Tie Down Straps - Help Needed

Hi,

I am trying to provide a very high quality sailplane tie-down kit and I need
the help of this very knowledgeable group.

A customer of mine recommended that I buy and sell the tie-down system that
Cobra offers. I did some research and talked to Cobra about it. I came to
the conclusion that I liked their tie-down straps, but decided not to buy
their stakes but rather to use "The CLAW" anchoring system. I bought a
batch of the tie-down straps from Cobra and sold one set to the customer
that had started the process. The good news is that the straps are
extremely nice and rugged. They are a little over 15 feet long and have
very nice foam padding on about 5 feet of the strap. There is a very rugged
metal cam buckle at one end of the strap. They will work very nicely with
The CLAW system. When used with a pair of wing stands they will hold the
wings down very securely.

The bad news is that the straps are extremely expensive (in my opinion) for
what they are. To make a fair profit I will need to sell them for $50 each.
I can buy similar 1" straps at my local hardware store for much less, but
they wouldn't have the very nice padding found on the Cobra provided straps.

So, the reason for this post is to see if any of you have any suggestions on
sources for the straps - with metal buckles and padding. The straps have
the words "Sail & Fly By Sails Products" sewed into the strap. I have had
no luck finding the source or any reference to the straps using Google.
Does anyone know where they are made? The name implies that they are made
for both the sailing and aviation markets. I have no idea where in the
world they are made. My guess is that Cobra buys them and marks them up and
then I have to pay for the shipping for the heavy package all the way to my
office in Minnesota, USA.

My goal is to find a lower cost source so I can offer an very high quality
and reasonably priced system for glider pilots. For now, you can see the
very nice, but somewhat pricey option on my web site he
http://www.cumulus-soaring.com/misc....Down_Equipment

Good Soaring,

Paul Remde
Cumulus Soaring, Inc.
http://www.cumulus-soaring.com

I always get tie down stuff from Mac's. They sell a nice strap for $5,
and check out this strap pad-

http://www.macscustomtiedowns.com/product/115/TieDowns


The CLAW- when I looked at this I decided to use flyties (
http://www.flyties.com/ ). The Claw looks like it will hold great as
long as the pulling force is directly up, but if the load moves around
it seems like the device itself would act as a lever with the near
arms prying the far stake up and out. In any case off center loads
will concentrate on individual stakes, perhaps.

Or maybe I just like the flyties better. The tool they give you to
pull the stakes out is really nice.

Google may be your friend. A search for "Sails Products" & Germany
reveal a company called Sails Products Sportartikel based in Baden
Wurttemberg. Contact details (snail mail only) via:

http://www.hotfrog.de/Firmen/SAILS-P...S-Sportartikel

The company doesn't appear to have a website, but you might find an
online phone directory for Germany and reach them that way.

Paul Remde wrote:
Hi,

I am trying to provide a very high quality sailplane tie-down kit and I need
the help of this very knowledgeable group.

A customer of mine recommended that I buy and sell the tie-down system that
Cobra offers. I did some research and talked to Cobra about it. I came to
the conclusion that I liked their tie-down straps, but decided not to buy
their stakes but rather to use "The CLAW" anchoring system. I bought a
batch of the tie-down straps from Cobra and sold one set to the customer
that had started the process. The good news is that the straps are
extremely nice and rugged. They are a little over 15 feet long and have
very nice foam padding on about 5 feet of the strap. There is a very rugged
metal cam buckle at one end of the strap. They will work very nicely with
The CLAW system. When used with a pair of wing stands they will hold the
wings down very securely.

The bad news is that the straps are extremely expensive (in my opinion) for
what they are. To make a fair profit I will need to sell them for $50 each.
I can buy similar 1" straps at my local hardware store for much less, but
they wouldn't have the very nice padding found on the Cobra provided straps.

So, the reason for this post is to see if any of you have any suggestions on
sources for the straps - with metal buckles and padding. The straps have
the words "Sail & Fly By Sails Products" sewed into the strap. I have had
no luck finding the source or any reference to the straps using Google.
Does anyone know where they are made? The name implies that they are made
for both the sailing and aviation markets. I have no idea where in the
world they are made. My guess is that Cobra buys them and marks them up and
then I have to pay for the shipping for the heavy package all the way to my
office in Minnesota, USA.

My goal is to find a lower cost source so I can offer an very high quality
and reasonably priced system for glider pilots. For now, you can see the
very nice, but somewhat pricey option on my web site he
http://www.cumulus-soaring.com/misc....Down_Equipment

Good Soaring,

Paul Remde
Cumulus Soaring, Inc.
http://www.cumulus-soaring.com

"brianDG303" wrote in message
...
I always get tie down stuff from Mac's. They sell a nice strap for $5,
and check out this strap pad-

http://www.macscustomtiedowns.com/product/115/TieDowns


The CLAW- when I looked at this I decided to use flyties (
http://www.flyties.com/ ). The Claw looks like it will hold great as
long as the pulling force is directly up, but if the load moves around
it seems like the device itself would act as a lever with the near
arms prying the far stake up and out. In any case off center loads
will concentrate on individual stakes, perhaps.

Or maybe I just like the flyties better. The tool they give you to
pull the stakes out is really nice.


FWIW, I know of two gliders totaled as a result of the "claw" pulling out of
the ground. Gliders tend to repeatedly yank at their tiedowns in a storm.
This will weaken the hold of almost any stake system including the "Claw".

Hi Bill,

That is a very strong accusation against the CLAW. Can you please give more
information about the circumstances of the 2 failures? Was the CLAW used
properly? It is designed for straight-up loads - not side-loads. I am
extremely impressed with the design of the CLAW. Until your post I have
heard only positive comments on it. It would seem to me (being a mechanical
engineer) that the CLAW is uniquely designed to grab hold more tightly when
a load is applied (from directly above).

The link to the flyties below does look interesting, but I don't agree that
it would be more robust than the CLAW.

Thanks,

Paul Remde

"Bill Daniels" bildan@comcast-dot-net wrote in message
...

"brianDG303" wrote in message
...
I always get tie down stuff from Mac's. They sell a nice strap for $5,
and check out this strap pad-

http://www.macscustomtiedowns.com/product/115/TieDowns


The CLAW- when I looked at this I decided to use flyties (
http://www.flyties.com/ ). The Claw looks like it will hold great as
long as the pulling force is directly up, but if the load moves around
it seems like the device itself would act as a lever with the near
arms prying the far stake up and out. In any case off center loads
will concentrate on individual stakes, perhaps.

Or maybe I just like the flyties better. The tool they give you to
pull the stakes out is really nice.


FWIW, I know of two gliders totaled as a result of the "claw" pulling out
of the ground. Gliders tend to repeatedly yank at their tiedowns in a
storm. This will weaken the hold of almost any stake system including the
"Claw".

I one of them was Paul Hansen's Sisu 1A in California the other was a
Schweizer in Texas - Houston I think. Anyway there are dozens more stories
of stakes pulling out leading to the distruction of gliders in the history
of gliding.

I don't think it's a matter of mechanical engineering, it's soil
engineering. Stakes will hold in turf or damp soil held together by strong
roots. The dry sand and gravel of western deserts just won't hold a stake
no matter how cleverly it's designed. Even half axle shafts driven in with
a sledge hammer have pulled out. The act of driving in the stake loosens
the soil enough to prevent the stake(s) from holding making the whole
exercise self-defeating.

Take a look at airport tiedowns where there's some liability involved.
These are usually 1/2 - 3/4" steel cable set in several hundred pounds of
concrete at multiple points. Anything less is a short term expediency used
under emergency conditions with no guarantees.

I spent some time working on the problem before giving up on stakes
altogether and working out the "bury the ditty bag" scheme. Even if a
dittybag does pull out of the ground, there's still several hundred pounds
of dirt tied to each wing. Ditty bags and a folding trenching tool weigh
less than stakes too. Why not find a good source of those to sell?

BTW, trenching tools have dug some pretty deep holes. I've been sold by
Marines that it's truly amazing how quick and deep you can dig when being
shot at.

"Paul Remde" wrote in message
news:5sUAk.350834$yE1.314870@attbi_s21...
Hi Bill,

That is a very strong accusation against the CLAW. Can you please give
more information about the circumstances of the 2 failures? Was the CLAW
used properly? It is designed for straight-up loads - not side-loads. I
am extremely impressed with the design of the CLAW. Until your post I
have heard only positive comments on it. It would seem to me (being a
mechanical engineer) that the CLAW is uniquely designed to grab hold more
tightly when a load is applied (from directly above).

The link to the flyties below does look interesting, but I don't agree
that it would be more robust than the CLAW.

Thanks,

Paul Remde

"Bill Daniels" bildan@comcast-dot-net wrote in message
...

"brianDG303" wrote in message
...
I always get tie down stuff from Mac's. They sell a nice strap for $5,
and check out this strap pad-

http://www.macscustomtiedowns.com/product/115/TieDowns


The CLAW- when I looked at this I decided to use flyties (
http://www.flyties.com/ ). The Claw looks like it will hold great as
long as the pulling force is directly up, but if the load moves around
it seems like the device itself would act as a lever with the near
arms prying the far stake up and out. In any case off center loads
will concentrate on individual stakes, perhaps.

Or maybe I just like the flyties better. The tool they give you to
pull the stakes out is really nice.


FWIW, I know of two gliders totaled as a result of the "claw" pulling out
of the ground. Gliders tend to repeatedly yank at their tiedowns in a
storm. This will weaken the hold of almost any stake system including the
"Claw".

Bill Daniels wrote:

FWIW, I know of two gliders totaled as a result of the "claw" pulling out of
the ground. Gliders tend to repeatedly yank at their tiedowns in a storm.
This will weaken the hold of almost any stake system including the "Claw".

For tying down at the gliderport, putting a wing stand on each wing
would considerbly reduce the yanking. For landouts, when you don't have
the stands, I wonder if this could be avoided by using one or two Claws
tied to the main gear, and one other to hold a wing tip on the ground.
Tying to the gear would considerably reduce the repeated yanking.

--
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 Sep 19, 12:57*pm, brianDG303 wrote:
I decided to use flyties *(http://www.flyties.com/).

I've been using a similar product for over 20 years. Got it from
Australia.

The stakes are nylon and have held up amazingly well, sometimes
twisting a bit to get into rocky soil, but so far, never broke one. I
would guess I've used it 10 - 15 times, mostly for overnight tiedown
in benign conditions, but a few times I've had to secure the glider in
gusty conditions while waiting for my crew.

As for straps, I clicked on an ad for "CAM Buckle Straps":
http://www.kingroyusa.com/cargo-cont...FQq4sgodLxW8ew

that showed up in my Google sidebar. Pretty nice bulk pricing at less
than $10 per strap & buckle.

-Tom

On Sep 19, 2:47*pm, "Bill Daniels" bildan@comcast-dot-net wrote:
I one of them was Paul Hansen's Sisu 1A in California the other was a
Schweizer in Texas - Houston I think. *Anyway there are dozens more stories
of stakes pulling out leading to the distruction of gliders in the history
of gliding.

I don't think it's a matter of mechanical engineering, it's soil
engineering. *Stakes will hold in turf or damp soil held together by strong
roots. *The dry sand and gravel of western deserts just won't hold a stake
no matter how cleverly it's designed. *Even half axle shafts driven in with
a sledge hammer have pulled out. *The act of driving in the stake loosens
the soil enough to prevent the stake(s) from holding making the whole
exercise self-defeating.

My Sisu did indeed get pulled out when tied out with the Claw anchors,
but it was really my own fault and not a design flaw. They are
wonderful tiedowns, but like any portable solution they are NOT a
substitute for permanent anchors or proper ground handling. Mine were
in the ground for far too long prior to the big storm. I did have the
tail up on a bucket and the wings on stands, but this did not make up
for the compromised condition of the soil my anchors were in by the
time of the storm. There was an SGS 1-35 tied out right next to my
ship in the exact same manner. His tiedowns held. The difference? Mine
had been in for about 5 months. His only 2. There is no better
portable tiedown system out there, and I still use them today.

Recapping, they had no problem holding a 1-35 into the ground in a
sustained 60+mph headwind (gusting higher...), despite being in the
ground for 2 months, that was completely saturated, soft, and muddy by
the time of the storm. Hmmm, pretty impressive actually!

I have no details of the TX SGS, so I will not comment on that one.

With mine though, like any terrible incident in aviation there was a
chain of events that could have been broken at numerous links. Had I
simply pulled out my tiedowns and re-situated them in fresh earth, had
I opened my spoilers, had I added my second (then dormant) set, had I
de-regged and put it in the trailer...Any one of these solutions would
have made all the difference. Lesson learned : (

Bottom line though, those claw anchors are badd a$$, just use them as
they are supposed to be used. There are NO other portable spike/
dogscrew type anchors that come even close to competing with them for
holding power, ease of installation, and especially in ease of removal
(that I have heard of/seen tested anyways...).

-Paul

PS. I like the ditty bag idea, but there are many places out west
where you would have trouble getting even a full size spade shovel
into the ground let alone one of those army surplus portable shovels,
and you can't guarantee the prospect of finding loose rocks either.
The Claw anchors go in in about one minute apiece in hard ground, and
that is where they can develop their full 1200lb pull rating (they
take ~500lbs apiece to pull out of soft grass turf, close to double
the other styles tested by Sporty's [inc the spikes-through-a-hockey
puck type mentioned in a previous post here...]). The ditty bag
solution however IS light enough to have little excuse for not having
it on hand the ship just in case it may work though...

On Sep 19, 5:38*pm, sisu1a wrote:
On Sep 19, 2:47*pm, "Bill Daniels" bildan@comcast-dot-net wrote: I one of them was Paul Hansen's Sisu 1A in California the other was a
Schweizer in Texas - Houston I think. *Anyway there are dozens more stories
of stakes pulling out leading to the distruction of gliders in the history
of gliding.

I don't think it's a matter of mechanical engineering, it's soil
engineering. *Stakes will hold in turf or damp soil held together by strong
roots. *The dry sand and gravel of western deserts just won't hold a stake
no matter how cleverly it's designed. *Even half axle shafts driven in with
a sledge hammer have pulled out. *The act of driving in the stake loosens
the soil enough to prevent the stake(s) from holding making the whole

I agree with Bill. I did a test with the claw attached to my trailer
jack and the wheel on a scale. The claw pulled out of compacted
decomposed granite in my driveway at about 250 lbs, came completetly
out at 300, but this was aided by weed stop fabric under the DG. The
soil was damp to a great depth due the the Socal rains in January this
year, but not soggy. I doubt that dry, uncompacted sand would do
better.

I have the claw in my Cirrus as an emegency tie down only, I think it
is a good product for that application.

For permanent tie downs nothing like a tire buried with a chain around
it. One the sand is watered down, it is not goining anywhere.

Mike Malis.