Using Plasma Rope For Winch Tows

We recently converted from 3/16 7x9 cable to 3/16 plasma rope on our winch.
"Plasma", made from Honeywell "Spectra" fiber, seems to have some real
advantages over wire or cable. Some benifits include light weight, 11.48lbs
per thousand, (that's not much even converted to metric!!), hollow braid
(no twisting), 5000 lb breaking strength (that a lot even converted to
metric!!), 25% increase in launch heights. We operate from asphalt and
it seems to be holding up wery well. Expensive? Yes! However in our
environment it promises to far outlast steel which would make it cheaper
in the long run plus the added benifits. Sorry this sounds like a commerical
I was just so tired of that !@#$@#%%^# wire. If anyone else has any experience
with this stuff is there anything we should be looking out for?

Happy Winching,
Craig-

"Craig Freeman" wrote in message
...
We recently converted from 3/16 7x9 cable to 3/16 plasma rope on our
winch.
"Plasma", made from Honeywell "Spectra" fiber, seems to have some real
advantages over wire or cable. Some benifits include light weight,
11.48lbs
per thousand, (that's not much even converted to metric!!), hollow braid
(no twisting), 5000 lb breaking strength (that a lot even converted to
metric!!), 25% increase in launch heights. We operate from asphalt and
it seems to be holding up wery well. Expensive? Yes! However in our
environment it promises to far outlast steel which would make it cheaper
in the long run plus the added benifits. Sorry this sounds like a
commerical
I was just so tired of that !@#$@#%%^# wire. If anyone else has any
experience
with this stuff is there anything we should be looking out for?

Happy Winching,
Craig-

You should be looking out for:
1. A lot of fun not interrupted by wire tangles.
2. A lot more soaring from the higher release heights.
3. A lot more soaring from the lower costs of the launch.
4. A lot fewer band-aids consumed due to fewer wire cuts on your hands.
5. No wire failures due to rust.

The stuff gets ugly and fuzzy as it wears out so you have a lot of visual
warning long before it gets too weak to use. BTW, I think washing it
occasionally might extend the usable life - you'll have to figure out how to
do that.

I just checked (again) the maximum safe working load of 3/16" 7x7 steel.
It's about 900 pounds if there are no dynamic loads. Spectra is WAY
stronger than that and it doesn't seem to be as sensitive to dynamic loads.

Thanks for the report.

Bill Daniels

This is very interesting to me - I am building a winch, and have been
thinking (agonizing) over the best cable to buy. Can you provide a
reference where I can find more information, and also tell me where
you bought yours? Thanks

How does one splice it you get a cable break or a birds
nest on the winch drum and need to cut it to untangle?






At 22:54 28 July 2003, Bill Daniels wrote:

'Craig Freeman' wrote in message
m...
We recently converted from 3/16 7x9 cable to 3/16
plasma rope on our
winch.
'Plasma', made from Honeywell 'Spectra' fiber, seems
to have some real
advantages over wire or cable. Some benifits include
light weight,
11.48lbs
per thousand, (that's not much even converted to metric!!),
hollow braid
(no twisting), 5000 lb breaking strength (that a lot
even converted to
metric!!), 25% increase in launch heights. We operate
from asphalt and
it seems to be holding up wery well. Expensive? Yes!
However in our
environment it promises to far outlast steel which
would make it cheaper
in the long run plus the added benifits. Sorry this
sounds like a
commerical
I was just so tired of that !@#$@#^# wire. If anyone
else has any
experience
with this stuff is there anything we should be looking
out for?

Happy Winching,
Craig-

You should be looking out for:
1. A lot of fun not interrupted by wire tangles.
2. A lot more soaring from the higher release heights.
3. A lot more soaring from the lower costs of the launch.
4. A lot fewer band-aids consumed due to fewer wire
cuts on your hands.
5. No wire failures due to rust.

The stuff gets ugly and fuzzy as it wears out so you
have a lot of visual
warning long before it gets too weak to use. BTW,
I think washing it
occasionally might extend the usable life - you'll
have to figure out how to
do that.

I just checked (again) the maximum safe working load
of 3/16' 7x7 steel.
It's about 900 pounds if there are no dynamic loads.
Spectra is WAY
stronger than that and it doesn't seem to be as sensitive
to dynamic loads.

Thanks for the report.

Bill Daniels

At Auckland gliding club we are using plain standard rope (aerotow)and find
this works just as well as the more expensive spectra and others like it.The
only difference is in the initial lift off the ground and rotation .The rope
is more elastic and if you do not get load on the cable quickly and maintain
it, an oscillation can start between glider and winch. result: slow fast
slow fast etc launch. The main advantage is its cheap and available
everywhere.
Splicing is the same as aero tow ropes but double the length.
We use the correct weak link for the a/c type
We have found the increase in height is roughly the same as spectra and
others like it.
gary

"Craig Freeman" wrote in message
...
We recently converted from 3/16 7x9 cable to 3/16 plasma rope on our
winch.
"Plasma", made from Honeywell "Spectra" fiber, seems to have some real
advantages over wire or cable. Some benifits include light weight,
11.48lbs
per thousand, (that's not much even converted to metric!!), hollow braid
(no twisting), 5000 lb breaking strength (that a lot even converted to
metric!!), 25% increase in launch heights. We operate from asphalt and
it seems to be holding up wery well. Expensive? Yes! However in our
environment it promises to far outlast steel which would make it cheaper
in the long run plus the added benifits. Sorry this sounds like a
commerical
I was just so tired of that !@#$@#%%^# wire. If anyone else has any
experience
with this stuff is there anything we should be looking out for?

Happy Winching,
Craig-

Do you have any idea how it stacks up cost wise compared
to wire rope?
i.e. twice, three. four times as expensive??
Thanks.


At 22:36 28 July 2003, Craig Freeman wrote:
We recently converted from 3/16 7x9 cable to 3/16 plasma
rope on our winch.
'Plasma', made from Honeywell 'Spectra' fiber, seems
to have some real
advantages over wire or cable. Some benifits include
light weight, 11.48lbs
per thousand, (that's not much even converted to metric!!),
hollow braid
(no twisting), 5000 lb breaking strength (that a lot
even converted to
metric!!), 25% increase in launch heights. We operate
from asphalt and
it seems to be holding up wery well. Expensive? Yes!
However in our
environment it promises to far outlast steel which
would make it cheaper
in the long run plus the added benifits. Sorry this
sounds like a commerical
I was just so tired of that !@#$@#^# wire. If anyone
else has any experience
with this stuff is there anything we should be looking
out for?

Happy Winching,
Craig-

Simon Walker wrote in message ...
Do you have any idea how it stacks up cost wise compared
to wire rope?
i.e. twice, three. four times as expensive??
Thanks.


Its three to four times as much. However, after having experienced
the frustrastions associated with wire for the last two years, this
is like heaven. We pull on a paved runway. Any wire splice or small
kink wears at an extrodinary rate. Plasma rope lays flat and does not
kink,
the light wieght reduces effect of friction on the pull and allows
for the rope to become airborn much quicker all reducing the wear
factor. In the long run Plasma may be cost effective even without the
added benifits of ease of use, added launch hieght ect. . Plasma has a
very small tendency to "birds
nest" as it has very little stretch so no recoil if released
under tension. Also it is relaxed on the spool so it does not try
to grow if the speed suddenly slows on the pull out. Our winch has a
48" drum and no level wind. Plasma does not self level as well as wire
did however it is satisfactory. More info on Plasma here
www.thecortlandcompanies.com/psrope/ .

Craig-

"Plasma Rope"
Brand name?
Mfr.?
Source?
Thanks.
Cheers!

In article ,
(Craig Freeman) wrote:

We recently converted from 3/16 7x9 cable to 3/16 plasma rope on our winch.
"Plasma", made from Honeywell "Spectra" fiber, seems to have some real
advantages over wire or cable. Some benifits include light weight, 11.48lbs
per thousand, (that's not much even converted to metric!!), hollow braid
(no twisting), 5000 lb breaking strength (that a lot even converted to
metric!!), 25% increase in launch heights. We operate from asphalt and
it seems to be holding up wery well. Expensive? Yes! However in our
environment it promises to far outlast steel which would make it cheaper
in the long run plus the added benifits. Sorry this sounds like a commerical
I was just so tired of that !@#$@#%%^# wire. If anyone else has any experience
with this stuff is there anything we should be looking out for?

Happy Winching,
Craig-



Well, I was waiting for someone from the Memphis club to post. However,
no one has so far, so I'll have a go.

The Memphis club purchased Glen Lawler's winch a few months ago. My
club, Southern Eagles, used this winch with excellent results for a
couple of years. We only stopped using the winch when we moved to an
airport with crossing runways where we had marginal room for the cable.

A couple of weeks ago, Glen Klingshirn and I had the good fortune to be
invited up to Memphis to train their guys on winch launching. Just as an
aside, I have to say that you won't find a better bunch of folks to fly
with. The hospitality and fellowship was superb. They are also making
the ultimate contribution to the future of soaring in the U.S.: The
Memphis Soaring Society has established their own field at Cherry
Valley, Arkansas. They are doing it right with a huge field, immense
hangar and a beautiful clubhouse under construction.

Anyway, the MSS has equipped one drum on the (two drum) winch with
Spectra. The original wire rope is on the other drum. After a few
launches with the cable, we switched to the Spectra and didn't look
back. The Spectra seems to give higher launches although we didn't do
enough launches with the wire to make a valid comparison. The Spectra
had no more noticeable stretch than the cable so we didn't have any
"bungee" dynamics to work around. To me the biggest, and unexpected,
advantage of the Spectra was that it did not have enough mass to throw
itself into a tangle. During training of new winch drivers, we had a few
incidents which would have put a tangle in wire rope, but with the
Spectra, there was never a tangle of any kind. The Spectra also seemed
to be holding up well through 30 launches or so. The only minor problem
with the Spectra is that it has so little mass that the cable end strop
would fall through the chute unless the winch driver got the power back
on quickly after the glider released. This was just a problem with winch
driver trainees and resolved after each driver got more experience.

It may be that exotic stuff like Spectra is not needed for a winch. The
dacron rope that we have used for auto launch is very similar in
appearance and has almost no stretch like the Spectra. It is also
abrasion resistant. It is not as strong as Spectra but is plenty strong
enough. It may do as well as Spectra on a winch and is cheaper.

Wallace (help stamp out winchophobia) Berry

I have flown a K8 from a winch launch several dozen
times and never experienced a 'pitch up' as you describe.
I was trained for winch launching on a Ka-7 and then
was moved into the K8. I loved it! The winch, a Tost
unit, I think, was powered by a General Motors V-8
gasoline engine which was mounted on an ancient Mercedes
truck of maybe 5 ton capacity.

The winch was great for launching the single-seaters.
My best altitude at release height was 700 meters
in the K8. The winch could have used a bit more grunt
for launching the Grob 103, but it still managed to
get to 400 meters or so.

Could the weight and balance been out of limits on
the K8 you were launching?

I wish our club had a winch! Then, I would get to
drive the 'Lepo' again!

Ray Lovinggood
Carrboro, North Carolina, USA
LS-1d, 'W8'

At 12:06 11 August 2003, Chris Reed wrote:
'Andreas Maurer' wrote in message
.. .
On Thu, 7 Aug 2003 07:52:53 -0600, 'Bill Daniels'
wrote:



The boundary on the high side of acceleration is the
tendency of some
gliders with high CG's, low hooks and limited down
elevator authority to
pitch-up uncontrollably when a threshold acceleration
is exceeded.

Please tell me the names of these gliders. I have
NOT heard of a
single one yet that showed this behaviour. Not one.

In my experience the K8 pitch-up was near uncontrollable
when winching. If
you had winched it previously you learnt the theoretically
correct
procedure, which was:

a. Stick back to get the nose skid up.

b. Stick central to run on the main wheel; and then

c. (*Immediately the main wheel left the ground) Knuckles
hard into the
instrument panel and wait for the pitch to become controllable.

On anything but the softest of take-ups (a) and (b)
disappeared, as the
glider was flying before you could react, so the *real*
procedure was stick
full forwards as soon as the glider moved.

Once full pitch control was re-established the rest
of the launch was fine,
but the first two seconds were only semi-controlled,
and that only if you
knew what to expect. I never saw a first flight in
the K8 where the pilot
reacted in time to prevent an uncontrolled pitch-up
as soon as the main
wheel left the ground. And our winch was not any kind
of high-powered
monster.

All the glass gliders I've seen winching behaved well,
but the K8 was ...
interesting.