Positive Control Hookup
Robert Nase Johnson
assembly isn't universally employed?
Seems almost criminal that it's not.
Bob Johnson
Al
Al
"Robert Nase Johnson" <b...@oneillpr.com> wrote in message
news:3D6CD815...@oneillpr.com...
Robert Nase Johnson
Well, when the wings and elevator of the Ventus (and I assume other S-H
sailplanes) are assembled, the control hookups on these surfaces
automatically fit into little matching sockets provided in the fuselage
end of the lashup. Voila, no fiddling.
Bad hair days due to crashage from disconnected or unconnected rods and
levers are avoided. In short, if the main spar and elevator pins are can
be inserted, seated, and safetied, you are good to go. Actually, the
elevator pin self-safeties.
Never hurts to still do a PCC, though, stay in practice, may see
something else.
BJ
Al
its amazing really that manufacturer's dont add this as standard.
I mean its not rocket science to add.
Although doesnt Ventus A have hotelliers in it?
Al
"Todd Pattist" <tpat...@DONTSPAMME.snet.net> wrote in message
news:a03qmuo3clnlvbdpn...@4ax.com...
> "Al" <asw17...@bigwings.org> wrote:
> >> Can someone explain again why the Ventus method of positve control
> >> assembly isn't universally employed?
>
> >please enlighten us to what that is?
>
> He's generally referring to automatic control hookups. In
> the Ventus/Schempp-Hirth design a pivoting arm on the
> wingroot has a wheel at the end that fits into a
> corresponding funnel-shaped pivoting capture device in the
> fuselage.
> Todd Pattist - "WH" Ventus C
> (Remove DONTSPAMME from address to email reply.)
Robert Nase Johnson
You may well be right, altho checking NTSB for "Ventus" over the last 22
years, I find 19 reported accidents, including five fatals:
"A" N17KS, Ephrata, WA: Midair,
"B" N240WT, Waitsfield, VT: Turn to final,
"A" N7XT, Middletown, NY: Undetermined,
"C" N418CH, Durango, CO: Landed in trees,
"2B" N80077, Hobbs, NM: Turn to final.
Bob
Todd Pattist wrote:
> Robert Nase Johnson <b...@oneillpr.com> wrote:
>
> >Well, when the wings and elevator of the Ventus (and I assume other S-H
> >sailplanes) are assembled, the control hookups on these surfaces
> >automatically fit into little matching sockets provided in the fuselage
> >end of the lashup. Voila, no fiddling.
> >
> >Bad hair days due to crashage from disconnected or unconnected rods and
> >levers are avoided. In short, if the main spar and elevator pins are can
> >be inserted, seated, and safetied, you are good to go. Actually, the
> >elevator pin self-safeties.
> >
> >Never hurts to still do a PCC, though, stay in practice, may see
> >something else.
>
> Even the Ventus has been misassembled (with fatal results)
> by setting the elevator in place, but not pulling and
> engaging the front catch. I believe it's been done at least
> twice. AFAIK, however, there haven't been any failures of
> the Schempp-Hirth automatic aileron/airbrake connections
> (does anyone else know different?)
Jim H
>be inserted, seated, and safetied, you are good to go. Actually, the
>elevator pin self-safeties.
>
>Never hurts to still do a PCC, though, stay in practice, may see
>something else.
BJ,
If you're advocating that a PCC is not needed on a Ventus, I think you are dead
wrong. Every ship when assembled needs a PCC, regardless of whatever
newfangled gizmos guarantee that the controls are hooked up.
Other points on this thread:
1) I think a PCC is only needed before the first flight of the day as part of
the preflight. It is not part of the pretakeoff check.
2) Too many people don't know how to do a proper PCC.
Jim H.
CFIG
N483SZ
gapagod...@aol.com
Robert Nase Johnson
I'm terribly sorry I left even one person the impression that I advocated that.
BJ
John Giddy
large and costly job to modify them all to automatic control
hook-ups.
Cheers, John G.
"Robert Nase Johnson" <b...@oneillpr.com> wrote in message
news:3D6CD815...@oneillpr.com...
John Giddy
connections. Example: the Std Cirrus which uses L'Hotellier
couplings for ailerons and brakes. Earlier versions also
had a stabiliser connection which had the potential for
incorrect connection of the elevator push rod. (see recent
thread here).
Automatic connections are nice, but if not carefully
designed can add significant friction in the circuit.
Cheers, John G.
"Robert Nase Johnson" <b...@oneillpr.com> wrote in message
news:3D6D0D33...@oneillpr.com...
Bob Johnson
I'm terribly chagrined at the prospect that even one person out there
felt I was pushing for a mass retrofit of the world glider fleet --- 8>)
BJ
Ludovic Launer
New gliders now all have automatic hook up, but it's not always been the
case.
My ASW20 doesn't.
On good thing to replace the hotellier connections is to use the wedekind
"sleeves", this design allows you not to have to insert the pin into the
hotellier. Very useful when you have to rig / unrig at every flight.
Regards,
Ludovic Launer
ludovic...@planeur.net
Andreas Maurer
<tpat...@DONTSPAMME.snet.net> wrote:
>Robert Nase Johnson <b...@oneillpr.com> wrote:
>
>>You may well be right, altho checking NTSB for "Ventus" over the last 22
>>years, I find 19 reported accidents, including five fatals:
>
>At least one accident was outside the U.S. and although my
>post may not have been clear, my intent was to comment on
>misconnection accidents in the Ventus/Discus type tail
>attachment design, not just the Ventus.
>Todd Pattist - "WH" Ventus C
One might add that a very famous german pilot was involved in the
accident you are talking about. He had been interrupted wil assempling
his plane.
Bye
Andreas
Andreas Maurer
wrote:
>Gotcha...
>
>its amazing really that manufacturer's dont add this as standard.
>I mean its not rocket science to add.
It is standard for new designs since a couple of years.
The PW-5 is afaik the only glider in the last 15 years that was
certified without automatic control hookups (at least in Germany this
violates certification rules - I'm not sure if it has a Herman
certification).
Bye
Andreas
Robert Nase Johnson
You're correct that NTSB covers just the domestic scene, leaving a big hole
in our data. However, I did broaden the U.S. search to "Schempp-Hirth", and
found the following reported fatals among all non-Ventus, later model S-H
sailplanes for the past 22 years:
Nimbus, one, undet.
Nimbus 2C, one, turn to final
Discus B, one, midair
Nimbus 4DM, one, spin (2-place, both fatal)
Discus CS, one, stall/spin
Nimbus 3DM, one, ridge (2-place, both fatal)
(Sidebar: 5 Cirruses ---- two, midairs; one, assembly (prelim); one,
ridge; one, landing but pilot walked away, go figure.)
I'm sure our friends across the water have glider accident databases similar
to or better than ours.
To do a halfway definitive study, I would also have to know which later model
ships are equipped with positive control hookups, but this will be tough for
me to find out. Feedback on this thread hints that most current production is
favorably affected.
Does anyone out there know which current offerings on the recently
manufactured sailplane list have positive control hookups?
Seems like this would be a great brochure headline item.
BJ
Todd Pattist wrote:
> Robert Nase Johnson <b...@oneillpr.com> wrote:
>
> >You may well be right, altho checking NTSB for "Ventus" over the last 22
> >years, I find 19 reported accidents, including five fatals:
>
> At least one accident was outside the U.S. and although my
> post may not have been clear, my intent was to comment on
> misconnection accidents in the Ventus/Discus type tail
> attachment design, not just the Ventus.
WilLiscomb
spite of the controls being properly hooked up if it goes together, a PCC is
always a good way to insure that all push/pull rods, bellcranks and pulleys are
secure, connected and operating in a useful and intended manner...
williscomb
Eric Greenwell
>Can someone explain again why the Ventus method of positve control
>assembly isn't universally employed?
Do you mean, compared to the positive control assembly techniques used
by other manufacturers (Schleicher, LS, DG, etc)? Or are you wondering
why other don't use some form of auto hookup for the controls? Or are
you wondering why Schmepp-Hirth doesn't use the Ventus system on their
Nimbus, Discus, etc?
--
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