have been evident either while applying resisting
pressure while moving the stick in full deflection or from doing a jiggle test.

The assistant in this case is a licensed glider pilot.

I was the field manager that day, and hope never to experience something like
this again. To this day, I still see most people there doing a simple prayer
hand PCC. Go figure.

Jim Vincent
CFIG
N483SZ
illspam

Eric Greenwell wrote in message ...
Jim Vincent wrote:
(DG's) have an elevator pushrod that
terminates in a 'C' shaped fitting. A roller bearing on the elevator fits
snugly into the open 'C', a reliable automatic hookup but does need
attention at assembly time.


Wrong there, my friend. The standard Cirrus accident where the elevator
disconnected failed because the pushrod did not catch in the "C". Admittingly,
it is very difficult to make it happen, but it can and did. Had he done a
proper inspection, he would have caught it. This is proven by tests Tom Knauff
did on a standard Cirrus. After much effort, he was able to invoke the failure
mode.

After the glider is assembled, and before the pilot does the PCC,
doesn't he walk around the glider and inspect the control surfaces and
move them through their full deflections, in addition to other
inspections? Isn't the improperly assembled elevator noticable during
this inspection?


Eric,

I did misassemble my Std. Cirrus tailplane once. Just once.
The person that showed me how to assemble didn't know that it could go
together wrong. I guess I didn't either, until I did it.

When the Std Cirrus elevator is connected improperly in this fashion,
isn't the front of the elevator quite high and easily visible to pilot
standing near the cockpit while doing the PCC?


Not if the pilot is sitting in the ship!! And the trim is all the way
forward to ease assembly, so the tailplane is normally high at this
point anyway.

It's been a long time since I've had my Std Cirrus, but I think a pilot
that does a proper inspection has as least 3 chances (including looking
in the little window right after assembly) to notice an improperly
assembled elevator without the need to be at the control surfaces during
the PCC.

The window gets dirty easily and is not very big. It should be cleaned
every year (at least) at annual time. Even then, the plastic yellows,
and it is dark in there

I'm with Ramy on this one: keep it simple. This one unfortunate case is
not a good argument for everyone to have the pilot at the control
surfaces during the PCC.

My misassembly was caught at the PCC stage. I have since changed my
assembly procedure to recheck two different ways for tailplane
assembly immediately after installing the tailplane. The manual says
to look for the hook through the little window. But, the most obvious
way is to examine the range of motion of the tailplane for correct,
full travel. The PCC catches it also, with some obvious banging.

After assembly, I corral someone and teach them how to do a Critical
Assembly Check on my ship (and offer to do theirs!). There is actually
a Critical Assembly Checklist in the manual. Then of course I tell
them all the ways the tailplane will look wrong when not put together
correctly. Then we do a PCC. Then I feel like I have a properly
assembled ship.

There are many ways improper assemblies can be caught, I like to use
as many as possible to decrease the odds that any mistakes I make get
through.

Assembly (me)
Check each system after assembled, wing pin & safety pin, spoiler
l'Hotelliers and safety pins, ailerons and safety pins, tailplane.
(me)
Critical Assembly Check (someone else)
Positive Control Check (someone else with me)

Regards,
John Gilbert
Std. Cirrus s/n 266 PY
Seattle, WA, USA