Collins' Lanyard and Uneven Cutaway Cables?

[20kN 93]

faulknerwn

As to why to not have a Collins Lanyard - there were two incidents about 10 years back which show issues with them. One was a tandem which pulled low - had a good main but the AAD fired. The reserve freebag fell out and down (instead of up like it would on a normal cutaway) and it pulled the Collin's Lanyard which released one main riser only. The instructor cutaway but by this point the reserve had bag-locked and the tandem died. UPT added a staging system on the reserve system after this to ensure that the pilot chute was pulling before the bag would come out.

A second case had a Skydive Chicago student if I remember correctly have an incident. He opened normally at 5500, but some stitching broke causing the rig to stretch on the RSL side. It popped the reserve pilot chute which trailed behind the student for the canopy ride. As the student turned to final (this part was on video) the bag came out and the Collins Lanyard cutaway one riser. The student (low as @(*^@&#) cutaway and that let the skyhook open the reserve in time. It was sketchy!

So manufacturers might have to add staging devices on their reserve containers or design their rigs to make it harder for the reserve to come out accidentally (which also makes it harder to come out when it is on purpose.) Some may not want to do that. I personally am not a fan of a device which can cutaway one riser of my perfectly good main.

Like most inventions - they have good and bad points. Whether the good points outweigh the bad is an individual call. The Collins Lanyard was originally designed for tandem risers that broke, but the only time I have heard of risers breaking in the past 15-20 years was a guy who knew his risers were so junky that he had a brand new pair in his gear bag that he had just been too lazy to put on..

How does the reserve freebag being deployed cause the collins' lanyard to retract? Did the Skyhook yank the RSL/ collins' lanyard out or something? Normally they are separate and unrelated systems.

[pchapman 261]

20kN

How does the reserve freebag being deployed cause the collins' lanyard to retract? Did the Skyhook yank the RSL/ collins' lanyard out or something? Normally they are separate and unrelated systems.

They're not separate and unrelated, but all connected together unless pulled in a particular way to disconnect the MARD.

It's messy without diagrams but until someone has a more elegant description:

The reserve bag falls out, which pulls on the MARD device on the bridle, which stays connected to the RSL because the RSL is supposed to pull on the bag without disconnecting... and thus it stays connected when pulled from the other end. (Assuming the pilot chute didn't grab enough air to disconnect the MARD first.)

That RSL lanyard from the MARD part pulls on the rest of the RSL system, which includes the Collins lanyard. (It's a very very rare situation, but can lead to an unwanted one sided cutaway, while the reserve bag is falling down and possibly spinning around wrapping itself in the bridle.)

One then asks, will the Collins lanyard pull the cutaway cable too much, before the whole RSL system to the main riser is stretched taut? And how is the RSL held in place and with how much resistance, where it goes over the shoulder?

Some rigs have the RSL sitting within a folded channel. UPT has it velcroed down. The Velcro damages stuff around it, but does hold the RSL more tightly in place, especially when pulled in shear (lengthwise instead of peeling).

UPT also have the loop of the Collins lanyard (that goes around the cutaway cable) on a separate 'leg' of the RSL system -- which in effect gives more slack in the system: Pulling the MARD lanyard 6" won't therefore pull the Collins lanyard 6". Originally UPT didn't have that separate leg, but since one of the accidents they changed the design.

[fcajump 153]

gowlerk

In 90s era rigs they are usually hand tacked with super tack, a heavy waxed thread. It is VERY common to need to re-do this. Riggers need to check the condition of this at repack and inspection time without fail. They usually just float the rest of the way. But the left one passes through a channel that should not allow what happened here. There are two types of housing. Extensible and non extensible. (one can not be compressed, the other can not be extended) each has advantages and disadvantages. In order to be flexible they have to do one or the other. This one must have been of the extensible type. When it was stretched out the cable became too short.

Vectors (at least pre-MARD) didn't tack the handle end.

JW

Always remember that some clouds are harder than others...

[gowlerk 1,901]

Quote

Vectors (at least pre-MARD) didn't tack the handle end.

They actually did, but not at the very end. They are tacked under the mudflap with 1 inch of play either direction. The instructions are in this thread. (second post)

http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=4598207

[faulknerwn 36]

Here is a link to the two threads I mentioned as well as a third I had forgotten about:

Tandem Fatality: http://www.dropzone.com/cgi-bin/forum/gforum.cgi?do=post_view_flat;post=3331658;page=1;sb=post_latest_reply;so=ASC;mh=25;

Student Cutaway http://www.dropzone.com/cgi-bin/forum/gforum.cgi?do=post_view_flat;post=4114143;page=1;sb=post_latest_reply;so=ASC;mh=25;

Incident in Poland: http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=4637601;search_string=Collins%20Lanyard%20cutaway;#4637601

[20kN 93]

faulknerwn

Here is a link to the two threads I mentioned as well as a third I had forgotten about:

Tandem Fatality: http://www.dropzone.com/cgi-bin/forum/gforum.cgi?do=post_view_flat;post=3331658;page=1;sb=post_latest_reply;so=ASC;mh=25;

Student Cutaway http://www.dropzone.com/cgi-bin/forum/gforum.cgi?do=post_view_flat;post=4114143;page=1;sb=post_latest_reply;so=ASC;mh=25;

Incident in Poland: http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=4637601;search_string=Collins%20Lanyard%20cutaway;#4637601

So basically the inadvertent cutaway via the collins lanyard could happen anytime the jumper is under a fully inflated main and for whatever reason they deploy the reserve? That makes me think twice about a possible canopy transfer in my bag of tricks should I ever need it. It also brings into question the safety of the general rule of malfunctions under 1000' are treated by deploying your reserve without cutting away.

However, I would think that if you were to deploy your reserve while under canopy the launching of the PC would disconnect the Skyhook regardless of whether the PC inflates or not. That's the intended function.

[SethInMI 145]

20kN

However, I would think that if you were to deploy your reserve while under canopy the launching of the PC would disconnect the Skyhook regardless of whether the PC inflates or not. That's the intended function.

You realize that every time your reserve is used the PC launches, even in an RSL / MARD deployment? The system has to stay connected throughout the initial launch / pull sequence, and so it requires some force to unhook it, the manual says 5-7 lb. So no, the launch of the PC won't necessarily disconnect a Skyhook.

But Vectors should have been retrofitted with a staging loop to make sure that the reserve can't leave the container unless an inflated PC or inflated main is pulling hard on the bridle, so deploying the reserve after the main is deployed will either cause the PC to trail harmlessly behind the jumper, or will cause the reserve to deploy and disconnect the skyhook.

It's flare not flair, brakes not breaks, bridle not bridal, "could NOT care less" not "could care less".

[faulknerwn 36]

Quote

So basically the inadvertent cutaway via the collins lanyard could happen anytime the jumper is under a fully inflated main and for whatever reason they deploy the reserve? That makes me think twice about a possible canopy transfer in my bag of tricks should I ever need it. It also brings into question the safety of the general rule of malfunctions under 1000' are treated by deploying your reserve without cutting away.

Definitely, if you have a skyhook it is something to consider. Vectors have staging loops to help fix this issue, but I don't think (without looking it up) Javelin's with Skyhooks do. And the Javelin closing sequence is quite different than the Vector. I think Aerodyne rigs do have that staging loop.

Also if my memory serves me correctly, although I don't recall seeing a sport vector without the staging loop, that they only became mandatory on tandems after that incident. Certainly, all modern Vectors are set up for it, but there might be some of the early years of the rig with early versions of the skyhook which are not.

[ufk22 32]

Staging loop is not mandatorily on sport vectors. The problem was mostly due to the single line from the skyhook to the Collins cutaway to the rsl loop on the riser.
The reserve/skyhook line could put tension on the Collins disconnect
This was replaced with a y setup where the skyhook line and the Collins disconnect each ran independently from the rsl loop.
Tension from the skyhook line is directed to the rsl loop without tensioning the Collins disconnect.

This is the paradox of skydiving. We do something very dangerous, expose ourselves to a totally unnecesary risk, and then spend our time trying to make it safer.

[gowlerk 1,901]

ufk22

Staging loop is not mandatorily on sport vectors. The problem was mostly due to the single line from the skyhook to the Collins cutaway to the rsl loop on the riser.
The reserve/skyhook line could put tension on the Collins disconnect
This was replaced with a y setup where the skyhook line and the Collins disconnect each ran independently from the rsl loop.
Tension from the skyhook line is directed to the rsl loop without tensioning the Collins disconnect.

Which means that if you are going to attempt a canopy transfer you should not disconnect the RSL first as someone has suggested. The RSL connection is keeping the Collins lanyard from pulling on the yellow cable. Unless you still have the old system. If and when the reserve P/C starts pulling the Skyhook will release.

The confusion is great here.

[20kN 93]

It appears that the Y lanyard does not eliminate this issue. This photo is from a rig with a DOM of 2018 and I was easily able to extract the left side cutaway cable entirely by pulling on the reserve bridle. I tried wearing the rig and I had someone else pull on it. Same result.

Here is a photo: https://www.photobox.co.uk/my/photo/full?photo_id=501577663455

The staging loop does not seem to take much force to remove. It seems to take even less force to remove than the RSL. It seems like a possibly better option would be to just make the Y portion of the RSL lanyard longer so that the freebag cannot weight the collins' lanyard. Why doesent the manufacturer do that instead?

[pchapman 261]

Photo link not working.

And not much force to remove the staging loop? Sorry, I lost your point.

If the pilot chute pulls the bridle at the staging loop, it releases easily as it should (on a normal deployment).
If the RSL/Skyhook system pulls the bridle at the staging loop, it releases easily as it should (on a Skyhook assisted deployment).

Meanwhile the bag is in the container and can't fall out and "back load" the RSL system or pull the Collins lanyard.

Or are you suggesting freebags should be much harder to pull out of the container, with much stronger staging restraints?

(The rigger's seal thread on the Skyhook does a bit of that, when the deployment is started by the pilot chute. Takes some pounds of force to break it.)

-----------
Back to your test:

Were you able to pull the L side cutaway cable far, when pulling the bridle, with the RSL velcro still attached all across the shoulder, when pulling down and back (relative to someone wearing a rig standing up)? That would be the direction the freebag would tumble out in the rare cases where that could happen.

That test seems interesting.

[skytribe 16]

faulknerwn

Also if my memory serves me correctly, although I don't recall seeing a sport vector without the staging loop, that they only became mandatory on tandems after that incident. Certainly, all modern Vectors are set up for it, but there might be some of the early years of the rig with early versions of the skyhook which are not.

Ive had brand new UPT vectors come without a staging loop, upon contacting UPT to find out why. They sent a reply that it was only recommended on tandem and larger canopy containers and hence thats why it was not included. They specifically did not like it being called a hesitator loop.

For UPT, aerodyne - the use of this elastic loop is optional. ( https://www.flyaerodyne.com/...ual052017_online.pdf) Page 25.

As a friend of mine is a rigger at UPT, they told me that they don't pack most container with the staging loop. The wording of the reply from the manufacturer and the actions meant I now don't pack using the staging loop for most sport rigs.

[20kN 93]

skytribe

***
Also if my memory serves me correctly, although I don't recall seeing a sport vector without the staging loop, that they only became mandatory on tandems after that incident. Certainly, all modern Vectors are set up for it, but there might be some of the early years of the rig with early versions of the skyhook which are not.

Ive had brand new UPT vectors come without a staging loop, upon contacting UPT to find out why. They sent a reply that it was only recommended on tandem and larger canopy containers and hence thats why it was not included. They specifically did not like it being called a hesitator loop.

For UPT, aerodyne - the use of this elastic loop is optional. ( https://www.flyaerodyne.com/...ual052017_online.pdf) Page 25.

As a friend of mine is a rigger at UPT, they told me that they don't pack most container with the staging loop. The wording of the reply from the manufacturer and the actions meant I now don't pack using the staging loop for most sport rigs.

What is the reasoning for not using it? It seems like it exposes the user to a pretty serious risk. What happens if they get into a canopy collision down low and deploy the reserve while still under a main? At low speed the RPC may not inflate and then we are in this left-side riser cutaway situation.

[skytribe 16]

I believe some of the original reasoning was contained in the document.

https://aeroclub.at/uploads/download/SM090101.pdf

As stated the likelyhood of this occuring is small and affect tandem and larger containers more so than smaller ones.

This is a copy of the response I got about the staging loop on sport rigs.

http://gemapar.fr/Documents/Materiels/note/NO092.pdf

The current UPT vector 3 manual clearly states its optional as does the aerodyne manual for skyhooks.

[20kN 93]

pchapman

Photo link not working.

And not much force to remove the staging loop? Sorry, I lost your point.

If the pilot chute pulls the bridle at the staging loop, it releases easily as it should (on a normal deployment).
If the RSL/Skyhook system pulls the bridle at the staging loop, it releases easily as it should (on a Skyhook assisted deployment).

Meanwhile the bag is in the container and can't fall out and "back load" the RSL system or pull the Collins lanyard.

Or are you suggesting freebags should be much harder to pull out of the container, with much stronger staging restraints?

(The rigger's seal thread on the Skyhook does a bit of that, when the deployment is started by the pilot chute. Takes some pounds of force to break it.)

-----------
Back to your test:

Were you able to pull the L side cutaway cable far, when pulling the bridle, with the RSL velcro still attached all across the shoulder, when pulling down and back (relative to someone wearing a rig standing up)? That would be the direction the freebag would tumble out in the rare cases where that could happen.

That test seems interesting.

Here is another try:

https://i.imgur.com/MOfm5Gx.jpg

https://i.imgur.com/SFwMnR5.jpg

I did not have much trouble cutting away the left side riser by pulling on the reserve bridle with the Skyhook still attached. This rig had a DOM of 2018 and uses the Y lanyard RSL discussed earlier.

[pchapman 261]

20kN

I did not have much trouble cutting away the left side riser by pulling on the reserve bridle with the Skyhook still attached. This rig had a DOM of 2018 and uses the Y lanyard RSL discussed earlier.

Aha, I see I'm thinking about the Vector III and you're testing on an Icon. One difference is how the RSL is attached over the shoulder: The Vector has velcro over a long distance. (Like 8" or so on a tiny Vector I'm repacking, including the Collins leg.) The Icon just has the RSL in a fold-over channel, with no or minimal velcro? You can clarify on that point.

So yes, you may find it a lot easier to back-load the L side cutaway cable with an Icon than Vector. That's one place the 2 rigs differ, despite Aerodyne having Skyhook tech bought from UPT. (Aerodyne and UPT have dealt with other minor aspects of staging loop rigging slightly differently too.)

I should also note that you are testing the harness without anyone in it, allowing the shoulder to flex. Wearing the rig would reduce that flex. (In the air under canopy it gets messier: Although there's tension on the harness, the shoulder straps can also sit somewhat above the jumper's shoulders.)

Although the flex might not matter that much either way with the the Icon where the RSL pulled free relatively easily.

So far unless I see better evidence, I'll still trust that the split RSL/Collins lanyard, combined with the velcro'd RSL, will do a the job UPT intends it to do, keeping a backloaded Skyhook/RSL/Collins lanyard from pulling out the L cutaway cable. But I'm also somewhat more concerned with Icon's design.

Yet in some cases all the velcro can be detrimental, such as on a Sigma with a baglocked main and collapsed drogue, where the drag may not always pull the RSL completely free. Tradeoffs.


@ skytribe: Thanks for those documents. I had a similar informal statement from UPT from years earlier, but it's nice to have a printed document stating their position, more recently (2016).

[20kN 93]

pchapman

***
I did not have much trouble cutting away the left side riser by pulling on the reserve bridle with the Skyhook still attached. This rig had a DOM of 2018 and uses the Y lanyard RSL discussed earlier.

Aha, I see I'm thinking about the Vector III and you're testing on an Icon. One difference is how the RSL is attached over the shoulder: The Vector has velcro over a long distance. (Like 8" or so on a tiny Vector I'm repacking, including the Collins leg.) The Icon just has the RSL in a fold-over channel, with no or minimal velcro? You can clarify on that point.

So yes, you may find it a lot easier to back-load the L side cutaway cable with an Icon than Vector. That's one place the 2 rigs differ, despite Aerodyne having Skyhook tech bought from UPT. (Aerodyne and UPT have dealt with other minor aspects of staging loop rigging slightly differently too.)

I should also note that you are testing the harness without anyone in it, allowing the shoulder to flex. Wearing the rig would reduce that flex. (In the air under canopy it gets messier: Although there's tension on the harness, the shoulder straps can also sit somewhat above the jumper's shoulders.)

Although the flex might not matter that much either way with the the Icon where the RSL pulled free relatively easily.

So far unless I see better evidence, I'll still trust that the split RSL/Collins lanyard, combined with the velcro'd RSL, will do a the job UPT intends it to do, keeping a backloaded Skyhook/RSL/Collins lanyard from pulling out the L cutaway cable. But I'm also somewhat more concerned with Icon's design.

Yet in some cases all the velcro can be detrimental, such as on a Sigma with a baglocked main and collapsed drogue, where the drag may not always pull the RSL completely free. Tradeoffs.


@ skytribe: Thanks for those documents. I had a similar informal statement from UPT from years earlier, but it's nice to have a printed document stating their position, more recently (2016).

The Icon does not use any Velcro at all. It just folds into a channel and the end of the RSL tucks up into and behind the container material under the risers similar to how Mirage and a few other companies terminates their RSL right before the shackle. I could see how 8" of Velcro would make it hard to pull out the cutaway cable. However, simply making the Y lanyard longer relative to the RSL's total length will do an even better job without the side effects of Velcro. If the Y lanyard was longer, the entire load would be transferred to the RSL shackle instead of the collins' lanyard.

[20kN 93]

Good to hear.