0
JohnRich

Are all malfunctions human error?

Recommended Posts

Please vote in the above poll to settle another disagreement.

Someone contends that all parachute malfunctions are due to human error. Either we didn't pack correctly, or our body position was incorrect, or our maintenance was poor, and so on. In fact, even our choice to use elliptical high-performance canopies which may be subject to a higher malfunction rate, is a human error, and never the parachute's fault. It was our choice to jump these kinds of canopies and accept the extra risk that is responsible for the malfunctions.

While I agree that many malfunctions are indeed due to human error, I, on the other hand, also think that there are many malfunctions that just happen through no fault of our own. Sometimes the physics of throwing out that much nylon and line at 120 mph, encounters some anomalies, and there's really nothing we can do about that. "Shit happens" is the common expression for this idea. I accept the fact that sometimes things will go wrong, no matter how meticulous I am with my canopy selection, packing, maintenance and deployment.

Lets take the common line-twists as an example. Are they always caused by a tilted body position, improper bag placement, uneven tension on locking stow bands, or bad design which has the stow bands on the far ends of the bag? Yes, sometimes they are. But can all of them be explained this way? Or maybe sometimes, the bag will just hit the air funny and spin, even though everything has been done perfectly?

Which school of thought do you agree with?

Share this post


Link to post
Share on other sites
Quote


While I agree that many malfunctions are indeed due to human error, I, on the other hand, also think that there are many malfunctions that just happen through no fault of our own. Sometimes the physics of throwing out that much nylon and line at 120 mph, encounters some anomalies, and there's really nothing we can do about that. "Shit happens" is the common expression for this idea. I accept the fact that sometimes things will go wrong, no matter how meticulous I am with my canopy selection, packing, maintenance and deployment.



Exactly correct.
People who believe a parachute is so perfectly designed that there must be
someone to blame for every malfunction, are not living in the real world.

- No two pack jobs will ever get every square inch of fabric and every
inch of line into exactly the same position, no matter how hard you try.

- Likewise, no two parachute openings will ever experience exactly
the same turbulent air flows around the canopy during inflation.

A parachute opening is a study in chaos theory, or to put it another way: Events Occur
"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

Share this post


Link to post
Share on other sites
Think about partial inversions on a round. Less sensitive to some of the supposed causes of HP ram air malfunctions. But it happens. Skirt gets blown between lines during opening rebound. Anti inversion netting just about eliminated them. They just malfunctioned by the luck of the draw during opening, IMHO.

No reason the same kind of thing doesn't exist in ram airs. I have percieved a get decrease in tension knots since microline became standard. I believe that the slicker micro line just doesn't knot as easy as dacron. Were these cause by human error? I don't think so. Sometime the slider knoted them up and most of the time it didn't.

IF you believe they all could be prevented if we were perfect in packing, etc. then they STILL would happen because we can't be perfect.
I'm old for my age.
Terry Urban
D-8631
FAA DPRE

Share this post


Link to post
Share on other sites
Quote

If you really wanted to go nuts about it, because a parachute system is designed by humans, any error or malfunction could be blamed on human error. ;)



Took the words out of my mouth.

On the other hand, who cares?

/End thread.
"Dream as you'll live forever, live as you'll die today." James Dean

Share this post


Link to post
Share on other sites
Quote

On the other hand, who cares?



I think it matters to paid packers who automatically get blamed for every malfunction.
It also helps for newer jumpers to understand that careful packing is important, but it's not a guarantee. Packing carefully does help avoid malfunctions, but having a malfunction does not always mean there was a packing error.

Share this post


Link to post
Share on other sites
Quote

But design revisions have largely eliminated both of those mals. What would skydiving be like if riggers had simply said "oh well, shit happens"?



That's not what he was saying or implying.
And sometimes shit does simply happen.

Share this post


Link to post
Share on other sites
Quote

Quote

And sometimes shit does simply happen.



But that shit simply stopped happening because someone thought about how and why that shit was happening and did something about it.



Which is a good thing, of course. And design improvements should and will continue, and I look forward to them. But at the same time, I'm not expecting that a completely malfunction-free canopy or parachute system will be developed any time soon. Because .... well, you know...

Share this post


Link to post
Share on other sites
Quote

But that shit simply stopped happening because someone thought about how and why that shit was happening and did something about it.

I'm not sure that knowledge that hasn't been developed yet would count as error.

Wendy P.
There is nothing more dangerous than breaking a basic safety rule and getting away with it. It removes fear of the consequences and builds false confidence. (tbrown)

Share this post


Link to post
Share on other sites
Quote

I have percieved a get decrease in tension knots since microline became standard. I believe that the slicker micro line just doesn't knot as easy as dacron. Were these cause by human error? I don't think so. Sometime the slider knoted them up and most of the time it didn't.



You just jogged a memory!
Somewhere in the past, Bill Booth made a posting here about correlating malfunctions with number of jumps on a line set.

(Now I'm going from memory here, so don't take this as gospel until someone finds it, or Bill steps up and confirms the numbers)

IIRC, it was something like: tandem canopies with over 300 jumps on a line set have twice the malfunction rate of those with less than 300 jumps on the line set.

And keep in mind he was talking about the Dacron sets on tandems.
I suspect the principles would be the same, but the numbers different, for different materials.

Edit to add: I just found a post where I brought this up and BIll followed my post with a confirmation.
It is around the middle of this page:

http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=1673240;search_string= lines malfunctions;#1673240
"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

Share this post


Link to post
Share on other sites
Quote

Quote

And sometimes shit does simply happen.



But that shit simply stopped happening because someone thought about how and why that shit was happening and did something about it.



There is a very interesting posting Bill Booth once made about designing gear for safety, versus what skydivers will buy.
This is a must read.
(Bill wasn't into paragraph breaks back then, so I have added them here for ease of reading.)

Quote

If I've learned one thing in my 35 years in the sport, it's that it is very
difficult to get most skydivers interested in safety. Years ago, when it became
obvious that my hand deploy pilot chute and 3-ring release made it possible to
deploy a malfunction, and then breakaway from it, 500 feet faster than the
existing internal pilot chutes and Capewell canopy releases allowed, a lot of
jumpers simply started deploying their mains 500 feet lower. Utterly negating
the increase in safety these systems offered. Even today, most jumpers think
that because all gear has a TSO tag on it, one piece of gear is as safe as
another. Unfortunately, that is not true, and most jumpers will choose "fashion"
over safety every time. Here are just a few examples of what I mean, starting
in the '60's, right up to the present day.

(1.) The army found out that if you put 2 foot band of fine netting around the
skirt of a round parachute, you eliminate the most common deployment
malfunction, the partial inversion. The trick worked so well that airborne
troop static line malfunctions went from 1 in 250 to 1 in 250,000. WOW! So, a
company that made round sport reserves (there were no square reserves yet) came
out with an "anti-inversion netted" reserve. NO ONE bought it. You know why, of
course...It packed up 10% bigger. Jumpers past up a proven 1,000 times increase
in safety for smaller pack volume.

(2.) Believe it or not, there is a similar, thought not nearly as drastic,
choice jumpers are making when they buy a square reserve today. Let me explain.
The first square canopies came without sliders, so they had to be built tough.
This meant, among other things, that there was tape running spanwise (from right
to left) between the line attachment points. With the advent of the slider and
softer opening canopies, some companies began leaving the spanwise reinforcing
tapes out of their square reserves. Why? Because they cost less to build, and
(you guessed it) they packed smaller. This proved to be a wise choice, (at
least in the marketing department) because although jumpers very often choose
their mains for performance and durability, the almost always always choose
their reserves base only on price and pack volume. While reserves without
spandwise tapes are fine in most situations, as we have seen recently, they
tend to fall apart when skydivers push the envelope. (ie. big people on tiny
canopies, going head down at high altitudes.) Safety doesn't seem to be any
larger a consideration than it was when they passed up anti-inversion netted
round reserves in the '60's.

(3.) Standard size (large) 3-ring release systems have never given a solo jumper
any problem. They ALWAYS release easily and NEVER break. However, mini 3-rings
look neater, so that's all people will buy. No matter all the reports of hard or
impossible breakaways or broken risers. Don't get me wrong, Properly made, and
maintained, mini 3-ring release systems will handle anything even the newest ZP
canopy with microlines can dish out. Unfortunately, because they are now being
pushed right to their design limit, they must be made EXACTLY right. And a lot
of manufacturers either can't or won't. On the other hand, a large 3-ring system
has so much mechanical advantage, that even a poorly made system will still work
just fine. But then fashion is much more important than safety, isn't it?

(4.) Spectra (or micro-line) is strong and tiny, so it reduces both pack volume
and drag , which means you get a smaller rig and a faster canopy. Unfortunately,
It has a couple of "design characteristics" (this is manufacturer talk for
"problems")

It is very slippery (less friction to slow the slider), and stretches less than
stainless steel. This is why it hurt people and broke so many mini risers when
it was first introduced. Now, I must say that the canopy manufacturers did a
wonderful job handling these "characteristics" by designing new canopies that
opened much slower than their predecessors. However, the fact still remains,
that if you do have a rare fast opening on a microlined canopy, Spectra (or
Vectran) will transmit that force to you (and your rig) much, much faster,
resulting in an opening shock up to 300% higher than if you have Dacron lines.
(It's sort of like doing a bungee jump with a stainless steel cable. At
the bottom of your fall, your body applies the same force to the steel cable as
it would to a rubber bungee cord, but because steel doesn't stretch, your legs
tears off.)

So why would I have a fast opening? Well for one thing, you, or your packer
might forget to "uncollapse" your collapsible slider. BAM! Or perhaps you're
zipping along head down at 160 mph with a rig that wasn't designed for it, and
you experience an accidental container opening. BAM again.

The point is this: If you want to push the envelope, and get all the enjoyment
this sport has to offer, and do it "safely", you need to make careful choices
in the gear you jump. If you weigh 200 lbs. and do a lot of head down, perhaps
you really shouldn't be using a reserve without spanwise reinforcement, mini
3-rings, or a canopy with micro lines. No matter how much you weigh, you should
educate yourself about gear, and then only jump gear that is designed for how
you jump.

So many fatalities occur because of decisions jumpers make BEFORE even getting
in the airplane. Don't join that group. Be smarter than that. Fashion, at least
in skydiving, can get you killed.

Bill Booth


http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=122495;search_string= lines malfunctions;#122495
"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

Share this post


Link to post
Share on other sites
I don't veiw it much different than anything else. When I was young and took hunters safety the instructor often would talk about how in hunting there is no such thing as a true "accident". How every accident is someones fault in some way. If someone gets shot it's someones fault. Either you were carrying a firearm with the safety off, weren't sure of your target AND what is beyond/around it, if you have a misfire it's from a poorly mantained firearm or poor design. So technically yes every malfunction is ultimately a human error whether it's one in manufacture of equipment or poor maintenance, etc.

Share this post


Link to post
Share on other sites

This is a waste of time, but I'll play.
Let's say that somebody throws a flower pot out of a highrise building. You're walking along the sidewalk below and it lands on your head. Bad Luck? Yep, I'd say so, and for you, it happened for no reason.
Looking at the bigger picture, it's obvious that it happened for the reason that somebody threw it out the window. Just because YOU don't know what happened, does not mean that this thing just materialized out of thin air.
It all depends on your point of view. So back to parachute malfunctions. There is a reason for everything, as shown above. You may never figure out what it is, but if you had enough info, you could. The point of this, besides the Clintonesque fun of it all, is that just saying 'shit happens' can be used to avoid looking for answers. Answers that just may be figured out, if approached in a humble and methodical way. Some of this may lead to uncomfortable things, like we made a dumb mistake. Nobody likes to think they are stupid, so there is a tendency to blame anybody but ourselves if at all possible. This can lead to blaming anybody else, or nobody, rather than just facing up to the fact that we do make mistakes.
We see it on here all the time. It's the packer's fault. Somebody else picked the spot. Nobody told me. Blame the pilot. You name it - anybody but me. The point that you are fighting against is to approach this from the wrong direction. Explaining anything by saying shit happens is too easy.
This is what I, and others, are against. Sure, sometimes things happen that I don't have an answer for, but in those cases I just assume that I made a mistake but don't know what. For that, the solution is to try and do better in every way.
You see it as arrogent to disagree with you, and I understand where you are coming from. I on the other hand see your point of view as arrogent as well. You are too good to admit the possibility that you made a mistake and would rather blame it on bad luck.
In any case, it really just comes down to word games, and the whole subject is better discussed in a philosophy class, or better yet, a barroom. A bunch of drunks could really have fun with this.
;)
My final point is, what's the point? What can you do about 'shit happens?' How do you fix 'bad luck?' If you have a good answer for that, please share with the class. Some of us are here to learn.
:)

But what do I know?

Share this post


Link to post
Share on other sites
Quote

But design revisions have largely eliminated both of those mals. What would skydiving be like if riggers had simply said "oh well, shit happens"?



By no means am I saying that if a malfunction happens, that it should be disregarded as a fluke and nothing done about it. Anything that happens more than once, is not a fluke. If the cause can be determined, of course we should endeavor to try and come up with a fix.

But despite over 50 years of skydiving experience, we still get some common malfunctions, like the line twists in the original example. Maybe we've improved the odds by doing certain things, like moving the stow bands inwards. But nevertheless, we still get them. Not infrequently either. So "bad luck" seems like an apt description for whatever forces of physics sometimes cause a deployment bag to spin when it comes off your back.

Share this post


Link to post
Share on other sites
Quote

The point of this, besides the Clintonesque fun of it all, is that just saying 'shit happens' can be used to avoid looking for answers. Answers that just may be figured out, if approached in a humble and methodical way. Some of this may lead to uncomfortable things, like we made a dumb mistake. Nobody likes to think they are stupid, so there is a tendency to blame anybody but ourselves if at all possible. This can lead to blaming anybody else, or nobody, rather than just facing up to the fact that we do make mistakes.



You made a lot of good points in your post. Thank you.

And you bring up the idea that there may also be an element of psychology in the poll voting.

Some people like to believe that all malfunctions, injuries and fatalities are human error, because that way, they can assuage their own fear of such things, by reassuring themselves that they'll never make those same mistakes - they're smarter than that. So as long as they stay well-informed and well-drilled, they'll avoid that fate. It's like a salve for the psyche. It's a way of suppressing the fear from the idea that our fates are not always under our own control. No one likes the idea that we can do everything properly, and still die - that's our worst nightmare. So blaming everyone else's problems on their own human error, is a way of avoiding that kind of fear in ourselves. It's the only way they can keep getting on the airplane and convincing themselves that they're perfectly safe.

Share this post


Link to post
Share on other sites
Quote


Some people like to believe that all malfunctions, injuries and fatalities are human error, because that way, they can assuage their own fear of such things, by reassuring themselves that they'll never make those same mistakes - they're smarter than that. So as long as they stay well-informed and well-drilled, they'll avoid that fate. It's like a salve for the psyche. It's a way of suppressing the fear from the idea that our fates are not always under our own control. No one likes the idea that we can do everything properly, and still die - that's our worst nightmare. So blaming everyone else's problems on their own human error, is a way of avoiding that kind of fear in ourselves. It's the only way they can keep getting on the airplane and convincing themselves that they're perfectly safe.



Very well put!
"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

Share this post


Link to post
Share on other sites
Quote

By no means am I saying that if a malfunction happens, that it should be disregarded as a fluke and nothing done about it. Anything that happens more than once, is not a fluke. If the cause can be determined, of course we should endeavor to try and come up with a fix.



Exactly, but the mindset that allows people to accept that shit happens tends to allow them to continue to accept shit happening. It's the people who refuse to accept it that drive advances in equipment and technique. In the long run, which mindset do you think makes the safer skydiver?

The reasonable man adapts himself to the world; the unreasonable man persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man. ~ George Bernard Shaw

Share this post


Link to post
Share on other sites
Quote

Some people like to believe that all malfunctions, injuries and fatalities are human error, because that way, they can assuage their own fear of such things, by reassuring themselves that they'll never make those same mistakes - they're smarter than that. So as long as they stay well-informed and well-drilled, they'll avoid that fate. It's like a salve for the psyche. It's a way of suppressing the fear from the idea that our fates are not always under our own control. No one likes the idea that we can do everything properly, and still die - that's our worst nightmare. So blaming everyone else's problems on their own human error, is a way of avoiding that kind of fear in ourselves. It's the only way they can keep getting on the airplane and convincing themselves that they're perfectly safe.



OK John, Suppose that IS the only way they can get on the airplane. So what? Maybe somebody else needs a four leaf clover, and one needs a St. Christopher medal. How does this affect you, me, or anybody else?
I have clearly stated the danger of a 'bad luck.' attitude. Your turn.
But what do I know?

Share this post


Link to post
Share on other sites
Quote

OK John, Suppose that IS the only way they can get on the airplane. So what? Maybe somebody else needs a four leaf clover, and one needs a St. Christopher medal. How does this affect you, me, or anybody else? I have clearly stated the danger of a 'bad luck.' attitude. Your turn.



I have a lucky red rabbit foot on my gear bag that keeps me safe. It's worked for me so far. I rub it three times before every jump. You would be crazy to get on the plane without a lucky rabbit foot!

Share this post


Link to post
Share on other sites
Quote

Quote

OK John, Suppose that IS the only way they can get on the airplane. So what? Maybe somebody else needs a four leaf clover, and one needs a St. Christopher medal. How does this affect you, me, or anybody else? I have clearly stated the danger of a 'bad luck.' attitude. Your turn.



I have a lucky red rabbit foot on my gear bag that keeps me safe. It's worked for me so far. I rub it three times before every jump. You would be crazy to get on the plane without a lucky rabbit foot!


You take your gear beag up in the plane with you ?? ;)

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

0