Spindelberger wing cuffs for tiedown; severe winds

I want to be able to leave my glider assembled and tied down all
summer, with Jaxida covers on it, but am concerned about how to secure
it against the occasional severe winds we get at Minden.
Spindelberger makes fiberglass wing cuffs that look similar to the
cuff used to attach a wheel under the wing for ground handling, but
that don't have the wheel and that have some hooks on the top to
secure a strap that would go over the top of the cuff and then would
be tied to a metal cable on the ground.

Does anyone have experience with this particular product? I have two
potential concerns. First, will using them on both wings put undue
pressure on the ailerons/flaps? Second, is the cuff rigid enough so
that even in severe winds that try to raise the wing, the rear of the
cuff won't bend down and put unwanted pressure on the ailerons/flaps?

I couldn't figure out how to attach a picture of the Spindelberger
cuffs but, as I mentioned, they look just like the cuff used to hold
the wing wheel for ground handling, with the addition of the loops on
top to hold the straps in place. They cost 178 Euros each, plus
shipping.

If you want to reply privately, I can be reached at


Mitch Polinsky
"MP" N223MP (flying out of Minden in the summer)

Message from Alfred Spindelberger follows:

Some of our customers prefer this glass-fibre wing cuffs as seen in
the attachment. The are foam- padded and have two eyes for the belt.
They are EURO 178 each, including the belt
I recommand to use 2 Wingstands when you tie down your plane.

Mit freundlichen Grüßen
Best Regards,

Alfred Spindelberger

"Mitch Polinsky" wrote in message
...
I want to be able to leave my glider assembled and tied down all
summer, with Jaxida covers on it, but am concerned about how to secure
it against the occasional severe winds we get at Minden.

I can't advise you on the wing cuffs, but use a tail stand to level the
glider and don't forget to add a tiedown to your tow hook. Both of those can
greatly reduce the force on your wing tiedowns, particularly from head-on winds.
Adding that 4th tiedown also gives you a bit of redundancy so that your glider
is not as free to flop around if you lose one of your wing tiedowns.

Vaughn

Your concerns about downward pressure on both flaps & alierons are
well founded. I'd attach the rope to the forward end of the wing cuffs
and then pull forward with both wing ropes. This will require a tail
rope that pulls the other way. Raising the tail is a good idea. I have
seen too many gliders on their back at Minden after the rotor touched
down with an estimated 100 mph gust. Our ships are designed to fly and
they'll do it with or without the pilot on board. On a big bird, you
might consider 4 wing ropes. Personally, I only leave the ship
assembled when I'm spending the night right beside the bird and even
then I have been up checking things at 3:00 AM. Assembling even a big
bird with a wing assembly tool is painless. I use the new "Wing
Rigger", its 3 wheels will roll over rough ground and the third wheel
solves the kick stand issue (can't fall over when wing is lifted off
stand) Google WWW.WingRigger.com I'm not associated with this
product, just appreciate good engineering that solves a problem.
Hope this helps,
JJ

JJ Sinclair wrote:
Your concerns about downward pressure on both flaps & alierons are
well founded. I'd attach the rope to the forward end of the wing cuffs
and then pull forward with both wing ropes. This will require a tail
rope that pulls the other way. Raising the tail is a good idea. I have
seen too many gliders on their back at Minden after the rotor touched
down with an estimated 100 mph gust.

How many upside down gliders from Minden have you repaired over the years?

--
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

When buying wing covers, I'd order pockets sewn in the upper surface for the
length of the wing. The pockets would segmented to hold lengths of pipe foam
insulation to act as spoilers. Velcro tabs would close the ends of the
pockets to keep insulation in place. The pockets should be relatively easy
to add after market.

JJ, I agree with you and defer to your experience. However, I'd be concerned
with tying down the cuffs from the front only. The spar being further back,
wouldn't there be risk of the cuff exerting too much downward pressure on
the unsupported leading edge of the wing?

Many gliders, that live on the Minden ramp, use wing stands to "counter" the
tie down force. The wing stand should be secured in place under the spar so
that it can't move, fall over, or try to attack the underside of the wing.
I've seen crappy tie down jobs that risk the glider and those ships
unfortunate enough to be down wind.

I, and a few others I've seen, will often survey the ramp before an incoming
storm, checking tie-downs and trying to fix those that look shaky. People
that leave their gliders out during real blows are braver than me.

bumper
Minden
QV and MKII

"JJ Sinclair" wrote in message
...
Your concerns about downward pressure on both flaps & alierons are
well founded. I'd attach the rope to the forward end of the wing cuffs
and then pull forward with both wing ropes. This will require a tail
rope that pulls the other way. Raising the tail is a good idea. I have
seen too many gliders on their back at Minden after the rotor touched
down with an estimated 100 mph gust. Our ships are designed to fly and
they'll do it with or without the pilot on board. On a big bird, you
might consider 4 wing ropes. Personally, I only leave the ship
assembled when I'm spending the night right beside the bird and even
then I have been up checking things at 3:00 AM. Assembling even a big
bird with a wing assembly tool is painless. I use the new "Wing
Rigger", its 3 wheels will roll over rough ground and the third wheel
solves the kick stand issue (can't fall over when wing is lifted off
stand) Google WWW.WingRigger.com I'm not associated with this
product, just appreciate good engineering that solves a problem.
Hope this helps,
JJ

JJ, I agree with you and defer to your experience. However, I'd be
concerned
with tying down the cuffs from the front only. The spar being further back,
wouldn't there be risk of the cuff exerting too much downward pressure on
the unsupported leading edge of the wing?

Yes, but that would (could) exert undue pressure on the trailing edge
(ailerons & flaps)
Definitely use a wing stand under the spar with a wide padded area.
The dinky one that came with your Cobra trailer isn't wide enough.



I, and a few others I've seen, will often survey the ramp before an incoming
storm, checking tie-downs and trying to fix those that look shaky. People
that leave their gliders out during real blows are braver than me.

Yep, the last one I saw had two G-103's break loose and one slid up-
side-down into another bird. An intense discussion then ensued about
inadequate tie-downs. Finally a local judge ruled that it had been an
act of nature and the Hit'er didn't owe the Hit'ee any compensation. I
picked it up on the salvage market and she's flying today. BTW, next
winters project is a Puchacz that experienced a sage-brush landing at
Minden. The instructior (smallish gal) pulled the plug at 1000' to
test her student's (big guy) rope-break abilities. An intense
discussion then ensued about which runway would be most appropriate
(left back to 30 or right to 16). They fought and finally nestled (not
so gently) into the sagebrush about halfway between the two runways.
Bad spiral broken boom, but I just found a good rear-end from a spun-
in Puch, a little cut & paste and she'll live to fly again!
:) JJ

On Mar 23, 1:57 pm, JJ Sinclair wrote:
JJ, I agree with you and defer to your experience. However, I'd be
concerned

with tying down the cuffs from the front only. The spar being further back,
wouldn't there be risk of the cuff exerting too much downward pressure on
the unsupported leading edge of the wing?

Yes, but that would (could) exert undue pressure on the trailing edge
(ailerons & flaps)
Definitely use a wing stand under the spar with a wide padded area.
The dinky one that came with your Cobra trailer isn't wide enough.

I, and a few others I've seen, will often survey the ramp before an incoming
storm, checking tie-downs and trying to fix those that look shaky. People
that leave their gliders out during real blows are braver than me.

Yep, the last one I saw had two G-103's break loose and one slid up-
side-down into another bird. An intense discussion then ensued about
inadequate tie-downs. Finally a local judge ruled that it had been an
act of nature and the Hit'er didn't owe the Hit'ee any compensation. I
picked it up on the salvage market and she's flying today. BTW, next
winters project is a Puchacz that experienced a sage-brush landing at
Minden. The instructior (smallish gal) pulled the plug at 1000' to
test her student's (big guy) rope-break abilities. An intense
discussion then ensued about which runway would be most appropriate
(left back to 30 or right to 16). They fought and finally nestled (not
so gently) into the sagebrush about halfway between the two runways.
Bad spiral broken boom, but I just found a good rear-end from a spun-
in Puch, a little cut & paste and she'll live to fly again!
:) JJ

JJ

Do you sell "block time" for your workshop/repair services? Maybe
people tying down their gliders at Minden for long periods of time can
purchase some in advance.

When I've flown the Tropic Bird Duo out of Minden a few times and each
time if it is windy I check the tie downs of nearby gliders. More
usual than not there is something sloppy nearby to re-tie. The local
aluminum can Blanik being poorly tied down on many occasions. Some
owners/clubs are so careless in windy conditions continuously retieing
*their* gliders is frustrating and probably puts off the inevitable
when their glider is going to take out somebody else's expensive toy.
It is almost like we'd do more of a favor to the rest of the community
by towing the glider to the nearest downwind part of the ramp and let
it "go free"....

Darryl

There are (were?) some Black & Decker (?) shop stands available from the bog
box home improvement stores that make far better wing stands than anything
else I've seen. The also make great tie down wing stands. They are made
of square steel tubing, have four feet and infinite vertical adjustment with
a strong adjustment lock. The top is a ~ 12" x 6" flat and tiltable plastic
table. They fold flat for storage/transport. You're probably seen them at
a gliderport since they are getting popular.

I modified my stands so the top tilts on two axis to fit flush with the wing
bottom. I also modified it to accept wing cuffs for tiedown. The stand
gets tied down securely but the wing just gets captured by the cuff. Of
course, the nose and tail get tied down very securely. The wing cuffs
usually just keep the wings from rocking and chock the ailerons but can hold
down a large lifting force if neccessary. There is normally no up or down
force on the wings.

Often airport tie downs are long cables anchored with concrete "dead men"
every so often. If I can arrange it, I will position the wheel right on a
deadman and anchor the wheel axle to it with heavy turnbuckles. This way,
the glider is going nowhere except to rock and swivel. The nose, tail, and
wing tie downs prevent that. My glider has ridden out 75 knot winds secured
this way.

Bill D


"JJ Sinclair" wrote in message
...
JJ, I agree with you and defer to your experience. However, I'd be
concerned
with tying down the cuffs from the front only. The spar being further
back,
wouldn't there be risk of the cuff exerting too much downward pressure on
the unsupported leading edge of the wing?

Yes, but that would (could) exert undue pressure on the trailing edge
(ailerons & flaps)
Definitely use a wing stand under the spar with a wide padded area.
The dinky one that came with your Cobra trailer isn't wide enough.



I, and a few others I've seen, will often survey the ramp before an
incoming
storm, checking tie-downs and trying to fix those that look shaky. People
that leave their gliders out during real blows are braver than me.

Yep, the last one I saw had two G-103's break loose and one slid up-
side-down into another bird. An intense discussion then ensued about
inadequate tie-downs. Finally a local judge ruled that it had been an
act of nature and the Hit'er didn't owe the Hit'ee any compensation. I
picked it up on the salvage market and she's flying today. BTW, next
winters project is a Puchacz that experienced a sage-brush landing at
Minden. The instructior (smallish gal) pulled the plug at 1000' to
test her student's (big guy) rope-break abilities. An intense
discussion then ensued about which runway would be most appropriate
(left back to 30 or right to 16). They fought and finally nestled (not
so gently) into the sagebrush about halfway between the two runways.
Bad spiral broken boom, but I just found a good rear-end from a spun-
in Puch, a little cut & paste and she'll live to fly again!
:) JJ

Do you sell "block time" for your workshop/repair services? Maybe
people tying down their gliders at Minden for long periods of time can
purchase some in advance.


No, but at one time we were accused of running a Grob re-cycle
business, the clubs would bust them up, we purchased them from the
insurance company, repaired them and sell them back to the
clubs...............neat little closed-loop system!

Back to tie-downs, I use a large aluminum cuff (12" X 12" X 1/8") with
a 90 degree flange on top where the strap goes. I had the local tin-
bender make them up, padded with felt and slip it over the inboard end
of the aileron. All the force is forward over the leading edge, then
down to a come-along then around the cable. With a wing-stand on the
tip it works well, but I'd still rather put it in the box and then tie
down the box.
JJ

Ditto on the trailers at Minden! I've seen those twist in the wind
too and they would do a number on either your trailer or tied-down
glider


When I've flown the Tropic Bird Duo out of Minden a few times and each
time if it is windy I check the tie downs of nearby gliders.