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DJL

Design intent: Why is the pin curved? See post before polling.

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Please only answer if you really do know the answer, as in you were there when it happened, otherwise hit "see results". This isn't a popularity contest.

I've been told #2 but #1 seems to make more sense. Supporting arguments I've read here on dz.com. One is that it's more common for the bridle to be pulled through rather than pushed. It seems to me that it's just as likely for the pushing angle to correspond with a straight pin, as a curved pin. Also, as you see on bob's set up in the CRW forum, his pin is straight. Is this how all pins were with pullout? Did they change to curved when the BOC method came around?

Note: it's a misconception that CRWdog's don't worry about a premature, a negative 3 second deployment will ruin your day.

Edit: Could a moderator move this to Gear and Rigging, please?
"I encourage all awesome dangerous behavior." - Jeffro Fincher

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Wow, good question. I'll keep an eye on this thread to find out the answer.

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Did they change to curved when the BOC method came around?



I've been skydiving for over 25 years, and the pin was curved when the pilot chutes where on the leg strap and belly strap. So, I don't think it's because of the BOC. Now P.C.s had straight pins, but there were three of those on my rig.

Thanks for getting us thinking.
May your trails be crooked, winding, lonesome, dangerous, leading to the most amazing view. May your mountains rise into and above the clouds. - Edward Abbey

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Pull outs have straight pins

Throw outs are curved because the straight back
pull force would hang up and possible not deploy...
and would most likely gouge up the material in the way.

I had a 'pull out' rig with a flat little curved pin...
But it was not 'factory' and though it worked, I had it replaced with a straight pin.










~ If you choke a Smurf, what color does it turn? ~

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Look at the direction the pull force is being applied from. a Pull out you are pulling the pin straight out or inline with the pin. On a throw out the pull force is coming 90 degrees from the pin orientation.
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I beleive it has to do with the bridle length.
On pullouts the handle to pin length is shorter, so when you pull the handle the pin comes out before arm extentsion is complete.
With a throw out, the length from hacky (m/fist) to pin is much longer. The Pc is behind and above the containers as the pin is pulled, so the curve in the pin allows it to come out cleanly.
If the pin were to be straight there would be leverage forces and the pin may not extract, especially if it is pushed all the way to the eye.

But I'm not a rigger and only have been i the sport 12months so I am speaking from a complete novice point of veiw.:)
You are not now, nor will you ever be, good enough to not die in this sport (Sparky)
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To help prevent a pilot chute in tow. The pilot chute and bridal form a right angle to the pin when the pc is launced. The curve allows the pin to slide out with much less pull force.

Since you are pulling the pin manually and in a straight line with the pin on a pull out system, the straight pin works fine there.

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...pull force is coming 90 degrees from the pin orientation.



Yeah, I thought that might be the case. It was a discussion I read in which Bill Booth chimed in about flexible pins that got me thinking about this. After reading that, the "so the pin doesn't get pushed through" statement started to sound like parrot-talk and I saw that a straight pin on a BOC throwout would probably gouge the crap out of the container.

I got PM'd a link to some material by Bill Booth about flex pins: CLICK

Thanks, folks.
"I encourage all awesome dangerous behavior." - Jeffro Fincher

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We're talking about people DYING here, and you're worried about marking up your container? If you live through it I think that would be the least of worries..
If some old guy can do it then obviously it can't be very extreme. Otherwise he'd already be dead.
Bruce McConkey 'I thought we were gonna die, and I couldn't think of anyone

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Please only answer if you really do know the answer, as in you were there when it happened, otherwise hit "see results". This isn't a popularity contest.



I was there when the pin was invented. It was Hank Asciutto and Dennis Trepiner. They were upstairs in Hank's shop, Para Innovators, in Perris, CA. It is curved because when you pull on the pin from any direction, it rolls un on the outside radius of the curve and will rotate out easily. When it roll up there are only 2 points of contact with the loop because the pin shaft is square. Because of the amount of beer and Jack we were consuming that night, it seemed like so much jiperish to me. But about 30 days latter there was the curved pin. Check PPM, it talks about Hank inventing it.
My idea of a fair fight is clubbing baby seals

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We're talking about people DYING here, and you're worried about marking up your container? If you live through it I think that would be the least of worries..



Yeah, and I land on the runway so I don't get grass stains on my jumpsuit. Assuming that you're kidding but just in case, no.
The question was (to rephrase) whether the pin is curved because A) on a BOC throwout the pin is pulled upwards putting a perpendicular force on the pin or B) so that the if the pin is pushed, it won't go through the closing loop.

I always hear people say that it's curved because of the latter and it didn't sound right.
"I encourage all awesome dangerous behavior." - Jeffro Fincher

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We're talking about people DYING here, and you're worried about marking up your container? If you live through it I think that would be the least of worries..



Yeah, and I land on the runway so I don't get grass stains on my jumpsuit. Assuming that you're kidding but just in case, no.
The question was (to rephrase) whether the pin is curved because A) on a BOC throwout the pin is pulled upwards putting a perpendicular force on the pin or B) so that the if the pin is pushed, it won't go through the closing loop.

I always hear people say that it's curved because of the latter and it didn't sound right.


No, I am not kidding.
Neither A or B is correct. My previous post explained why the pin is curved. The loop at the bridle end keeps it from going through the closing loop.
My idea of a fair fight is clubbing baby seals

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Mine was replying skypuppy in reference to if he really thought I was worried about scuffing my gear vs. people DYING.

I did see your post. That's what I was attempting to convey with A) that a straight pin wouldn't work on a throwout because it can only be pulled in one direction, when most of the time it will be be pulled 90 degrees resulting in scraped out grommets or a PC in tow.
"I encourage all awesome dangerous behavior." - Jeffro Fincher

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B) is an argument invented after the fact.

I prefer Hank Asquito's explanation. The last time I jumped with Hank was 3 years ago in California City. Hank was doing video and I was doing a tandem.
Hank is still advancing parachute design. Weekdays, Hank was working at the Lockheed Skunk Works, putting the finishing touches on the ejection seat in their Joint Strike Fighter prototype.
Hint, Lockheed won that fly-off.

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B) is an argument invented after the fact.

I prefer Hank Asquito's explanation. The last time I jumped with Hank was 3 years ago in California City. Hank was doing video and I was doing a tandem.
Hank is still advancing parachute design. Weekdays, Hank was working at the Lockheed Skunk Works, putting the finishing touches on the ejection seat in their Joint Strike Fighter prototype.
Hint, Lockheed won that fly-off.



You are right on B. Last time I jumped with Hank was about 3 weeks ago.
My idea of a fair fight is clubbing baby seals

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