Statistical approach to PC in tow cutaway decision

[ChrisD 0]

Heck dude, in the crossbow and piggyback days the spring loaded PC would hurt sometimes as it hit your head, whatever, the thing was bouncing around in the burble so much!
C

Lookin over your shoulder was sop not an ep!

But what do I know, "I only have one tandem jump."

[chuckakers 370]

Or......

it could entangle with the reserve and leave you powerless to manipulate it since your risers are no longer within your reach.


Hmmmmm.

Chuck Akers
D-10855
Houston, TX

[BrianM 1]

chuckakers

Or......

it could entangle with the reserve and leave you powerless to manipulate it since your risers are no longer within your reach.


Hmmmmm.

It could do worse than that. I had a PCIT last year. I did not cut away. I ended up with a main-reserve entanglement in which the reserve never left the freebag. I landed the fully open and perfectly flying main. I am very happy I did not cut away.

Unrelated, but it was a night jump, I landed in the middle of a forest with my freebag between my knees and my reserve PC in my teeth. My only injury: walking out behind the guys who found me, a branch snapped back and struck my eye, giving me a corneal abrasion.

We recovered the gear the next day and found the main PC was folded in half (hacky was near the base) and the bridle was wrapped and knotted around the whole thing.

"It's amazing what you can learn while you're not talking." - Skydivesg

[unkulunkulu 0]

Ok, I will bump this thread. I have been searching extensively and couldn't find the exact information. So I ask for links (preferably) to incident reports where cutting away in a PCIT situation clearly lead to an undesirable outcome.

[pchapman 261]

I just have one I know of offhand, but there isn't much published about it.

Charles Sheppard, Trenton Ontario Canada, Oct 2005. It was a military jump but a civilian type jump with civilian gear. Reportedly the pilot chute entangled in its bridle so it was a PCIT. Cutaway, reserve pull, main risers entangled with the reserve bridle. I don't know what really happened but that's the way it was presented to me. The idea was that the main problem was not some general entanglement of main and reserve, but specifically cut-away main risers preventing reserve depolyment.

Rig was supposed to be a Talon of some sort, I'd guess something of Talon 2 vintage. The rig vintage would have some bearing on how well the released risers stayed in place, but nothing suggests the gear was particularly old-fashioned in its riser protection. So it is a bit mysterious what actually happened.

The incident is in skydivingfatalities but without useful details http://www.skydivingfatalities.info/search.asp?name=Charles%20Sheppard&Personal=on

[JohnMitchell 14]

tkhayes

How about you check you gear, and then you never have a PC in tow? It is probably the least common malfunction, and certainly ranks up there in prevent-ability.

Completely preventable? Some PCIT's are caused by packing errors invisible to a gear check, such as PC/bridle knotting. Pin-piercing-the-bridle was one that was unthought of until it happened, but that routing of the bridle is still considered "okay" by many.

I do agree with your sentiments that gear choice, checks and maintenance prevent most problems.

[unkulunkulu 0]

Thank you for this information. But the thing is, an experienced instructor in our community who advocates always cutting away in PCIT says just that: there are no clear cut cases where cutting away lead to trouble with modern equipment and call those who say otherwise "theorists", i.e. that arguments don't apply to reality. In discussions here on DZ.com I blindly trusted those statements that cutting away can as well lead to big trouble, but it looks like there are a bunch of incident reports where not cutting away was clearly bad, but no examples of the opposite.

See, I just don't possess any information on the topic, but I want to find out as much as possible, and incident reports are unfortunate but as a source are kind of on the objective side.

[Bertt 0]

There are also two psychological factors to consider. Would you cut away a bag lock? Are you absolutely sure you could tell the difference between a bag lock and a pcit ?
The other thing to consider is that if your plan is to cutaway in some situations and just pull reserve in others, you have to make a decision. In an emergency, your sense of time and your altitude awareness are inaccurate at best. You might take too long to make the decision, and that is usually a killer.
These are the reasons FJC students are usually taught to cutaway and pull reserve for a PCIT. That gves them one course of action that will probably work if they pull the main handle and don't get a canopy over their head.

You don't have to outrun the bear.

[unkulunkulu 0]

While your post makes some points I can agree with, this discussion is on a different topic. I'm interested in facts here, not aspects of performance.

[unkulunkulu 0]

bump! Any links?
Again: not cutting away: plenty of incident reports. Cutting away-> no clear cut incident reports.
But many people here see cutting away as a more dangerous decision.

[Andy9o8 0]

unkulunkulu

it looks like there are a bunch of incident reports where not cutting away was clearly bad, but no examples of the opposite.

The 10/21/13 fatality in Norway might turn out to be an example of the opposite being at least 1 factor.

[BrianM 1]

unkulunkulu

bump! Any links?
Again: not cutting away: plenty of incident reports. Cutting away-> no clear cut incident reports.
But many people here see cutting away as a more dangerous decision.

Did you see my post above (http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=4494932#4494932)?

It's not quite the "cutting away -> incident report" example you are looking for, but it probably would have been if I had cut away (the reserve didn't make it out of the freebag, I landed the main).

"It's amazing what you can learn while you're not talking." - Skydivesg

[pchapman 261]

unkulunkulu

bump! Any links?
Again: not cutting away: plenty of incident reports. Cutting away-> no clear cut incident reports.

Here are a few I dug up, FWIW:

-- One case in the category of "cutting away turns bad":
http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=304748 Someone cut away a PC in tow, main comes out, released riser snagged reserve lines, downplane, but jumper luckily got out of it before landing

-- One more "cutting away turns bad":
In 2003, Diver Driver mentioned a friend's mal where a cut away riser snagged the reserve slider but luckily didn't kill him:
http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=584062#584062
[One more edit:]
In another thread he goes into more detail about what probably was the same case (but not for sure), about "Frank at SDC". The reserve was inflating and collapsing, and he landed during one of the better cycles, and was 'only' seriously injured.
http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=448058#448058



-- In the category of "cutting away would have been bad (but only due to the special and rare circumstance of reserve problems)":
In 2003 Wendy Faulkner related an incident where a friend had a reserve blow up, and then got his main out after all, which he had conveniently not cut away.
http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=586197#586197

[Edit to add this one:]
-- One in the category of "cutting away turns bad":
Mike McGowan, well known videographer, had a cut away riser pull the reserve slider to the top of the lines. He hit trees that luckily snagged the canopy, so it wasn't a fatality. Quite a few years ago now.


-- One that could go either way IMO, but was reported as "cutting away is good":
The girl in Tunisia in 2005 (http://www.dropzone.com/fatalities/Detailed/85.shtml)
She didn't cutaway and had a fatal main/reserve entanglement. In skydivingfatalities.info, it is suggested that not cutting away caused the problem. But the description makes it sound like the entanglement could as well have happened whether the main had been released or not -- The main and free bags entangled along with their bridles, and neither canopy was out of the bag, so I'm not sure the risers got loaded much at all, making it less relevant whether the 3-rings were released. It is a debatable case but I'm not sure the evidence favors either emergency procedure.

[unkulunkulu 0]

Thanks! That's what I'm looking for. If someone else knows more, please don't be silent, we need facts.

[labrys 0]

Quote

If someone else knows more, please don't be silent, we need facts.

You're *never* going to get enough data and *we* as a collective don't necessarily feel the same way that you do. If you manage to collect 25 empirical cases where cutting away caused a problem and 15 where not cutting away caused a problem, it won't mean anything unless you know how many times cutting away turned out to be the right thing to do and how many times not cutting away turned out to be the right thing to do.

Did cutting away work out well a 1000 times and badly 25 times versus not cutting away working out well 3 times and badly 15 times?

You're not going to get enough data. Just make a decision and stick with it. I've seen what the ground looks like at terminal velocity sub 1000' and I'll opt for not taking the time to cut away and getting a canopy open as fast as possible in this situation. The earth gets really big, really fast.

Owned by Remi #?

[unkulunkulu 0]

I kind of got that, it was my first post's intention to evaluate some kind of statistic. I gave up on that. Again: some people argue that cutting away is worth the time and will not lead to entanglements. Now I'm not looking for statistics, I'm looking only for information that can disprove that.

[councilman24 36]

If I had cutaway from a PC in tow I would be dead. As it was the reserve wasn't fully open when I hit the trees.

In another fatality I investigated the only handle pulled was the cutaway handle. I believe (no proof) that the low time jumper lost altitude awareness, reverted to "one procedure", cutaway and didn't have time to pull reserve. (no AAD)

Also consider why cutaway what may be your last good canopy if your reserve malfunctions?

If someone can't learn two procedures, make the decision ON THE GROUND how they are going to REACT to a given situation and do the appropriate procedure as a REACTION, not a decision, then by all means use one procedure.

With a PCIT it's time to stop the skydive by pulling the reserve. Then deal with the consequences.

No one can PROVE anything. I know my decisions and they worked. Make your own, decide on the GROUND and then implement.

I'm old for my age.
Terry Urban
D-8631
FAA DPRE