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joe
December 16th 04, 03:27 AM
I am wondering what is involved with trailering and setting up an
average (popular model) glider. Can one reasonable expect to park the
car, unload the trailer, and have glider ready to fly in under
90minutes? Does it usually take two people? Do gliders ever have
wings separate in flight due to weak attachment points?

Bill Daniels
December 16th 04, 04:05 AM
"joe" > wrote in message
oups.com...
> I am wondering what is involved with trailering and setting up an
> average (popular model) glider. Can one reasonable expect to park the
> car, unload the trailer, and have glider ready to fly in under
> 90minutes?

A lot of people can do it alone under 30 minutes with simple assembly aids.

Does it usually take two people?

Not always, but it can help.

> Do gliders ever have wings separate in flight due to weak attachment
points?

If the wings ever separate, it won't be at the attachment points. At least,
I've never heard of it.

Bill Daniels

John Giddy
December 16th 04, 10:58 AM
On Thu, 16 Dec 2004 04:05:33 GMT, Bill Daniels wrote:

> "joe" > wrote in message
> oups.com...
>> I am wondering what is involved with trailering and setting up an
>> average (popular model) glider. Can one reasonable expect to park the
>> car, unload the trailer, and have glider ready to fly in under
>> 90minutes?
>
> A lot of people can do it alone under 30 minutes with simple assembly aids.
>
> Does it usually take two people?
>
> Not always, but it can help.
>
>> Do gliders ever have wings separate in flight due to weak attachment
> points?
>
> If the wings ever separate, it won't be at the attachment points. At least,
> I've never heard of it.
>
> Bill Daniels

Bill,
Wasn't there a fatal just a few years ago where one of the wing pins
in a DG<something> came out because the safety latch became
delaminated from the inside of the fuselage? Wing flexure in rough
conditions caused the pin to work out, as I remember.
John G.

Ken Kochanski (KK)
December 16th 04, 12:05 PM
30 Minutes is typical ... sub 15 minutes is possible with an
experienced crew.

You can purchase or build one-person assembly aids to allow you to do
it alone. Some people are very practiced at this and can put together a
glider just about as quickly as a two-person team.

The attachment points have been designed and tested to fail at loads
well above those you are expected to encounter in flight when you are
operating the glider according to published/certified guidelines. Weak
attachment points are usually never cited as a accident issue ... pilot
error in controlling the glider ... or in hookig up/attaching the
flight controls during assembly ... are the typical causes of
structural/control failures. Most new glider designs now have
automatic control hookups, so when you install wings and elevators, the
control surfaces are properly connected to the cockpit. Even so, a
final check is used to insure the assembly is correct and the control
surfaces function properly.

KK

Bill Daniels
December 16th 04, 03:04 PM
"T o d d P a t t i s t" > wrote in
message ...
> John Giddy > wrote:
>
> >Wasn't there a fatal just a few years ago where one of the wing pins
> >in a DG<something> came out because the safety latch became
> >delaminated from the inside of the fuselage? Wing flexure in rough
> >conditions caused the pin to work out, as I remember.
>
> A DG400 lost its wings a few years ago. It was piloted by
> Fred Jacobs and at an age when most of us have been retired
> for 10-20 years, he successfully made his first parachute
> jump when the wings decided to depart. Delamination of the
> safety latch was suspected, but I don't think anyone knows
> for sure.
>

I started to write that I was dubious about the wing pins working their way
out since they would be locked in place by shear loads. Then I thought
about it more.

For those gliders where the removable pins merely hold the wings against
sliding out of the fuselage and the spar end spigot pins take the actual
bending loads, there is no shear load on the removable pins. They could
indeed work their way out.

My Nimbus uses a single 50mm diameter pin that does take shear loads so it's
hard to see it working out. However, I'll safety it anyway.

Bill Daniels

December 16th 04, 05:42 PM
I can reliably pull up to the gliderport and be on the runway, strapped
in, ready for a tow, in an hour. This is with an LS6b (manual
hookups), two people (the other person needed for 5 minutes max), Cobra
trailer, and not adding any water ballast. It does include taping,
loading batteries, parachute, drinking water, etc., washing, and
cleaning the canopy inside and out. Rigging the plane is usually the
quickest thing to do, expecially if you have auto hookups - maybe 15
minutes from pulling up to done. What takes more time (and which many
people seem to overlook when saying how quick they can rig) is a decent
tape job and a good wash. Add water ballast and you may have another
30 minutes. I would challenge anyone who says they can be ready to go
in 15 minutes to a race...but let them fly their own planes!

I like to give myself two hours from driving up to launching, so I'm
not rushed and have time to do a little flight planning (looking at the
sky, mainly!).

I don't worry about my wings coming off - I worry about spam can
drivers who don't look out the window.

Kirk
66

Ralph Jones
December 16th 04, 07:55 PM
On 15 Dec 2004 19:27:39 -0800, "joe" > wrote:

>I am wondering what is involved with trailering and setting up an
>average (popular model) glider. Can one reasonable expect to park the
>car, unload the trailer, and have glider ready to fly in under
>90minutes? Does it usually take two people? Do gliders ever have
>wings separate in flight due to weak attachment points?

As others have answered, I'd say 90 minutes is just about right for
the COMPLETE job of making the ship ready. As for the assembly itself,
two people can typically do it in 15 minutes -- and six people can do
it in an hour...;-)

John Giddy
December 16th 04, 10:52 PM
On Thu, 16 Dec 2004 15:04:55 GMT, Bill Daniels wrote:

> "T o d d P a t t i s t" > wrote in
> message ...
>> John Giddy > wrote:
>>
>>>Wasn't there a fatal just a few years ago where one of the wing pins
>>>in a DG<something> came out because the safety latch became
>>>delaminated from the inside of the fuselage? Wing flexure in rough
>>>conditions caused the pin to work out, as I remember.
>>
>> A DG400 lost its wings a few years ago. It was piloted by
>> Fred Jacobs and at an age when most of us have been retired
>> for 10-20 years, he successfully made his first parachute
>> jump when the wings decided to depart. Delamination of the
>> safety latch was suspected, but I don't think anyone knows
>> for sure.
>>
>
> I started to write that I was dubious about the wing pins working their way
> out since they would be locked in place by shear loads. Then I thought
> about it more.
>
> For those gliders where the removable pins merely hold the wings against
> sliding out of the fuselage and the spar end spigot pins take the actual
> bending loads, there is no shear load on the removable pins. They could
> indeed work their way out.
>
> My Nimbus uses a single 50mm diameter pin that does take shear loads so it's
> hard to see it working out. However, I'll safety it anyway.
>
> Bill Daniels

Bill, I hope that your grammar is confusing. I read your last sentence
to indicate that you do not currently safety the main pin, but will do
so in future. I hope I am wrong !!!
The main pin in gliders like the Nimbus, Std Cirrus etc. is under
strong continuous shear load in flight in calm air. However in severe
turbulence, I can envisage the load reversing frequently, and with a
small amount of fore and aft movement, "walking" the pin out.
The DG uses two large pins in shear to connect the wings, with no pins
in the ends of the spars. Only a single spar extension on each wing
which overlaps the other for the joint, so such "walking" of a pin is
probably more likely than with the Schempp-Hirth design which uses a
forked end on one spar end and a single end on the other with a pin to
locate its tip in the opposite root rib.
Please always use a safety pin !
Cheers, John G.

Bill Daniels
December 16th 04, 11:40 PM
"John Giddy" > wrote in message
.. .
> > I started to write that I was dubious about the wing pins working their
way
> > out since they would be locked in place by shear loads. Then I thought
> > about it more.
> >
> > For those gliders where the removable pins merely hold the wings against
> > sliding out of the fuselage and the spar end spigot pins take the actual
> > bending loads, there is no shear load on the removable pins. They could
> > indeed work their way out.
> >
> > My Nimbus uses a single 50mm diameter pin that does take shear loads so
it's
> > hard to see it working out. However, I'll safety it anyway.
> >
> > Bill Daniels
>
> Bill, I hope that your grammar is confusing. I read your last sentence
> to indicate that you do not currently safety the main pin, but will do
> so in future. I hope I am wrong !!!

You are right. I've always safetied the main pin on the logic that since
there's a bracket the designer must have thought it necessary. Not
something that calls for experimentation.

Bill Daniels

December 17th 04, 04:16 PM
As I recall, there was just such an accident back in the early '70s at
Minden, NV during the U.S. Nationals. During a high-speed starting run,
both wing pins worked their way out and the wings departed the glider,
turning the fuselage into a missle...from which the pilot bailed out
successfully. I could have my facts wrong (which might explain why no
one else has mentioned this) but I believe the cause was determined
(suspected?) to be the main wing pins not being safetied. One notable
thing was that not only was the pilot obviously at risk when this
happened but also numerous crews/spectators. At least one of the major
pieces hit the airport very close to the crowded takeoff line.

Chip Bearden
ASW 24 "JB"

> "John Giddy" > wrote in message
> .. .
> > > I started to write that I was dubious about the wing pins working
their
> way
> > > out since they would be locked in place by shear loads. Then I
thought
> > > about it more.
> > >
> > > For those gliders where the removable pins merely hold the wings
against
> > > sliding out of the fuselage and the spar end spigot pins take the
actual
> > > bending loads, there is no shear load on the removable pins.
They could
> > > indeed work their way out.
> > >
> > > My Nimbus uses a single 50mm diameter pin that does take shear
loads so
> it's
> > > hard to see it working out. However, I'll safety it anyway.
> > >
> > > Bill Daniels
> >
> > Bill, I hope that your grammar is confusing. I read your last
sentence
> > to indicate that you do not currently safety the main pin, but will
do
> > so in future. I hope I am wrong !!!
>
> You are right. I've always safetied the main pin on the logic that
since
> there's a bracket the designer must have thought it necessary. Not
> something that calls for experimentation.
>
> Bill Daniels

LAS
December 17th 04, 10:40 PM
"joe" > wrote in message
oups.com...
> I am wondering what is involved with trailering and setting up an average
(popular model) glider.<

As we lawyers reply to most questions... "It depends".
It depends on the trailer fixtures and how easy, or difficult, they make it
to move your glider parts around.
It depends on whether your glider has automatic control connections. If
not, it further depends on what type of connections the glider has.

> Can one reasonable expect to park the car, unload the trailer, and have
glider ready to fly in under 90minutes? <

Again, it depends on the glider. I used to own a 2002 Glasflugel that I
could assemble, tape, preflight and be ready to stage in 45 minutes. It
took an hour if I didn't have a helper.

<<Does it usually take two people?>>

Yes. unless you have some type of one-man rigging aid. Some gliders,
particualrly those with heavy wing panels or difficult control connections
will require a third person to assemble.

<Do gliders ever have wings separate in flight due to weak attachment
points?>

I don't know of any instances of gliders breaking at the assembly point.
Maybe someone who's been in this a lot longer than I have can answer that.

59
December 26th 04, 11:10 PM
At the scene of a control failure accident, I noted an unusual breakage
pattern in the canopy. The glider had crashed during a controled landing
into trees, shearing off one wing and coming to rest on the bank of a creek.
The spars remained attached, but one pin was missing. I followed the general
direction of the missing pin through the canopy and about 5 paces out into
the creek where I found it on a rocky bottom. It had apparently ejected on
impact with enough force to break off a piece of the canopy and still
continue some 5 to 10 feet from the fuselage. Fortunately, it did not hit
the pilot. I didn't think to inspect the safety (a sprung hook), to see if
it was damaged (in place on impact) or undamaged.


> wrote in message
oups.com...
> As I recall, there was just such an accident back in the early '70s at
> Minden, NV during the U.S. Nationals. During a high-speed starting run,
> both wing pins worked their way out and the wings departed the glider,
> turning the fuselage into a missle...from which the pilot bailed out
> successfully. I could have my facts wrong (which might explain why no
> one else has mentioned this) but I believe the cause was determined
> (suspected?) to be the main wing pins not being safetied. One notable
> thing was that not only was the pilot obviously at risk when this
> happened but also numerous crews/spectators. At least one of the major
> pieces hit the airport very close to the crowded takeoff line.
>
> Chip Bearden
> ASW 24 "JB"
>
> > "John Giddy" > wrote in message
> > .. .
> > > > I started to write that I was dubious about the wing pins working
> their
> > way
> > > > out since they would be locked in place by shear loads. Then I
> thought
> > > > about it more.
> > > >
> > > > For those gliders where the removable pins merely hold the wings
> against
> > > > sliding out of the fuselage and the spar end spigot pins take the
> actual
> > > > bending loads, there is no shear load on the removable pins.
> They could
> > > > indeed work their way out.
> > > >
> > > > My Nimbus uses a single 50mm diameter pin that does take shear
> loads so
> > it's
> > > > hard to see it working out. However, I'll safety it anyway.
> > > >
> > > > Bill Daniels
> > >
> > > Bill, I hope that your grammar is confusing. I read your last
> sentence
> > > to indicate that you do not currently safety the main pin, but will
> do
> > > so in future. I hope I am wrong !!!
> >
> > You are right. I've always safetied the main pin on the logic that
> since
> > there's a bracket the designer must have thought it necessary. Not
> > something that calls for experimentation.
> >
> > Bill Daniels
>

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