How to suspend a glider?

On Oct 7, 9:11*am, Tim Taylor wrote:
On Oct 7, 8:30*am, Adam wrote:



On Oct 7, 1:28*am, wrote:

Hi all,
Has anyone out there ever suspended a glider in the air without
resorting to the conventional method of airflow over the wings? I have
an opportunity to hang both of my Grob 103's in two malls over the
holiday season. I am pushing for having a Santa in the back and a
Rudolf leaning forward in the front, scarf trailing. Both canopies
will be off. I will have a Glider Ride Gift Certificate booth [not
quite directly] underneath. Some of you may have seen my Mall
Experiment article in the June 2008 issue of Soaring. Well, I'm
experimenting some more!
My first thought, unencumbered by either engineering training or good
advice, is to fabricate a heavy duty, white canvas sling, maybe 2 feet
wide, that would go where the fuselage dolly goes, in front of the
wings and as far aft as possible. The CG hook mechanism could be used
to attach to it also to protect against slippage. The sling would be
sewn proffessionally, providing a pair of rip-free, foolproof,
attachment points on each side. The remaining 50 lbs on the tail could
be handled with a wire running from this central sling support cable
45 degrees down to the horizontal stab attachment bolt at the top of
the verticle stab. The wings could have wires running from the wing
tip skid/tie downs to this central sling support cable at about 45
degrees also.
Thoughts?
Clearly the mall engineers and their insurance underwriters are going
to have the last word, but if any of you have advice/experience/
thoughts, I'd sure appreciate hearing from you. Oh yeah, the 103
weighs in at 850 lbs.
Thanks in advance,
Don Ingrahamhttp://www.crosscountrysoaring.com

As Paul mentioned, the Stanton rig has been in use for many years - it
uses two straps about 6" wide, one in front and one behind the wing
and an I-beam frame above to tie it all together to the lift hoist. It
all looks very heavy duty.

I've been told there is a Std Cirrus suspended in a building somewhere
in downtown Minneapolis - you may want to check that out.

And there is a Std Cirrus mounted upside down on a steep angle to the
inside roof at Gwyn's High Alpine mid-mountain restaurant in Snowmass
- very cool!

Rather than engineer your own sling, there are plenty of industrial
lifting straps out there that are rated for whatever weight you want
to lift to many thousand of pounds. You can get custom straps made too
- a quick web search (no affiliation):

http://www.yellowslings.com/?mfss=go...gs&mfsa=nylons...

With regards to satisfying the mall insurance guy, my guess is he will
demand a P.E. sign-off on the entire mounting system.

I look forward to seeing the dramatic results!

/Adam
I've been told there is a Std Cirrus suspended in a building somewhere
in downtown Minneapolis - you may want to check that out.

If my memory is correct it was a Grob 102 and it was in Butler
Square. *It was there when I lived in Minneapolis around 1993. *There
was an image in Soaring during that period.

What you want for the straps are called "recovery straps". *You should
be able to buy a pair off the shelf for the strength and length you
need.

Thanks to google:

It was a Speed Astir

http://www.stevendahlman.com/pictorial/mpls07.htm

http://www.butlersquare.com/

go to photos (I can't get them to play but maybe someone can)

I use a couple of 12" wide nylon slings (McMaster-Carr) and cheapo Harbor
Freight electric hoists to lift my ASH26E in the hangar. The width of the
nylon straps is overkill, but I wanted to spread the load, one in front of
the wing and the other under the engine compartment.

I use a painter to the wingtip if I have fuel in the wing tanks as the fuel
will drain to the low wing and then it'll get really low! There's very
little load on the painter.

To suspend a glider in a mall, you might consider using manual come-alongs
for the lifting, suspending them using nylon straps over existing steel
beams and reaching the come alongs either with high A-frame ladders or a
man-lift. Or perhaps the glider could be lifted into position using a larger
lift platform with cradle attached?

In any case, it may be way easier to get approval for all this if the glider
is roped off so people can't get under the thing. I can't imagine a fire
dept or other safety agency approving it otherwise, or without engineering
analysis etc. Besides, most of the slings and other hardware needed for this
will be labeled as "not intended for overhead lifting" etc.

bumper

wrote in message
...
Hi all,
Has anyone out there ever suspended a glider in the air without
resorting to the conventional method of airflow over the wings?

Thanks for the ideas and contact information!

Tim, the URL you sent me off-line for the Tree Straps appears to solve
that part - https://www.expeditionexchange.com/straps/
Thanks!

It just occurred to me that if the canopies are off, it becomes
possible to connect inside the fuselage - perhaps a strap under the
front drag-spar carry-through, just behind the back seat. That would
be more elegant in appearance (the overall goal) than big straps under
the belly and would put the load where it was designed to go. It could
even run under the spars I guess, with a little forward triangulation
to allow for a vertical exit.
Frank, you're right that a strap a foot or so ahead of the main wheel
would make the tail weight more than 50 lbs.. It wieghs 45lbs just
sitting on the main.
Hmmm....

Don

On Oct 7, 10:55*am, "bumper" wrote:
I use a couple of 12" wide nylon slings (McMaster-Carr) and cheapo Harbor
Freight electric hoists to lift my ASH26E in the hangar. The width of the
nylon straps is overkill, but I wanted to spread the load, one in front of
the wing and the other under the engine compartment.

I use a painter to the wingtip if I have fuel in the wing tanks as the fuel
will drain to the low wing and then it'll get really low! There's very
little load on the painter.

To suspend a glider in a mall, you might consider using manual come-alongs
for the lifting, suspending them using nylon straps over existing steel
beams and reaching the come alongs either with high A-frame ladders or a
man-lift. Or perhaps the glider could be lifted into position using a larger
lift platform with cradle attached?

In any case, it may be way easier to get approval for all this if the glider
is roped off so people can't get under the thing. I can't imagine a fire
dept or other safety agency approving it otherwise, or without engineering
analysis etc. Besides, most of the slings and other hardware needed for this
will be labeled as "not intended for overhead lifting" etc.

bumper

wrote in message

...



Hi all,
Has anyone out there ever suspended a glider in the air without
resorting to the conventional method of airflow over the wings?- Hide quoted text -

- Show quoted text -

Dang. Good point. In fact, I've been dealing with the mall leasing
agent up until now. Before spending any more time on this, it would be
smart for me to get all the way through to the workers and the
lawyers. I'm not too excited about a floor display though (they break
easy and fix hard).
Don

On Oct 7, 10:54*am, Tim Taylor wrote:
On Oct 7, 9:11*am, Tim Taylor wrote:





On Oct 7, 8:30*am, Adam wrote:

On Oct 7, 1:28*am, wrote:

Hi all,
Has anyone out there ever suspended a glider in the air without
resorting to the conventional method of airflow over the wings? I have
an opportunity to hang both of my Grob 103's in two malls over the
holiday season. I am pushing for having a Santa in the back and a
Rudolf leaning forward in the front, scarf trailing. Both canopies
will be off. I will have a Glider Ride Gift Certificate booth [not
quite directly] underneath. Some of you may have seen my Mall
Experiment article in the June 2008 issue of Soaring. Well, I'm
experimenting some more!
My first thought, unencumbered by either engineering training or good
advice, is to fabricate a heavy duty, white canvas sling, maybe 2 feet
wide, that would go where the fuselage dolly goes, in front of the
wings and as far aft as possible. The CG hook mechanism could be used
to attach to it also to protect against slippage. The sling would be
sewn proffessionally, providing a pair of rip-free, foolproof,
attachment points on each side. The remaining 50 lbs on the tail could
be handled with a wire running from this central sling support cable
45 degrees down to the horizontal stab attachment bolt at the top of
the verticle stab. The wings could have wires running from the wing
tip skid/tie downs to this central sling support cable at about 45
degrees also.
Thoughts?
Clearly the mall engineers and their insurance underwriters are going
to have the last word, but if any of you have advice/experience/
thoughts, I'd sure appreciate hearing from you. Oh yeah, the 103
weighs in at 850 lbs.
Thanks in advance,
Don Ingrahamhttp://www.crosscountrysoaring.com

As Paul mentioned, the Stanton rig has been in use for many years - it
uses two straps about 6" wide, one in front and one behind the wing
and an I-beam frame above to tie it all together to the lift hoist. It
all looks very heavy duty.

I've been told there is a Std Cirrus suspended in a building somewhere
in downtown Minneapolis - you may want to check that out.

And there is a Std Cirrus mounted upside down on a steep angle to the
inside roof at Gwyn's High Alpine mid-mountain restaurant in Snowmass
- very cool!

Rather than engineer your own sling, there are plenty of industrial
lifting straps out there that are rated for whatever weight you want
to lift to many thousand of pounds. You can get custom straps made too
- a quick web search (no affiliation):

http://www.yellowslings.com/?mfss=go...gs&mfsa=nylons...

With regards to satisfying the mall insurance guy, my guess is he will
demand a P.E. sign-off on the entire mounting system.

I look forward to seeing the dramatic results!

/Adam
I've been told there is a Std Cirrus suspended in a building somewhere
in downtown Minneapolis - you may want to check that out.

If my memory is correct it was a Grob 102 and it was in Butler
Square. *It was there when I lived in Minneapolis around 1993. *There
was an image in Soaring during that period.

What you want for the straps are called "recovery straps". *You should
be able to buy a pair off the shelf for the strength and length you
need.

Thanks to google:

It was a Speed Astir

http://www.stevendahlman.com/pictorial/mpls07.htm

http://www.butlersquare.com/

go to photos (I can't get them to play but maybe someone can)- Hide quoted text -

- Show quoted text -


Interesting - James H. Binger (ex-CEO of Honeywell and philanthropist)
is listed as the owner. I wonder from where he flew it locally?

http://www.butlersquare.com/speedastir.htm

Don,

It occurs to me that the biggest collection of hanging aircraft anywhere is
in the Simthsonian Air & Space Museum. I wonder if you could get a curator
to give you some tips. It might be worth a phone call.

Attaching to the inside structure would be my first choice for asthetic
reasons. I'm not sure how strong the anchor points are but the rear seat
belts might be useful. There's four structural anchor points to work with.

Bill Daniels
wrote in message
...
Thanks for the ideas and contact information!

Tim, the URL you sent me off-line for the Tree Straps appears to solve
that part - https://www.expeditionexchange.com/straps/
Thanks!

It just occurred to me that if the canopies are off, it becomes
possible to connect inside the fuselage - perhaps a strap under the
front drag-spar carry-through, just behind the back seat. That would
be more elegant in appearance (the overall goal) than big straps under
the belly and would put the load where it was designed to go. It could
even run under the spars I guess, with a little forward triangulation
to allow for a vertical exit.
Frank, you're right that a strap a foot or so ahead of the main wheel
would make the tail weight more than 50 lbs.. It wieghs 45lbs just
sitting on the main.
Hmmm....

Don

Bill Daniels wrote:

It occurs to me that the biggest collection of hanging aircraft anywhere is
in the Simthsonian Air & Space Museum. I wonder if you could get a curator
to give you some tips. It might be worth a phone call.

Dunno. To me, it occurs that the biggest collection of hanging *gliders*
is the Wasserkuppe museum.

http://www.segelflugmuseum.de/was_wi... 1c4f67fa1076

I'm not sure they can give you useful tips, though, as their suspending
method is pretty definitive (drilling holes).

Dang. Good point. In fact, I've been dealing with the mall leasing
agent up until now. Before spending any more time on this, it would be
smart for me to get all the way through to the workers and the
lawyers. I'm not too excited about a floor display though (they break
easy and fix hard).
Don

If the hanged glider idea does not work due to technical/lawyer
challenges, how about a big sturdy (probably steel and hopefully nice
looking...) stand to mount it to that would make it look like a 1:1
scale model, Santa/reindeer and all. (perhaps in a nose low attitude
to show off rosy cheeks and red noses). Off the top of my head, the
main wheel could be removed and the undercarriage hard points used to
rigid mount it to the stand. Aesthetically, I think that would look
better than being slung with thick (possibly brightly colored...)
webbing. The base of the stand would need to be rather large, but
obviously it could be constructed in segments that bolt together on
site.

The 45# tail-weight (main wheel as fulcrum...) can be either designed
into the load stresses of the stand many different ways, or ballasted
out entirely ( I suppose ballasting it out is an option for hanging
too). Supplementary 1/8" wire rope could be strung up off the
wingtips (and possibly the tail too if needed...) to add additional
stability if necessary or desired, with little aesthetic impact. Just
a thought...

-Paul

wrote:
Hi all,
Has anyone out there ever suspended a glider in the air without
resorting to the conventional method of airflow over the wings? I have
an opportunity to hang both of my Grob 103's in two malls over the
holiday season.

Can large metal tabs be placed on the fuselage lift pins before the
wings are attached? That would provide 4 points with the CG in the
middle (mostly). Each tab could have a hole in the top large enough for
the attachment to a cable; the four cables would be brought together,
say, 5 feet above the CG, where the cable from the ceiling beam would
attach to them.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

On Oct 7, 12:48*pm, wrote:
Thanks for the ideas and contact information!

Tim, the URL you sent me off-line for the Tree Straps appears to solve
that part -https://www.expeditionexchange.com/straps/
Thanks!

It just occurred to me that if the canopies are off, it becomes
possible to connect inside the fuselage - perhaps a strap under the
front drag-spar carry-through, just behind the back seat. That would
be more elegant in appearance (the overall goal) than big straps under
the belly and would put the load where it was designed to go. It could
even run under the spars I guess, with a little forward triangulation
to allow for a vertical exit.
Frank, you're *right that a strap a foot or so ahead of the main wheel
would make the tail weight more than 50 lbs.. It wieghs 45lbs just
sitting on the main.
Hmmm....

Don

Hi Don,

By now, you must be wondering just what you got yourself into :-)

After I posted the first mail, it occured to me that the Arnot Mall in
Elmira/Horseheads had a 1-26 hanging from the ceiling for many years.
Haven't been there lately, but I'm sure some Harris Hill folks will
chime in. Since lawyers love precendent, I wonder if it wouldn't be
a good idea to reach out to the Arnot Mall management and see if
they'd be willing to speak to the folks at your mall. At minumum,
they may be able to supply a couple of pictures. Yeah, it's a tube
and steel glider and likely suspnded by the frame behind the pilot
seat, but the John Q. Lawyer probably doesn't know that.

P3