Can a "bag lock" malfunction be caused by an excessively large line-stow band?

[AdamLanes 1]

This post is in reference to the article on the homepage of dropzone.com about the unfortunate passing of British jumper Clare Barnes.

Graeme Windsor is quated in the article saying, "One of the rubber bands was too big so the bag would not open and let the parachute out."

Can someone please explain to me how this is possible? It seems to me that a large stow band would facilitate a faster opening.

My sympathy goes out to the family and friends of Miss Barnes.

[AggieDave 6]

It may have been something like a tandem band (obviously I don't have any information about the actual incident), but a tandem band on a sport canopy can infact cause a baglock.

--"When I die, may I be surrounded by scattered chrome and burning gasoline."

[nightjumps 1]

I have two thoughts on this:

1. The rubber band was so big that three or four rubber band wraps were made on the lines,

2. Perhaps they meant the actual stow was too long to compensate for the large rugger band and as such "may" have looped around another set of line stows during deployment causing a lock around another group of line stows.

Those are the first two things that come to mind... others may have suggestions also.

[Nightingale 0]

hmm...

what if the rubber band wasn't too long, but too wide, and got stuck in the grommet?

dunno if that's possible, its just the first thing I thought of.

[jmfreefly 0]

Or the band could have been so large that it did not hold the bight in place, allowing it to loosen and wrap around another bight.

j

[riggerrob 643]

Sounds like it was an extra-wide rubber band intended for a Vector Tandem. they are at least twice as wide as regular rubber bands and might jam a small grommet (i.e. #2) on a d-bag.
I would never use one of those monsters on a solo rig.

[tphilpin 0]

Perhaps there was nothing wrong or unusual with the line stows and rubber bands at all.

A comment about an unreleased line stow, taken out of context, when the uncocked pilot chute is actually to blame. An uncocked pilot chute in tow is not expected to release proper line stows, complete line stretch, release the locking stows, and have a satisfactory deployment.

The larger band may be a red herring.

[Squeak 17]

From my understanding from reading the interim report the band was too long and consequently triple wrapped, resulting in the band being too tight to release due to the pilotchute not beiing cocked.

You are not now, nor will you ever be, good enough to not die in this sport (Sparky)
My Life ROCKS!
How's yours doing?

[freeflyguy 0]

Don't know that situation, but...

I had a bag lock when I was triple stowing my bag. Also, in thinking about it, the couple jumps before the mal, with a couple triple stows, it almost mall'ed. That is, it 'felt' like it was going to hang up. That is hindsite

So, don't triple stow. Double is fine, but beyond that, get a different size band.

----------------------------
bzzzz

[steve1 5]

I was taught to use a couple of tandem rubber bands on the first two stows. The guy who taught me this had a bag lock last summer. I'm not sure, but I think it could have been caused by these larger rubber bands. I still use tandem rummber bands on the first two stows but I make sure these stows are short and will release without too much pressure. Both my rigs have fairly small bags and it's hard to get them closed up properly without the extra strength of these two rubber bands.....Steve1

[fergs 0]

Quote

I was taught to use a couple of tandem rubber bands on the first two stows. The guy who taught me this had a bag lock last summer. I'm not sure, but I think it could have been caused by these larger rubber bands. I still use tandem rummber bands on the first two stows but I make sure these stows are short and will release without too much pressure. Both my rigs have fairly small bags and it's hard to get them closed up properly without the extra strength of these two rubber bands.....Steve1

Steve,

If someone came to me and asked about using oversize bands on the locking stows, my reply would be:

1. Get rid of them and change to regular sized bands or tube stows
2. If deployment bag is too small, then learn to psycho pack to get the canopy in there easier.
3. If Psycho packing doesn't fix the problem, get a slghtly bigger deployment bag.

There's enough evidence on too large locking stow bands to have us all get the hell rid of them. Your problem of deployment bag size may indeed be cured with a nice tightly rolled psycho pack job coupled with standard size bands / tubies.

Blue Skies,

fergs

[steve1 5]

Fergs,
I do psycho-pack and really like it. Maybe I will trash the larger bands. No sense taking chances. Thanks.....Steve1

[mjosparky 4]

Quote

Perhaps there was nothing wrong or unusual with the line stows and rubber bands at all.

A comment about an unreleased line stow, taken out of context, when the uncocked pilot chute is actually to blame. An uncocked pilot chute in tow is not expected to release proper line stows, complete line stretch, release the locking stows, and have a satisfactory deployment.

The larger band may be a red herring.

Tony,
It think you hit the nail on the head. With a fully functioning PC any stow band that does not release will break. At terminal a PC produces over 100 pounds of drag and I have yet to see a stow band that can take that kind of force. Take any stow band you would like, double it or even triple it. Then hook it to 100 + pounds and see if you can pick the weight up with the band.
Sparky
Sparky

My idea of a fair fight is clubbing baby seals

[ernokaikkonen 0]

Quote

With a fully functioning PC any stow band that does not release will break.

Eventually, yes.

My only cut-away was caused by double-wrapping a rubber band through a grommet. I was told not to do it, but I was too lazy to replace the rubber band.

After I threw the pilot chute, I was surprised with the absence of the usual opening shock. Looking up, I saw my D-bag, with the canopy still inside, spinning at the end of my lines. I had time to think "hmm, that might become a problem" before the canopy got out of the bag, spun up, and put me on my back.

The actual cause of the mal may have also been the fact that the tension on the double-wrapped stow was just different from the other stows. Nonetheless, I'm not doublewrapping locking stows anymore, even though I know people who keep doing it successfully.

[phoenixlpr 0]

Khm, Its no universal answer. I do doublewrap all line stows, but I(we)m using long ones. My stows are about 3-5cm long.