Band set up on deployment bag

[DocPop 1]

My own reasoning:

I use large bands for the locking stows and small ones elsewhere. I do not double wrap anything because if the d-bag is the right size the locking stows will be under tension anyway. If I downsize and the d-bag gets a little loose, I'll probably move to small stows on the locking stows and keep them single wrapped.

Although my non-locking stows are not tight around the (HMA) lines below the cascades it does not concern me because these do not do much except keep the lines neat during the packing process (think of reserve deployment systems).

"Line dump" doesn't cause hard openings (although it may cause other issues such as tension knots), but "bag strip" can so I do want my locking stows under tension to avoid an out of sequence deployment.

"The ground does not care who you are. It will always be tougher than the human behind the controls."

~ CanuckInUSA

[DocPop 1]

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I started doing that on my canopies after a friend told me that. He was having hard openings on his Velocities and PD told him to double stow and his problems went away.

Do you think was due to line strip? Were his locking stows very loose when single stowed?

This is the only explanation I can think of for why it might have worked.

"The ground does not care who you are. It will always be tougher than the human behind the controls."

~ CanuckInUSA

[SRI85 0]

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I ended up putting just small bands in every spot. I think double stowing the locking stows with large bands created too much tension. I did some test depoyments on the ground and i think the single stows small bands provide the best result. (well for my set up anyways.)

And how many tests do you think PD did before they put out that recommendation? Reliable results from testing involves much more than a few “table pulls” on the ground.

Sparky

Well i have seen plenty of other jumpers and riggers utilize different set ups then what PD recommends. I think they should address that in thier videos.

[bodypilot90 0]

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Do you think was due to line strip? Were his locking stows very loose when single stowed?

This is the only explanation I can think of for why it might have worked.

That's what pd said, no one ever died from a bag lock, enless they try to land it, But people have died from line dump.

[Skydivesg 7]

I can't comment on what is the correct amount of force to deploy single or double wrap stows.

However, I have been double wrapping my stows for more than ten years dating back to when I jumped an original Sabre. So I've used it on Sabres 1 & 2, Stilletto, Samurai, Katana and Velocity.

I use packers on 70-80% of my jumps and always told them to double stow everything including the locking stows. Some times they were reluctant but I always insisted and even monitored those who were shy about doing it.

I've had the advantage of seeing video of many openings specifically shot to show the opening sequence of a deploying canopy. I have seen some very ugly footage.

One of things that is quite noticable is how distorted the bag becomes during the line deployments. The top of the bag is pulled up by the pilot chute often causing the sides to get squeazed in giving the bag a trapazoid look. This dramatically reduces the tension on the line stows of which so many of you speak.

On weather days and safety day I have taken several bags of friends at our dz and emulated this distortion on the ground. It's amazing (and funny) to see the reactions of people when they see their lines just fall out of the stows in no specific order.

And bare in mind, I don't know anyone who replaces all the bands on their bag at the same time. Instead, we replace them as they break or are very near breaking. This means that some of the bands are new and the rest are in various stages of wear with huge differences in force required to deploy the line stow.

Also bare in mind that PD uses their sponsored athletes for feedback on various topics, including this one. So the recommendation is not based on just the R&D department, which for me would be enough, it includes thousands of jumps from the field.

I'm not in R&D for anyone and I'm not a rigger. I'm just some guy making a few hundred jumps a year trying not to have a malfunction and trying to stay healthy enough to make a few thousand more.

I have made several thousand jumps double stowing large bands on all my stows and I plan on making many more.

Be the canopy pilot you want that other guy to be.

[peek 21]

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That's what pd said, no one ever died from a bag lock, unless they try to land it, But people have died from line dump.

1. Who exactly said that?

2. Who were the people that died?

[stayhigh 2]

I jumped Sabre 1 and cobalt that opened really really shitty.
No matter what I did, single or double stow it opened hard.
I always tell people that if you own a fast opening canopy it will open fast no matter what you do.
ie, rolling the nose in, wrapping the tail more than others, double stowing the band.
Key to soft opening is to get a soft opening canopy.

I only single stow my lines, I did try double stowing for more than 50 jumps less than 100. and I feel with single stow initial snatch is definitely quicker but once it comes out the bag it feels the same.
Only with double stows I feel weird hesitation between PC throw and canopy out and sometimes resulting in linetwist.

I'm not saying that I never get slammer with my openings, sometimes it happens.
But I've decided that occasional hard opneing is much better than occasional line twist.
and I use very tight black small rubber bands and i have 350 lbs hma.

Bernie Sanders for President 2016

[Skydivesg 7]

I had my own technique for packing my Sabre so as not to get hard openings. It was very simple and I still use a form of it today on every canopy I pack.

Every black rubber band I've seen looks to me to be too strong and won't break when needed (maybe your's will). I've heard bad things about them from the pros so I won't use them.

I now have two of the UPT semi-stowless bags with Katana 120's and have about 400 total jumps on them. I also put 75 jumps on a proto type before UPT released it to the market and have 100 jumps on one with a Velo 103, of course they all have HMA.

The line stretch is quicker, which I like, and there is no bag dance during the line stretch phase, which is one of the big reasons I got the bags .

My locking stows are slightly longer than an inch (no more than 1 1/4) and I double stow the bands which are tandem bands.

I also figure 8 the lines and allow the stack to get slightly shorter with each turn. I don't do anything special and am a pretty quick packer.

I stow the lines up to 5-6 inches of my risers and then while putting the bag in the pack tray, I pull out exactly what I need to have the lines go down each side to the bottom corner of the tray and accross the bottom to the center.

This way I end up with exactly the right amount of excess line with no extra, which is one of the things I like about this bag.

I use packers for about 70% of my jumps including video. I've had to show packers how to stow the lines but after one or two times and then monitoring one or two times they have all been golden. Zero hard openings and zero malfunctions. I even use packers at events and anytime they are not familiar with the bag they learn very quickly.

I've had the occasional off heading opening and very rare line twist, which I know are because of me rushing my pack job.

I would strongly recommend the UPT bag. Best openings ever.

Be the canopy pilot you want that other guy to be.

[hookitt 1]

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Do you think was due to line strip? Were his locking stows very loose when single stowed?

This is the only explanation I can think of for why it might have worked.

That's what pd said, no one ever died from a bag lock, enless they try to land it, But people have died from line dump.

Line dump: Lines fall out of the stows prior to line stretch.

Bag Strip: Bag gets stripped of the parachute prior to line stretch.

It's nearly impossible for the lines to fall out of the locking stows prior to line stretch. Locking stow rubber bands generally break when line stretch occurs and the line gets ripped out of the rubber band under tension. Note: The parachute is pushing against the closing flap creating additional pressure on the rubber bands making them tighter, not looser.

Stowless deployment bags would not be possible if Line Dump made any difference in opening characteristics. The lines are not restricted but the locking stows will keep the bag closed through line stretch.

Bag strip: It can... but almost never will happen on very heavy canopies and is nearly impossible on smaller canopies. There is an interesting picture of a tandem canopy with the bag off the packed canopy just above the jumpers. The image is scary, but the end result was a normal opening.

Even with bag strip, the canopy has to start blowing open prior to line stretch or nothing unusual can be felt.

Tight locking stows are an assurance the parachute will reach line stretch prior to stripping off the bag. The rest of the line stows are for management purposes. The rest of the stows will allow the lines to lift away from the jumper.

Many people, myself included have experimented with line stows. If the bag stays shut, there is no discernible difference in the opening speed of canopies. You can stow just the locking stows and none of the other stows and the opening will feel the same. The issue doing that is the possibility of line entanglements of closing flaps so it's ill advised.

Hard openings are caused when the slider is not held up against the slider stops long enough. That is nearly 100 percent caused by packing, not line stows. A poorly managed pack job that allows the slider to be partially down the lines when the bag comes off the parachute gets your attention rather quickly.

Some parachutes are known to open faster and slower than others. A fast opening canopy with a poorly managed pack job is more susceptible to extremely quick openings. These hurt, and sometimes injure people.

A slower opening canopy can sometimes do the same thing but most of the time the opening is still somewhat slower and merely says HI!!! ... and the jumper say's "ooofff... that was fast" or other exclamations.


So all that said, don't blame hard openings on loose stows. Loose locking stows will still hold the bag shut. When the bridle starts lifting the bag, the parachute pushes against the closing flap on the deployment bag. The result is tighter stows.

My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto

[sundevil777 102]

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Every black rubber band I've seen looks to me to be too strong and won't break when needed (maybe your's will). I've heard bad things about them from the pros so I won't use them.

There are a substantial number of people that are very comfortable with locking stows that won't break, even prefer it that way. I use home-made tube stows that are much stronger than they need to be.

People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

[Anvilbrother 0]

Ive got some thoughts personally on hard openings, how we solved it, and why it might have helped.

I have had 3 military 370 mains that have all opened hard. I always flat pack them, and roll each side of the canopy all the way to the A line attachments and shove them in the center cell. I was using regular rubber bands using single stows on the bag using a 36'' non collapsible PC. Opening speeds were from 124-134 mph a reasonable range. Hop n pop openings are super soft as it should.

We switched to regular bands on the 4 locking stows single wrapped, and on the 4 outside stows we switched to tandem bands double wrapped which all accept the lines below the cascades gripping them tighter than the other bands used to.

This has made the openings very nice, on heading and consistent. I believe that the tandem bands being double wrapped take another 1-1.5 seconds to allow the stows to release allowing the PC to slow my terminal speed even slower before the canopy can come out of the bag and hit the air.

Postes r made from an iPad or iPhone. Spelling and gramhair mistakes guaranteed move along,

[rehmwa 2]

I watched Nick's (PD) vid and thought it was well presented. Double wrapping regular bands makes a lot of sense as double wrapping puts rubber to stow contact 360 degrees all the way around and it will hold better than a tight small band single wrap which only makes 180-270 (est) contact to the stow. try it.

My main goal is to make sure the locking stows come out last. 2nd goal is I'm lazy. So I'll use regular bands with doubles on my locking/grommet stows (main goal). I'll use singles with small bands on the rest even though my opinion is doubles are better there too (2nd goal - lazy).

this is a change for me from the last 20 years - I was a single wrap with small bands guy - we'll see if it matters, I've never had a bad line deployment that caused any issues, but old dog vs new tricks - I'll give it a shot - PD does the research and I'm open to it.

I got to pack and see the UPT bag and I really like it. And it fits with the idea that clean line stretch means the locking stows are the most important. I plan to convert sometime soon on my two sport rigs. My Crew rig I won't mess with, I'll continue to pack it with a shovel and duct tape.

...
Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants

[SRI85 0]

I only got about 15 jumps using tube stows on all the locking stows, and small bands for the rest. The openings seem to be a bit quicker and more on-heading. Just feels like a more pleasant opening overall. I plan on keeping this set up.

[mjosparky 4]

Using a smaller PC or one that collapses will help reduce felt snatch force/opening shock. When the bagged canopy reaches line stretch it is accelerated back to the speed of the load. The greater the differential speed and greater the drag and air mass momentum at line stretch the greater the felt snatch force/opening shock. An open PC adds to drag and air mass momentum that must be overcome for this to happen. Try and use the smallest PC that will lift the bagged canopy out of the container. Once it is out of the container and moving it produces enough drag to reach line stretch on its own.
As Hookit stated line stows do not affect opening shock. You are dealing with two things. One is staging and the other metering. Staging is used for a neat and orderly deployment of components and metering is to control the speed of deployment/opening. Nothing that happens before the canopy comes out of the bag has any affect on inflation or opening. Your slider is part of the metering during inflation/opening. If it is not up against the stops it effectiveness at controlling inflation speed is greatly reduced.
I have over 1,000 jumps on a main deployment bag built to contain the canopy and lines exactly like the reserve free bag. I use a 245 Sharpchuter which is a heavy canopy and never had a problem with “line dump” or “bag strip”.

Sparky

My idea of a fair fight is clubbing baby seals

[Anvilbrother 0]

So why did I go from having pain on every opening and going home every weekend with bruises on my legs before the tandem bands and double wraps to no pain and no marks after?

Postes r made from an iPad or iPhone. Spelling and gramhair mistakes guaranteed move along,

[theonlyski 8]

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So why did I go from having pain on every opening and going home every weekend with bruises on my legs before the tandem bands and double wraps to no pain and no marks after?

Manned up?

"I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly
DPH -7, TDS 578, Muff 5153, SCR 14890
I'm an asshole, and I approve this message

[SRI85 0]

[/url]http://www.skydivingstills.com/Skydiving/2011/Weekend-Pics-2611/15737841_ywdMT#1179781635_jG88V-L-LB[url]

Anyone wanna take a guess at this? to me it looks like a bag lock on a double stow. This happened at my DZ, but i havent got any information on it yet. But the main here was cut away.

BTW theres some pretty cool pics of the cutaway sequence right before that.

[theonlyski 8]

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http://www.skydivingstills.com/Skydiving/2011/Weekend-Pics-2611/15737841_ywdMT#1179781635_jG88V-L-LB

Anyone wanna take a guess at this? to me it looks like a bag lock on a double stow. This happened at my DZ, but i havent got any information on it yet. But the main here was cut away.

BTW theres some pretty cool pics of the cutaway sequence right before that.

"I may be a dirty pirate hooker...but I'm not about to go stand on the corner." iluvtofly
DPH -7, TDS 578, Muff 5153, SCR 14890
I'm an asshole, and I approve this message

[champu 1]

The "party line" at PD is large mil-spec rubber bands double-wrapped all the way. So whether you talk to John or Nick or Isaiah or Crystal or whoever (I feel pretty out of the loop these days) that's what they're going to tell you.

[end of PD-backed content]

If you stow your lines this way and use a pilot chute that isn't worn out, it will give you nice consistent openings because there's less difference between the pull force to release a new double-wrapped band and an about-to-break double-wrapped band than there is between a new single-wrapped band and an about-to-break single-wrapped band.

Personally? I use Ralph Ponce's small sky-bands (black rubber bands) on all stows and replace them all every 50 jumps.

[mjosparky 4]

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So why did I go from having pain on every opening and going home every weekend with bruises on my legs before the tandem bands and double wraps to no pain and no marks after?

Chad, I really don’t have a good answer for you. After making a couple of calls and doing some reading I can offer a SWAG but that is all it is, a guess.
I am guessing that because of the size of you main you are using a large PC, maybe 32/34” range. With your size and a large PC what you probably were feeling was “snatch force” and not opening shock. The differential speeds developed between your body and canopy mass, the inflated PC and related air mass momentum become very important at the moment of line stretch. That is when all of that is re-accelerated to the speed of the load, you. If the speed difference is substantial it will spank you pretty good. That is “snatch force”.
My guess and it is just that a guess is the double stows in some way are slowing down or delaying line stretch just enough to reduce felt snatch force. Once you reach line stretch the deployment sequence is over and inflation/opening sequence starts followed with deceleration. These actions are independent of deployment and not affected by line stows or the bag. The inflation sequence and deceleration are dictated by design, fill time, reefing and canopy size.
I hope this helps more than confuses. I am much better and knowing information than I am at trying to explain it.

Stay safe.

Sparky

My idea of a fair fight is clubbing baby seals