Spectra winching question

On Mon, 20 Jun 2011 18:32:43 -0400, Tony V wrote:

In our case, our insurer (Costello) said it's going to be synthetic rope
or nothing.

Sounds like bildan was quite prescient about insurer sensitivities.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

Hi Bill,
got any pics of the 20" disk?

We use spectra as you know. We just put cg hooks on our club gliders.
Wow what difference from nose hooks. The day we flew was 90' cross and
the gliders now get the same altitude they did on the nose hook with
wind down the runway. Our runway gives about 4,000'. Got 1400' on the
126 with a conservative launch as we were testing the newly installed
hooks. Then got away in light lift for 1/2 or so. Not bad for a $10
launch! Of course in my ship with the wind down the runway I was
consistently getting 1900'. Plenty to soar away with!

We use one of the large chutes from Germany. it weighs a lot and I
wonder if it does cause a lot of drag.

Steve

On 6/20/2011 10:02 AM, Herbert kilian wrote:
Europeans have tens of thousands of winch launches of experience with
Spectra/Dyneema rope on us and as far as I hear they don't see real
advantages (meaning they are switching back to steel). Neither in
life expectancy nor in launch height or ease of splicing are there
significant reasons to abandon steel. In fact, the winch guillotine
has to be modified to cut Spectra, much more difficult than severing a
steel cable.
Unless you are winching from a really nasty surface I'd say that the
steel cable is still overall the best material to go with.

I miss the good old days when - in a crosswind, winching from a narrow runway
bordered by downwind powerlines - anyone with a winch and steel wire could
(and per the literature not rarely did) easily and spectacularly kill the
power in the 'hood. Can plastic do this?

Would Ben Franklin have used plastic rope for his famous kite experiment?

Funnily enough, I *don't* miss the thrill lost when watching plastic fall
harmlessly to the ground (say, after an unplanned 'wire' break) compared to
wondering how well-constructed some home-brew winch's safety cage was while
watching steel rope or single-strand downhole wire lunging toward me. (Yes, I
know I coulda deferred winching until a 'decent winch' became available, but
unfortunately I'm mortal, and I never wanted to discover how fine the line
between disappointed/angry glider pilots and an ugly mob!)

Regards,
Bob - those darned double-edged swords! - W.

On Jun 20, 5:03*pm, Stephen wrote:
Hi Bill,
got any pics of the 20" disk?

We use spectra as you know. We just put cg hooks on our club gliders.
Wow what difference from nose hooks. The day we flew was 90' cross and
the gliders now get the same altitude they did on the nose hook with
wind down the runway. *Our runway gives about 4,000'. Got 1400' on the
126 with a conservative launch as we were testing the newly installed
hooks. Then got away in light lift for 1/2 or so. Not bad for a $10
launch! *Of course in my ship with the wind down the runway I was
consistently getting 1900'. Plenty to soar away with!

We use one of the large chutes from Germany. it weighs a lot and I
wonder if it does cause a lot of drag.

Steve

Steve, you don't need a picture - just take a look at the bottom of a
55 Gal plastic barrel. Cut off the bottom with a sabre saw or box
cutter leaving a 1" - 2" lip for edge reinforcing. The lip goes on
the glider side so it doesn't dig in. While you're at it, stock up on
several disks as they get beat up after a few hundred launches. Used
barrels range from dirt cheap to free. They come in various diameters
so get the biggest one you can find.

Put an I-bolt through the middle of the disk using large fender
washers. Avoid the cheap bent-rod I-bolts and get the forged ones.
Use an I-nut(?) so there are rings on both sides of the disk. Put the
weak link on the glider side of the disk so the disk pulls away toward
the winch if the link breaks.

If you want to look really cool, match the color of the disk to the
weak link so everyone can see the right link is being used.

This isn't specific to disks but I don't like to see anyone in front
of a glider after it is connected to the winch. To do this put a ring
for the Tost ring and hook quick connect on the winch end of the winch
rope - or vice versa if you prefer, it isn't important. This way the
safety rope with disk can be attached to the glider CG hook as it is
being prepared for launch. Pull the disk and safety rope to the side
beyond the wing tip. The winch rope is attached to the disk and
safety rope only when the pilot signals he is ready to launch. This
procedure keeps the ground crew out of harms way while hooking up a
rope.

On Jun 20, 9:11*pm, bildan wrote:
On Jun 20, 5:03*pm, Stephen wrote:





Hi Bill,
got any pics of the 20" disk?

We use spectra as you know. We just put cg hooks on our club gliders.
Wow what difference from nose hooks. The day we flew was 90' cross and
the gliders now get the same altitude they did on the nose hook with
wind down the runway. *Our runway gives about 4,000'. Got 1400' on the
126 with a conservative launch as we were testing the newly installed
hooks. Then got away in light lift for 1/2 or so. Not bad for a $10
launch! *Of course in my ship with the wind down the runway I was
consistently getting 1900'. Plenty to soar away with!

We use one of the large chutes from Germany. it weighs a lot and I
wonder if it does cause a lot of drag.

Steve

Steve, you don't need a picture - just take a look at the bottom of a
55 Gal plastic barrel. *Cut off the bottom with a sabre saw or box
cutter leaving a 1" - 2" lip for edge reinforcing. *The lip goes on
the glider side so it doesn't dig in. *While you're at it, stock up on
several disks as they get beat up after a few hundred launches. *Used
barrels range from dirt cheap to free. *They come in various diameters
so get the biggest one you can find.

Put an I-bolt through the middle of the disk using large fender
washers. *Avoid the cheap bent-rod I-bolts and get the forged ones.
Use an I-nut(?) so there are rings on both sides of the disk. *Put the
weak link on the glider side of the disk so the disk pulls away toward
the winch if the link breaks.

If you want to look really cool, match the color of the disk to the
weak link so everyone can see the right link is being used.

This isn't specific to disks but I don't like to see anyone in front
of a glider after it is connected to the winch. *To do this put a ring
for the Tost ring and hook quick connect on the winch end of the winch
rope - or vice versa if you prefer, it isn't important. *This way the
safety rope with disk can be attached to the glider CG hook as it is
being prepared for launch. *Pull the disk and safety rope to the side
beyond the wing tip. *The winch rope is attached to the disk and
safety rope only when the pilot signals he is ready to launch. *This
procedure keeps the ground crew out of harms way while hooking up a
rope.- Hide quoted text -

- Show quoted text -

Bill,
Sorry to divert, but where are you operating?