hook-in failures

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Tad Eareckson
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hook-in failures

Post by Tad Eareckson »

In the space of slightly over three quarters of a decade (1998/01/10 to 2005/10/01) we had, amongst the neck of the woods crowd, hook in failures at ridges resulting in serious multiple fractures, a bruising tumble down a steep slope (1998/04/28 ), and a fatal fall.

Eight (?) days ago there was a tow related hook in failure resulting in some horrible injuries. Less than four weeks before that (2007/09/22) there was a nearly identical failure at a tow operation (Albuquerque?) which was followed by a twenty mile flight because Murphy's saintly twin was on the day shift and screwed up a radio long enough for the oversight to be noticed.

When something bad happens those of us who aren't surgeons or morticians can't do much more than discuss the issues to try to reduce or eliminate the possibility of it happening again - which is what just about every participant in the other thread was doing.

Steve and I collectively have over a half century's worth of being in the sport but neither of us had ever come across the "wrap/unwrap" phenomenon. Brian's experience indicated that it was, indeed, real and one needn't be an idiot to become its potential victim. Now we have at least a couple more people who are aware of a potential danger and have an idea of how it manifests itself.

Didn't realize a discussion of numbers and real versus imagined dangers qualified as a rant. Must be some discrepancies in dictionaries.

The most serious shortcoming of our aircraft is that the cockpit is normally stored separately from the wing and the status of the connection is not apparent to a pilot staring down the runway with the downtubes on his shoulders.

There's only so much we can do when the runway is a short steep wooden ramp over a boulder pile but when it's flat ground surrounded by more flat ground and you're proned out on a platform or dolly there are a lot of requirements that are going to be difficult and virtually impossible to screw up.

On Sunday evening (a short time prior to the announcement of this latest life altering event) I asked about the history of AT foot launches at Ridgely. They guessed something around four in their nine seasons of operation to date. Not coincidentally, I think, that's about four more than the number of serious launch incidents they've experienced over the period.

Maybe we should be taking a look at how long it takes for a dolly to pay for itself in terms of the launches blown, downtubes broken, and pilots dragged and mangled in its absence.
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jimrooney
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Post by jimrooney »

Oh just for fun I guess:
Clarification of why I term your "discussion" a rant...
It (backup hang loops) had nothing to do with hookin failures or the Vegas accident (the topic of the thread). Even "Off Topic" would have been appropriate.

When someone gets off the paved road and starts tilting at windmills, yes, I consider that a "rant". I don't think I'm off base here.

Just as I fully expect a 10 page rant after I post this.
(which is why you won't find me posting to this thread again... I have no interest in a one sided "argument")

Funny thing is that if you didn't blather on and on and on... if you used one iota of tact, people might actually listen. But I guess there's no hope of that. Oh well.

Have fun.
I'm going to go find something useful to do.
Flying Lobster
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Post by Flying Lobster »

I think what Tad is saying here is that all launches are safer when done off of dollies.

I'm going to see if I can borrow a couple of dollies from LMFP and roll off of Henson's on them. It occurs to me I might need a dolly reserve and a retrieve line (weaklink too?). Any ideas?

marc
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Tad Eareckson
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Post by Tad Eareckson »

Oops. Was only thinking hemispherically with respect to ridge associated neck of the woods crowd statistics. Add one that ranked second in seriousness for 2006/02/21 and extend the time period another 112 days.

By the time this latest accident was announced on this forum the best information available indicated (and still does) that Bill had neglected to make any attempt to connect his carabiner to anything.

The issue of backup suspension was first and shortly thereafter raised by Brian.

All of my references to backup suspension were in response to questions and points raised in half a dozen posts by the aforementioned and Marc and Jim.

Yeah Marc, I've got a few ideas...

1. You might want to read what I said in Paragraph 7 of my previous post before you match your smart-ass comments with a comparable flight plan. But hey, do as you see fit.

2. Nah, skip that one.

3. Tell us, please, what the downside is to using a dolly for tow launching wherever practical.

Christy,

Thanks for the refresher and additional information.

I'd sure crawl through a lot of thorns and tarantulas to get my hands on that thing. I wonder if it's possible to run out of thread on the bobbin and continue to fabricate something that looks like it's stitched. I'm glad the backup was black.

Weird. I'm thinking the overlap must've been at the middle of the Lark's Head used to "secure" the loop to the keel. Otherwise the nonfunctioning webbing should have come down with the glider.
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Post by Flying Lobster »

Nothing wrong with using dollies for launching.

Did it have anything to do with this accident?

No.

Does the supposed uselessness of back-up hang loops have anything to do with this accident?

No.

(BTW, search as I might, I couldn't find your quote on the Wills Wing Tech Bullitin site--but I DID find a warning that stitching on a hang loop can degrade and fail long before the webbing itself is compromised)

About as silly as rolling off a ramp on a cart.

marc
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Tad Eareckson
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Post by Tad Eareckson »

What accident? Check the topic. This thread is about hook-in failures.

No, this most recent accident had nothing to do with using dollies for launching. THAT'S PRECISELY MY POINT. Let me spell it out for you again -

IF A DOLLY HAD BEEN USED THE ACCIDENT WOULDN'T HAVE HAPPENED.

No, of course you didn't find the quote in a Wills Wing tech bulletin. Go back to my post of 2007/10/23 and read Paragraph 13.

Yeah, the stitching can degrade and fail before the webbing. The same stitching and webbing is used above and below the carabiner. Have you ever seen harness suspension backed up? Do folk replace harness mains every twelve months or three hundred flights, whichever comes first? Has there ever been an incident of a Wills Wing primary failing anywhere in the world in the history of the company? Reaching farther - Has anyone ever heard of any primary failing anywhere outside of Guatemala?

Has anyone ever heard of a Wills Wing leading edge or cross spar failing?

No, backup suspension had nothing to do with the accident of 2007/10/18. See Paragraph 1 of this post. With respect to the discussion of backups pertaining to this most recent - See Paragraph 3 of my 2007/10/27 post. See also the many references in the thread on the Hang Gliding forum on which this accident was first announced.

Marc, please go back and read Paragraph 7 of my 2007/10/26 post - over and over and over. Then get somebody who ISN'T functionally illiterate to explain it to you.

Never mind - Here it is:

>
There's only so much we can do when the runway is a short steep wooden ramp over a boulder pile but when it's flat ground surrounded by more flat ground and you're proned out on a platform or dolly there are a lot of requirements that are going to be difficult and virtually impossible to screw up.
<

If you just keep repeating a lie long enough you can:

convince people that Stella was driving and the car was moving when she spilled the coffee and got a mild burn;
swing an election;
invade Iraq on the pretense that Saddam Hussein was behind the 9/11 terrorist attacks.

It's a sleazy tactic but it works.

You got any ideas of your own to reduce this sort of carnage?
Flying Lobster
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Post by Flying Lobster »

There was an accident out west a couple of years ago which involved a failed hang strap.

Redundancy is there in the event the main fails FOR WHATEVER REASON. This includes improper attachment or failure to hook in altogether.

Why do I take exception to stuff that you post like this? Because lesser-experienced pilots might be gullible enough to actually believe what you say and forgo using a back-up. Just having two to check during your hang check INCREASES the probability you'll be attached to at least one properly.

Your posts tend to be so convoluted in both logic and premise it's generally hard for me to get anything meaningful out of them--but let's take a look at your dolly issue.

This is another example of a classic Tadism--which basically boils down to
"Do as I say or you all are going to die."

The absolute only thing that using a dolly adds to the accident scenario in question is that the LAUNCH begins with the pilot proned out. Your point is that if this launch (and hence, implicitly all launches) began in a manner which it is impossible to not be hooked in (while ignoring the many things that can happen with the cart itself, BTW) it wouldn't have happened.

Like Doh!

marc
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Flying Lobster
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Post by Flying Lobster »

Forgot to mention, Tad. I'm willing to bet you that I can come up with far more examples of launch accidents involving dollies than foot-launch tows.

marc
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Tad Eareckson
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Post by Tad Eareckson »

This never sinks in but - what the hell...

Jim's never gonna let a statement from the manufacturer interfere with his concept of why the manufacturer does something.

VGs are backed up with steel 'cause they're VGs - regardless of whether they're Talons using synthetic fiber or HPATs using steel transmission.

Fabric to metal connections do not wear. Walk around the setup area and try to find worn suspension (like I did) (and trust me - those straps aren't being replaced every twelve months or three hundred flights, whichever comes first). The only wear you will find will be as a result of the fabric to fabric connection effected by the ill advised practice of sawing the webbing in half with a tie-down rope.

The harness suspension/carabiner interface is a fabric to metal connection. It doesn't wear and it isn't backed up.

The downside of using backup suspension is a little or a lot - depending upon the configuration - of extra drag. The upside is an inflated feeling of security for people who don't do much thinking about the stuff below the carabiner.

Yeah (forgive me Christy), in my opinion - Ole is right. It was pilot error. Just like almost all aviation incidents and disasters. Probably not pilot error in the sense he is probably trying to convey, but nevertheless...

Let's take Christy at her word - and I do - that the loop was Lark's Headed onto the keel, the carabiner was engaged in the loop, shortly after launch she dropped abruptly into her secondary, and what was left of the primary was lost on the slope.

The one inch nylon webbing didn't fail - the stitching failed.

Was the hang loop adequately inspected/preflighted? I really doubt it (feel free to chime in).

Should the individual at the sewing machine be taken out and shot for attempted negligent homicide? A bit oxymoronic but - yeah. Was Ole negligent? Yeah. (Really sorry to hear about yet another mangling.)

Would I - in those circumstances and at that time have also suddenly found myself eight inches lower than I wanted to be - undoubtedly.


Somebody gets a new harness from Wills Wing, the suspension stitching is inadequate, the problem manifests itself at five grand in a thermal surge.

The glider's gonna come down in pristine condition cause the parachute will stay with it and deploy.

The pilot, as he accelerates to terminal velocity (special emphasis on terminal), will be thinking, "Damn. I really wish I hadn't trusted somebody upstream and had properly inspected my equipment just like it says in the preflight checklist."

Pilot error.
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Post by Flying Lobster »

Metal to webbing wear does in fact occur--and is a known reason for weakening webbing. I know this first-hand from decades of climbing experience and have witnessed and know of many webbing failures. Anywhere there is metal to fabric contact there is inherent wear and weakening of the overall load-bearing strength of the webbing. Furthermore, constantly loading of areas like the biner contact cause dirt and metal compounds to be abraded into the webbing--further weakening it. Anytime a webbing is loaded over a sharp edge it can be cut at a very low loading factor which is a fraction of it's ultimate tensile strength. If you do not believe any of this, I recommend you contact the manufacturers of webbing themselves and ask them.

marc
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jimrooney
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Post by jimrooney »

Fabric to metal connections do not wear.
BWAHAHAHAHAHAHAHA!
YOU ARE ON CRACK!

I've yet to meet the pilot dumb enough or arrogant enough to fly without a backup loop. Perhaps you'll be the first then?

Thanks, I needed a laugh
Tad Eareckson
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Post by Tad Eareckson »

Marc,

Nice to see you're in one of your more rational, constructive cycles.

I'd REALLY like to hear something less vague than an undocumented reference to a hang strap failure sometime somewhere out west.

I'm not real happy about again seeing quotation marks around something I've never said or suggested and for which you will find nothing similar in any archive to present as evidence. But just keep repeating the lie and weak minds will follow.

Is there the remotest possibility that you will address the issue of Mike Meier's statement on the subject? Or is he too much of a recognized authority for you (or any of your debate comrades) to take issue with? (Much easier to take on Whacko Tad.)

Experience will have no bearing on whether or a pilot decides to take some useless webbing out of the breeze. Intelligence and logic will be the determining factor.

Several years ago I started taking a look at some of the junk in my suspension system that was doing nothing but slowing down my glider.

A backup connection between my parachute bridle and steel carabiner in case I got sucked up into a cu-nim, bailed from the glider, freefell clear, hit the silk, and the carabiner failed? Yeah, right.

A parachute bridle routed all the way up to the carabiner so my glider would come down at a more comfortable angle under the silk? Next.

The backup loop went in the bag and I declared my intentions to Sunny and asked if that would be a policy issue.

His response was, "No. It's your life."

And I said, "No, look. I've got exactly the same material and stitching between the harness body and carabiner as between the carabiner and glider."

He looked, thought, and said, "Hmmm... You're right."

Yeah, me and, I found shortly thereafter, Mike are right.

I'm still not sure you've got a good grasp of my statement regarding dollies so I'll try again.

1. The north ramp at the Pulpit, the slope at High Point, and the cliff at Whitwell are not particularly good places to dolly launch.

2. Just about any tow site anyone can name is.

Yeah, if a launch begins with the pilot proned out he is most assuredly hooked in. (By George, he's got it!)

But damn! I forgot about all of the terrible side effects of dolly launches! New crusade! I'm gonna work on convincing the Ridgely idiots that either they're closing their eyes to a situation they do not wish to acknowledge or they are not aware of the caliber of disaster indicated by the presence of four launch dollies in their community. Ah, what the hell. I'll just sneak over after the end of the season and cut 'em up for scrap.

Yeah, if you loop your suspension around a buck knife, that fabric to metal connection is gonna wear (fast). But I'm talking about webbing in a glider environment. Wills Wing (I'm limiting my comments to Wills Wing 'cause that's the scene with which I'm most familiar) doesn't hone their suspension hardware to fine edges.

I've got, as you pointed out earlier Marc, an old glider - probably the oldest glider that flies at Ridgely. Acquired it sixteen years ago come Saturday. Sometime not long thereafter I hand stitched my own (kingpost mounted) suspension out of a one inch tubular nylon base and have been flying it ever since. It - to date - shows ZERO SIGN OF WEAR. About the same as I've found strolling through the setup area.

Can anybody whip out a camera, switch to macro mode, and post a jpeg documenting any more wear than I've found? Never mind, I'll take your word.

I keep it clean and out of the sun so there's no reason it shouldn't be about as strong as the day it went on but let's be real generous and cut its integrity in half. So now I leave the glider when my carabiner is loaded to two tons instead of four.

Anybody out there ever load up to anything remotely approaching four thousand pounds?

Anybody?

Well, while I'm waiting...

Jim, you still don't show much indication of having read things upon which you comment but, although you have indeed met a pilot dumb and arrogant enough to fly without backup, I couldn't possibly be the first of the breed. Wills Wing only started installing backups when they caved to the "We want fins on our fenders!" crowd so for the duration of that period it's a pretty safe bet that every single one of their gliders that shipped was test flown sans backup.

I'm pretty sure you've met Rob Kells and there's very little doubt he's at least as dumb and arrogant as I am. I'll send him your regards.

So, Marc (and Jim), if the carabiner contact is such a critical area 'cause of the:

fabric to metal phenomenon;
constant loading; and
dirt and metal compounds abrasion

with respect to the HARNESS webbing at the carabiner interface...

1. Do you back this up?

2. How often do you replace it?

3. Have you ever heard of it failing?

4. Have you ever seen the slightest evidence of wear?
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jimrooney
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Post by jimrooney »

Gee, how did I know there would be a 5 page response?
I'm not real happy about again seeing quotation marks around something I've never said or suggested and for which you will find nothing similar in any archive to present as evidence.
What?!
I copy/paste.. I'll do it again, just for fun...
Fabric to metal connections do not wear.
Several years ago I started taking a look at some of the junk in my suspension system that was doing nothing but slowing down my glider.
You actually think what's holding you back is a piece of fabric? One that's sewn to an other piece (imperceptible drag difference) is slowing you down???
I call Bullshit.
If you're so damn concerned about drag... GET A DIFFERENT HARNESS.
The harness makes differences on an order of MAGNITUDE more than a strap. For that matter, plug up the kingpost hole.
Drag?... BULLSHIT.

Try this on for size... I have (personally) seen degradation of the hangstrap at both the caribiner and glider end.

You are officially the first pilot I know that's dumb enough and arrogant enough.

Jim
RedBaron
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Post by RedBaron »

I think Tad is right. From now on I'm gonna fly my Falcon without a backup hang loop for increased perfomance and without a chute for increased sink rate. None of them will do me any good if my harness suspension fails anyway, so what the hack, right?
All feuds and awkwardness and hesitation to post aside, I never thought about these things before and it indeed is true that the weakest links in the chain of structural integrity are not backed up. Everything in a hang glider can be assigned a probabilty of structural failure (POSF). Removing the back up's of structural parts that are less likely to fail will result in a net increase of POSF of the entire system and thus will make the entire system less safe. Whatever tiny % of reduced drag you may gain from removing the backup hang loop (and this is what makes me giggle), I'm sure you sacrifice as much of your total structural integrity.
Let me ask. From a safety point of view, wouldn't the right logic be to think about how to back the harness suspension in order to gain a net decrease in POSF? I for one may buy one of these tiny harnesses for rock climbers. They easily fit under a hang gliding harness and can be secured to the carabiner via climbing rope that is routed through the velcros of the suspension webbing. I'm sure the added amount of drag will be unacceptable for most recreational pilots on 20 year old gliders but the idea kinda keeps growing on me.
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Post by brianvh »

Tad - you are suspending yourself on tubular nylon?!! I had to go back and reread that to make sure I have it right.

Ask Betty Pfeiffer about using tubular nylon. She'll start gasping and choking. When I described our suspension system to a friend who is an experienced caver (read rock climbing in more extreme conditions), his first question was "is that hang strap tubular?". One nick and it will supposedly unravel under stress.

Nope, this dude doesn't need a backup.

But I guess it has a more aerodynamic profile than flat, right? That's what matters.
Brian Vant-Hull
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Post by deveil »

i'm gonna make popcorn!
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Post by hepcat1989 »

I'm gonna go puke.....
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Post by deveil »

well yeah, that could be fun to watch too. but i think this might be getting even better. pull up a chair (but Do keep a bucket nearby).
Tad Eareckson
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Post by Tad Eareckson »

Jim,

Five pages shouldn't bother you, you never seem to actually read much of anything anyway. The issue of the quotation was addressed to Marc (although there's no shortage of misattributions from you in the past - either).

I'm not interested in replacing my equipment. I was just getting rid of a few items of useless clutter.

Let's address the carabiner end of the suspension. Was there identical wear in the webbing of the harness that went with the glider?

If so the backup loop wasn't doing any good.

If not it's a real good bet that the wear was caused by abrasion from the tie-down rope. Pilot error.

OK, the glider end. Let's say the damage was caused by contact with a no-skid strip (sandpaper). Glider manufacturer and pilot error.

Let's say the wear is occurring with some hardware that can't be improved upon. If the damage was significant enough to be a concern it should have been replaced already. He shouldn't have been flying with it. Pilot error.

You don't use a backup so you can go for several years between the most cursory of preflight inspections. Anyone incapable of evaluating suspension will be much less capable of detecting side wire damage.

Janni,

>
I never thought about these things before and it indeed is true that the weakest links in the chain of structural integrity are not backed up.
<

Yes. A sign of intelligent life - finally! Someone finally understands what Mike Meier was saying with

"...there's no other component on your glider that is backed up, and there are plenty of other components that are more likely to fail, and where the failure would be just as serious..."

I got at least one person to think about something he hasn't before. Cost/benefit ratio sucks so far but I'll take whatever scraps I can get.

The last two sentences in your paragraph are wrong, however.

If you have single suspension that fails at twelve Gs and a cross spar that buckles at seven, you toss your 'chute right after seven. If you back up your suspension with twenty-four G webbing, you still toss your 'chute right after seven.

You don't design a plane by building a bunch of crap and backing it up. You design a plane by building everything well, as strong as it needs to be, and as light and economically as possible.

Since there's virtually no weight, drag, or cost penalty to stitching up some suspension that will withstand over three times what the rest of the glider will, that's what Wills Wing does. It doesn't need to be backed up.

No - while I'm delighted that you seem to be getting the idea that it's pointless to exceed the strength of the stuff below the carabiner with that of the stuff above - backing up the harness suspension gets you NOTHING. Your glider became toast at a fraction of the loading your harness can withstand and the point at which your (pick one) leading edge snapped/cross spar buckled was the peak of the loading with which your harness has to contend.

It's not broke - don't fix it. When someone pulls up to abruptly from the bottom of a loop, primary suspension and harness webbing failures are two things that don't happen.

Brian,

My first glider was a UP Comet 165 with sandpaper suspension position fixing and a stitched one inch tubular webbing primary loop. If that didn't kill me - or at least drop me a couple of inches - nothing will.

Back then there were zillions of gliders using tubular webbing suspension getting the crap abraded out of them and I don't recall anybody ever making it to the secondary.

When I stitched up my suspension I used the tubular 'cause I had a piece about the right length and I didn't feel like cutting into a long stretch of flat. It's kingpost mounted, my base webbing does not directly engage the tangs, and I've got some light flat webbing reinforcement/wear protection sections (which don't appear to be needed) at the spreader bar and carabiner contacts.

While I have every confidence in Betty to keep a harness connected to a glider or one of her parachutes, I've got a long list of very good reasons not to gasp and choke at everything she does.

Thank you for your inclusion of the word "supposedly" but let's say it does. That webbing is never in range of anything that can nick it.

Now let's fabricate a scenario involving a midair and a lot of jagged metal. I'm thinking it might be a real good idea to be separated from the tangle of whirling wires and sharp edges of the junk heap that used to be my glider anyway.
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Spark
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Post by Spark »

Tad Eareckson wrote:...Brian,

My first glider was a UP Comet 165 with sandpaper suspension position fixing and a stitched one inch tubular webbing primary loop. If that didn't kill me - or at least drop me a couple of inches - nothing will.
So the quote stands ... ready for the test of time ...

... arrogance precedes disaster ...

a belated happy halloween, dude.

'Spark
XCanytime
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I DISAGREE

Post by XCanytime »

If not it's a real good bet that the wear was caused by abrasion from the tie-down rope. Pilot error.

OK, the glider end. Let's say the damage was caused by contact with a no-skid strip (sandpaper). Glider manufacturer and pilot error.

Tad,
Pilots (and glider manufacturers) do commit errors. Hence the need for a backup JUST IN CASE the pilot (or the glider manufacturer) commits an error. Nobody is infallible! Not even you. You can't label everybody who disagrees with you as less intelligent as you. You are not going to win friends and influence people with your sarcasm and by berating them as having weak minds and less intelligent just because they choose to disagree with you. In this country everybody HAS THE RIGHT TO DISAGREE.

Bacil
Danny Brotto
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Worn Mains...

Post by Danny Brotto »

Well I for one had a harness that needed to be replaced because the mains showed significant wear where it met the front of the carabineer. The HES cocoon that I used from circa 1988 to circa 2004 was retired due to this wear. (If pressed, I can dig the harness up out of storage and take a pix.) I purchased another just like it in 2004 to replace it. BTW a cocoon harness does have the mains backed up by the other suspension lines. They are independent from the mains.

In the “old days”, tubular webbing was quite acceptable and even preferred over poor quality flat web hang straps of the time. (In one of Pagans books or articles we shows how to tie one using (I think) a water knot.) A well know but now defunct manufacturer even shipped gliders with ¾” tubular main material. We did see problems with poor stitching (cross instead of zigzag) and incorrect stitch material (cotton instead of synthetic) at times. And yes, I’ve seen questionably worn primary hang straps on high-time gliders (sorry to out you Millman.)

The point is that we used to use tubular webbing like we used to use aluminum carabineers. The UP AXIS and TRX used 9 mm perlon climbing rope tied using double a grape vine knot. Safety systems have evolved, as has our understanding of suspension systems.

I fly my U2 with the stock suspension; a backup integrated within the main. The two loops however are functionally separated. The main is connected to the kingpost with tangs on either side of the kingpost. The secondary connects using a d-ring carabineer around the keel. It may look like a single suspension but functionally the stock WW suspension system includes an integrated but separate backup.

I will only fly with a backup if only to appease my weak mind.

Danny Brotto
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Post by RedBaron »

Hmm, obviously everything else will fail before the main hang loop or the harness do, provided all equipment are properly designed and maintained. The latter I take issues with. It seems to exceed my competence to tell if they are or not beyond the very visble tear and wear stuff. What if I was sold the one harness that was overlooked in quality control and is destined to fail after 300 hours? A .0001% chance of that happening is big if certain death is the consequence. But then, who am I kidding, I'm still smoking LOL
Tad Eareckson
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Post by Tad Eareckson »

Brian,

P.S.

I dug the suspension I removed from my glider after acquiring it from Dennis Pagen. I'm pretty sure it's the same assembly that shipped with it originally. Integrated primary and secondary.

If I really felt the need for a backup and were only given sufficient lengths of two flavors of webbing with which to work, I'd use the strong stuff for the backup.

In this assembly the primary is Type 18 flat, the backup is tubular - identical down to the white color and gold marker thread to what I used in slapping together my then primary/now only suspension.

Like Mike and I said - It's there for show.
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Mike Meier

Post by XCanytime »

Hey Tad,
What exactly did Mike say about the backup hang loop and when did he say it? Did you ever read Mike's article "Why Can't We Get a Handle on This Safety Thing?" in a 1998 magazine? I believe it is also on the Wills Wing website. In the article Mike does some soul-searching after crashing during a top landing attempt during a test flight in midday conditions at Crestline. Turns out he thought since he had done top landings during test flights in midday conditions thousands of times and never had a problem that it wasn't that dangerous. Well, one test flight of a Spectrum ended in a top crash landing that shock loaded his spinal column enough that he was in some pain for weeks after the crash. This forced him to rethink his logic and realize that he was playing the odds a little more than normal by attempting to top land in midday thermal conditions at Crestline.

Bacil
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