How reliably do CG hooks disconnect when the angle of the ropeexceeds the autorelease angle

Originally Posted by Dan Marotta

I was taught that, if unable to release, the glider should circle the
winch rather than slingshot towards the ground.Â* And why wouldn't the
driver cut the cable as soon as the glider overflew the winch and
started down?Â* Training...

On 6/8/2020 5:59 PM, Ventus_a wrote:
he winch driver didn't cut the cable and the winch was getting
destabilised as the glider went through about 45 degress down towards
the ground behind the winch. Going through about 400' with lots of
frantic pulling on the release and the stick the cable finally let go
and the day was saved.. Some badly shaken people and the hook
installation got a good working over to ensure that it couldn't happen
again

Colin

--
Dan, 5J

Hi Dan

The winch driver was an older gentleman and he bailed out of the winch. I suspect lack of familiarity with the cutting system and a sense of his own vulnerability prevailed. Since then a more robust training system is in place for winch drivers

Us older guys need to step up our game!

On 6/9/2020 4:45 PM, Ventus_a wrote:
Dan Marotta;1022870 Wrote:
I was taught that, if unable to release, the glider should circle the
winch rather than slingshot towards the ground.Â* And why wouldn't the
driver cut the cable as soon as the glider overflew the winch and
started down?Â* Training...

On 6/8/2020 5:59 PM, Ventus_a wrote:-
he winch driver didn't cut the cable and the winch was getting
destabilised as the glider went through about 45 degress down towards
the ground behind the winch. Going through about 400' with lots of
frantic pulling on the release and the stick the cable finally let go
and the day was saved.. Some badly shaken people and the hook
installation got a good working over to ensure that it couldn't happen
again

Colin-

--
Dan, 5J
Hi Dan

The winch driver was an older gentleman and he bailed out of the winch.
I suspect lack of familiarity with the cutting system and a sense of his
own vulnerability prevailed. Since then a more robust training system
is in place for winch drivers





--
Dan, 5J

Does anyone have experience with non-Tost rings failing to release in Tost releases?

I've been warned about this possibility, and I know how to verify that a ring is genuine Tost. The explanation that I've been given is that 'hardware store rings' change shape with use and that at some point the elongation prevents the release.

On Monday, June 8, 2020 at 8:33:23 AM UTC-4, son_of_flubber wrote:
Does anyone have experience with non-Tost rings failing to release in Tost releases?

I've been warned about this possibility, and I know how to verify that a ring is genuine Tost. The explanation that I've been given is that 'hardware store rings' change shape with use and that at some point the elongation prevents the release.

That is correct - there is a good chance that a hardware store ring or a chain link can deform and kind of swage itself onto the beak inside the Tost hook, making it very difficult to release. That subject was discussed in great length in the 'winchdesign' forum.

Uli
'AS'

Also note that the small hookup ring can wear. If it gets deformed or reduced in size, it can jam or prematurely release. I looked for the specification on minimum thickness, but couldn't find it with a (very brief) search. Check with Wings & Wheels to see if they know the correct "go-no go" dimension.

On Monday, June 8, 2020 at 9:38:29 AM UTC-4, wrote:
Also note that the small hookup ring can wear. If it gets deformed or reduced in size, it can jam or prematurely release. I looked for the specification on minimum thickness, but couldn't find it with a (very brief) search. Check with Wings & Wheels to see if they know the correct "go-no go" dimension.

Mark - according the the DIN-LN65091, the oval ring has a wire diameter of 8mm, +0, -0.3mm. The round ring has a wire diameter of 7mm, +0, -0.3mm. The O.D. of the round ring is 35mm, +-0.3mm, which would give it a nominal I.D.. of 21mm. If you do a quick tolerance stack-up using just min.-max. material conditions while neglecting any ovality, the I.D. could range from 21.9mm to 20.7mm
The material specifications call for a high carbon Chrome-Vanadium alloy. No welding is permitted.

Uli
'AS'

On Monday, June 8, 2020 at 11:16:32 AM UTC-6, AS wrote:
On Monday, June 8, 2020 at 9:38:29 AM UTC-4, wrote:
Also note that the small hookup ring can wear. If it gets deformed or reduced in size, it can jam or prematurely release. I looked for the specification on minimum thickness, but couldn't find it with a (very brief) search. Check with Wings & Wheels to see if they know the correct "go-no go" dimension.

Mark - according the the DIN-LN65091, the oval ring has a wire diameter of 8mm, +0, -0.3mm. The round ring has a wire diameter of 7mm, +0, -0.3mm. The O.D. of the round ring is 35mm, +-0.3mm, which would give it a nominal I..D. of 21mm. If you do a quick tolerance stack-up using just min.-max. material conditions while neglecting any ovality, the I.D. could range from 21.9mm to 20.7mm
The material specifications call for a high carbon Chrome-Vanadium alloy. No welding is permitted.

Uli
'AS'

Thanks!

Soooo....."no welding allowed"......how do they make the ring? Just asking......usually round "wire/rod", bent, welded together.....
Shrug....

On Monday, June 8, 2020 at 1:16:32 PM UTC-4, AS wrote:
...according the the DIN-LN65091, the oval ring has a wire diameter of 8mm, +0, -0.3mm. The round ring has a wire diameter of 7mm, +0, -0.3mm. The O.D. of the round ring is 35mm, +-0.3mm, which would give it a nominal I.D. of 21mm. If you do a quick tolerance stack-up using just min.-max. material conditions while neglecting any ovality, the I.D. could range from 21.9mm to 20.7mm

For those of us who know how to use a pair of calipers, and not much else, what is a quick way to determine that a ring is worn out?