Video: Snaped tandem bridle on deployment

[skydiverek 63]

Wow! Did I see it right?:

http://www.youtube.com/watch?v=EqR2Uu9u-o4

[DougH 270]

Damn... I have never seen that before? I wonder why it would hold for all that drouge fall and then fail on deployment.


That being said... go outside and jump instead of spending all day youtubing skydiving videos. I just got back from a CASA boogie myself.

"The restraining order says you're only allowed to touch me in freefall"
=P

[MakeItHappen 15]

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Wow! Did I see it right?:

http://www.youtube.com/watch?v=EqR2Uu9u-o4

Deja Vu?
(an article from 1990 - you know the olden days)

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Make It Happen
Parachute History
DiveMaker

[DougH 270]

Jan.

On deployment why does the force momentarily shift from the outer bridle that is anchored by the three ring, to the inner bridle?

Is this to facilitate colapsing the drouge? I guess I have to pull out an old vector II tandem out of the gear shed and take a good look at it.


Very intresting (read scary) malfunction!

"The restraining order says you're only allowed to touch me in freefall"
=P

[skybeergodd 0]

Easy answer is to update your drouges to the Sigma drouges which do not have the inner tublar, they have a spectra kill line and even if that breaks you still get main deployment(probly alittle harder opening than you want but it will still function) and also have the flex pin instead of the older small metal pin that we are used to seeing on sport rigs.

[MakeItHappen 15]

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Jan.

On deployment why does the force momentarily shift from the outer bridle that is anchored by the three ring, to the inner bridle?

Is this to facilitate colapsing the drouge? I guess I have to pull out an old vector II tandem out of the gear shed and take a good look at it.


Very intresting (read scary) malfunction!

Going on my "old-timer's" memory here...
The outer kevlar sheath takes the load while in drogue fall.
Once the drogue release is pulled the inner tubular nylon takes the load.
The length of the tubular nylon is longer than the kevlar sheath for two reasons.
One is to allow the drogue to collapse and the other is because it reaches into the pack tray to the top of the bag.

The two materials, the inner tubular and the outer kevlar sheath, move with respect to each other and create friction burns on the nylon.
(You can think of it as similar (kinda-sorta) to you pushing up a long sleeve shirt sleeve on your arm - really, really fast.)

Kevlar has a much higher melting temperature and generally did not wear out as the tubular nylon did.
The friction burns on the tubular nylon were hidden about a foot or two up inside the kevlar sheath and went unnoticed unless a packer or rigger pulled the tubular nylon out of the kevlar sheathing.

At the time I wrote that article there were a couple (2-3) of other incidents of the same thing, here and there across the country.
It all came down to proper maintenance (or really lack there of).

RWS added "Replace drogue centerline every 300 jumps." to their 1993 bulletin on
Recommended Lifetime on Vector Tandem Components. (IIRC - this was a recommendation much earlier too.)

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Make It Happen
Parachute History
DiveMaker

[diablopilot 2]

There also could have been a failure of the attachment point on the bag.

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You're not as good as you think you are. Seriously.

[mdrejhon 8]

Normally I don't reply in instructors forum but I'm a bit confused:

Is this a 1990 video or a 2007 video?

The uploader, wrote 9 months ago that he wants to jump again when he is healed up. This suggests this is a 2007 video, not a 1990 video. Can someone clear this up?

From YouTube comments:

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wtftimotronzor (9 months ago)
No they fixed him up good and proper and he should make a full recovery =) gonna take a long time tho obviously. I thought the skydive was amazing....until it went wrong =P I want to do it again when im recovered!

[skydiverton2 0]

From the black corners in the video (caused by the wide angle lens) and the color quality I think the camera is a DV camera, which was not available in 1990. (TM helmet and videoman canopy also look more recent than 1990)

As already stated this is either an inner bridle or bridle attachment failure. Both parts are not stressed during droquefall.

From the text next to the video you can read that the TM did not breakaway the main after he pulled the droquerelease (before pulling the reserve). As a TM I do not understand why?

Using your droque to gain stability is a bad habid.
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Also in case you jump a sport rig!!!

[LongWayToFall 0]

The last part looks like a 2 out downplane? Wonder why no cutaway?

[NickDG 23]

I'd imagine something like the following occurred. If he deployed the main at 5000-feet and nothing happened he'd, me, or anybody would spend the next five seconds, after the two seconds of going through the trap door waiting for main deployment, thinking, "What the hell is going on?"

He's now 7 seconds passed 5000-feet and fast approaching, or just at, tandem terminal velocity, which is a lot faster than solo terminal velocity.

So maybe he looked over his shoulder a couple of times and saw the drogue was gone and basically he was having a total malfunction of the main. Add in another couple of seconds to consider his options of cutaway and pull the reserve, or just pull the reserve, and that could have put him inside AAD firing range. (Keep in mind a tandem AAD fires at 2500-feet).

But either way, if he pulled the reserve handle, or the AAD fired, remember the main container was already opened when he pulled the drogue release. When the reserve deployed it removed what pressure there was holding the main bag in place. And Bingo - two out . . .

If that's what happened the lesson would be don't think so much and pull all the handles in the accepted and correct sequence. And he got lucky . . .

If that's not what happened, and he had another problem after the drogue bridle snapped, then he did a damn good job . . .

NickD

[jerm 0]

Goign back through PC-in-tow history (i know it wasn't a pc-in-tow, but there are parallels ('activated', yet non-out main.. chop or !chop decision, risk of 2out, etc..)) there have been incidents where the cutaway main risers have entangled the reserve lines while the main was leaving... and the 2-out fouling issues are obvious, so i imagine it could have been either way.

Landing without injury is not necessarily evidence that you didn't fuck up... it just means you got away with it this time

[skydiverton2 0]

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Goign back through PC-in-tow history (i know it wasn't a pc-in-tow, but there are parallels ('activated', yet non-out main.. chop or !chop decision, risk of 2out, etc..)) there have been incidents where the cutaway main risers have entangled the reserve lines while the main was leaving... and the 2-out fouling issues are obvious, so i imagine it could have been either way.

Yep, but there are way more accidents from people not cutting away and ending up under an main/reserve entanglement than cutting away and ending under an entanglement, so what is the safe option? STAY IN SEQUENCE

Back to the malfunction. Periodic inspection and early replacement might have prevented this malfunction. It is a single point of failure with hazardous concequence

Using your droque to gain stability is a bad habid.
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Also in case you jump a sport rig!!!

[jerm 0]

Quote

Quote

Goign back through PC-in-tow history (i know it wasn't a pc-in-tow, but there are parallels ('activated', yet non-out main.. chop or !chop decision, risk of 2out, etc..)) there have been incidents where the cutaway main risers have entangled the reserve lines while the main was leaving... and the 2-out fouling issues are obvious, so i imagine it could have been either way.

Yep, but there are way more accidents from people not cutting away and ending up under an main/reserve entanglement than cutting away and ending under an entanglement, so what is the safe option? STAY IN SEQUENCE

i wasn't making a statement about either technique being preferable, i was just saying that he didn't necessarily go out of sequence based on the main still being attached to them in some fashion. Likely? sure. Definitive form the evidence? no.

Nice attempt to start a religious war, tho

Landing without injury is not necessarily evidence that you didn't fuck up... it just means you got away with it this time

[NickDG 23]

>>Yep, but there are way more accidents from people not cutting away and ending up under an main/reserve entanglement than cutting away and ending under an entanglement,
Actually I think that's the perception, and the opposite is true. Every main/reserve entanglement that occurs we hear about. You don't hear about every instance when someone does throw a reserve into a bad main and it works.

The Army Parachute Team did a pretty exhaustive study some years ago where they were deploying reserves into pilot chutes in tow, main bag locks, and partial main malfunctions. And a freebag deployed reserves with long bridles worked in almost every case.

The big lesson here is it's always better to cutaway if you have the altitude, but at the same time if you're down and dirty don't be afraid to take the chance that just might save you.

The biggest crime is the fellow who spends his last few seconds cutting away and then runs the clock out . . .

NickD

[cpoxon 0]

Tandem Injury - Netheravon.UK - .25 August 2007

Tandem - broken bridle upon drogue release - what would you do?

Skydiving Fatalities - Cease not to learn 'til thou cease to live

[skydiverton2 0]

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The big lesson here is it's always better to cutaway if you have the altitude, but at the same time if you're down and dirty don't be afraid to take the chance that just might save you.

The biggest crime is the fellow who spends his last few seconds cutting away and then runs the clock out . . .

NickD

When you do not have 1 second to breakaway from 5000ft (tandem opening altitude) stop picking your nose and focus on your job. It takes longer to decide not to cut away than perfroming the cutaway itself

Using your droque to gain stability is a bad habid.
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Also in case you jump a sport rig!!!

[riggerrob 643]

Agreed!
... and when things get really confusing, don't waste time trying to re-invent the pull sequence.
Pull handle number one, followed by handle, number two, followed by handle number three, followed by handle number four and follow through with handle number five.

[lowpull 0]

AWESOME advice.

It is so hard to get candidates to understand that proper procedures will save your life.


That aside,the tandem I was pretty poor on this jump.


1 Lazy drogue throw,,

2 Followed by no handle touches in drogue fall.


Glad it worked out as well as it did tho


ralph

[icevideot 0]

I think the ti's are spot on with the replies.

Now can someone please tell me why the show-boating vidiot was back-flying under the tandem?

What if the bridle had failed then? The video shows very clearly the acceleration after the drogue left.

I have the skill to get that (admittedly cool) shot. I also have the experience and responsibility not to.

I hope you ti's won't put up with endangering your passengers as well as yourselves like that.

Cheers,
Robin

"... this ain't a Nerf world."

[camamel 0]

Assuming most DZ make there living with tandems I still don't understand why some of them are stretching the envelope of safety to the point of incident, accident and eventually fatality.
In each tandem Vector manual there is a recommend replacement times for every components.
I can understand that a bran new Sigma is a lot of money. But like some one said,in this thread, you can upgrade your old Vector 2 with the new Sigma technology for only a few hundreds bucks, roughly the same amount of money need to keep an old V2 drogue up to date according to UPT standard!!

Of course I was not there, and I don't know either the TM, the DZ or the DZO....exactly like a judge when you have to show up in court. But from what I can read it look like this DZ has no safety rules for the maintenance of their tandems rigs and no controls on their staff either!!
This is amasing. They jump crap until it broke down.
They don't respect their custommers at all.
This is because of attitude like this that in some country goverment want to take control of skydiving operations. Eventually we will all loose our freedom because of non responsible people like that.
If you are not intelligent or wise enought to make enough money with your DZ to have descent equipement for your custommer... please quiet the business. Those DZ can hurt all of us very bad.

This is what I think.

What do you think?

Richard

When you think you're good...this is when you become dangerous.

[freeflyer84 0]

Couple months ago I pulled the release and the loop on top of the canopy broke and the drogue went bye-bye. Bag danced on my back a couple seconds before I pulled the handles

~FREEFLYER84~
MUFF#3784

[hajnalka 0]

Just a few months ago I saw a snapped tubular kill line on a nearly brand new drogue. Jump went fine, they just landed with an uncollapsed drogue. It happened at an internal stress point and there were obvious friction burns/melting of the kill line ... I'd bet money that both drogue bridle and kill line were twisted, and the twists met in just a way that failure happened.

Like Jan's post. Thanks for that.

The forces transferred to depl. bag or canopy topskin from drogue release are strong and fast.

In this video, the drogue bridle was definitely twisted (like they often are.)

What I think:
This may not at all have been a gear maintenance issue!

And I'm happy when I see small, suspension-line-type kill lines on tandem drogues. Easier maintenance and packing if nothing else.

I'm sure that if Sigmas are the best, safest rigs out there, they will be all we'll see some years from now. The jury may still be out, and as a rigger I have no opinion .

Best,
Dawn