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AndyMan

Skyhook collins question

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Unfortuantely UPT closes early on Fridays, so I couldn't get them directly.

Riggers:

Quick question - during a table-test of a Vector with Skyhook, the collins lanyard completely pulled the cuttaway on the left riser before the seal thread on the skyhook broke. The right riser did not release. Is this common?

Seems like it could make a low accidental reserve release a bit more interesting than normal.

_Am
__

You put the fun in "funnel" - craichead.

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Unfortuantely UPT closes early on Fridays, so I couldn't get them directly.

Riggers:

Quick question - during a table-test of a Vector with Skyhook, the collins lanyard completely pulled the cuttaway on the left riser before the seal thread on the skyhook broke. The right riser did not release. Is this common?

Seems like it could make a low accidental reserve release a bit more interesting than normal.

_Am



What sort of test?

The Collins cannot release the right riser. The Collins stuff only affects the left riser.

If you were just pulling on RSL (pulling on the disconnected shackle?) then there is no expectation that the right side will release.

It is the release of the right side by pulling the cutaway handle that usually accounts for the force pulling on the RSL, so the expectation is that the right riser has already released.

So, how were you doing your test? And what had you expected to happen?

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I was pulling on the pilot chute. I was expecting the skyhook to release the RSL, and the bag to come from the container as if during a normal terminal reserve opening.

I observed the single pass of seal thread holding the RSL and skyhook together. Then the skyhook pulled the RSL, the RSL pulled the collins which in turn released the left side cuttaway. The seal thread did not release on the RSL until after the left side cuttaway had already disconnected.

I suspect this is an indicator the left yellow cable is too short, but wanted some opinions.

A real life scenario would be during an accidental reserve activation with the main already deployed, the pull on the pilot chute could cause the left side to cuttaway - similar to the accident at Skydive Chicago a few monthes back, but without the rig damage.

_Am
__

You put the fun in "funnel" - craichead.

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I suspect this is an indicator the left yellow cable is too short, but wanted some opinions.



Measure the yellow cutaway cable coming out of the hard housing (riser side) They should be:

Type.............Right (short side).......Left (long side)
RSL-Sport...............7 ½”.....................5 ½”

This info is located on PG 81 of the V3 manual http://www.unitedparachutetechnologies.com/PDF/Support/Manual/MAN_004___Vector_3_Manual_07_44_13[1].pdf


ETA: Also, remember that the skyhook is going to be loaded way faster than walking it across the ground, which could cause the seal thread to break faster (jerk vs constant slow force)
"I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly
DPH -7, TDS 578, Muff 5153, SCR 14890
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This was not a "malfunction". In a real life situation, the deploying reserve pilot chute should not release the left riser. Depending on your velocity at release, the reserve pilot chute would either "tow"' or deploy the reserve. If your forward velocity at release is over 20 miles per hour, the red thread should break, and your reserve will probably deploy "normally". If your velocity is below 20 mph, you may tow the pilot chute, either because the red thread does not break or because there is not enough force to pull the reserve bag out of the container. The latter can occur on most containers, and has nothing to do with the Skyhook or Collins' Lanyard.

If it tows, you have three choices: 1. Cutaway, and let your reserve deploy. 2. Pull the pilot chute back in, being very careful not to disturb the Collins' Lanyard, or 3. Keep your mains velocity as slow as possible, by either not releasing your brakes, or if already released, pull them half way down and make slow turns to landing. I had to do this once when a tandem student reached back and pulled the reserve ripcord after the main was open. Most sport mains under 200 square feet will be going over 20, so you only have to worry about towing a pilot chute on large student or tandem mains.

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If your forward velocity at release is over 20 miles per hour, the red thread should break, and your reserve will probably deploy "normally". .



how probable???
You are not now, nor will you ever be, good enough to not die in this sport (Sparky)
My Life ROCKS!
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That's why I put normally in italics...it's a crap shoot. Two outs always are. That's the dirty little secret about AAD's. Since their widespread acceptance, the number of two-outs has skyrocketed. However, two-outs rarely result in death or serious injury, and no pulls always do (without an AAD). Knowing that, I jump with an AAD. But I also realize that I had better be ready to handle all those extra little problems an AAD might present me with. However, The one AAD problem I'm not prepared to handle, is a half cut through loop that makes it impossible to open my reserve by pulling the ripcord.

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Shouldn't the split at the end of the collins lanyard, the long velcro attachment and the shackle attached to the right riser prevent a reserve pilot chute from detaching the left riser?

The reserve pilot chute must pull a lot of other stuff out before it starts pulling on the left cutaway cable. If not, maybe the split should be a lot longer.

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If your forward velocity at release is over 20 miles per hour, the red thread should break, and your reserve will probably deploy "normally". .



how probable???



I did a bunch of test jumps to test how much the thread holds the pc in the event of a total. I did double passes, triple passes, I even used harness thread. Most of these jumps were out of a porter where we asked the pilot to slow the speed down as much as possible. Every one of these jumps, even the harness thread jump resulted in no hesitation. Myself Im not concerned about the seal thread breaking, we tried very hard to cause hesitation and never had it. Could we have made it happen, yes, but not under normal circumstances and packing. Granted these were faster than 20 mph, but who falls at 20 mph? I even used a 3rd canopy with the cutaways on the risers to get a slow as possible reserve deployment, and from the time it took me to cutaway the 3rd canopy and pull my silver I was fast enough to not cause a hesitation. Bill wanted honest tests with many variables, in real life situations and we came up with them and tried them. I even support the idea that they should allow two passes of seal thread on your pack job to increase the chance that your freebag will stay with your main after cutaway.


Ray
Small and fast what every girl dreams of!

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but who falls at 20 mph?



People under a fully inflated and flying main canopy.

I can tell by your post that the light bulb has not come on yet, hopefully my cryptic response will help.
________________________________________
I have proof-read this post 500 times, but I guarantee you'll still manage to find a flaw.

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Were the main risers loaded with body weight during the "table test"?

Perhaps the extra friction at the left side 3 ring loop when the risers are loaded, and the resulting increased friction inside the cutaway cable housings would then require more force to achieve left side riser release than would be available through the backloading of the collins lanyard by the red thread-attached skyhook/PC which you described.

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