free bag..free pack

[yarpos 4]

something that puzzles me. The BASE community is very dependent on one canopy opening, so its a very square 7 cell, similar (in shape at least) to skydiving reserve. BASE canopy is free packed, skydiving reserve is packed in a (free) bag. Is this to try and avoid horshoe mals? (maybe the free bag will clear itself), stage the opening for canopy survivability? or to fit into groovy looking containers. Would like to understand how it evolved that way.

Thanks for your thoughts, Steve

regards, Steve
the older I get...the better I was

[mark 105]

The wide bridle and freebag were originally touted as anti-horseshoe devices. (We used rubber O-rings instead of rubber bands on the bag, too, before there were "safety stows." We've come a ways!)

The bridle by itself (in a horseshoe configuration) does not have enough drag to launch the bag; Bill Booth has some interesting video to prove it.

A deployment device of some kind (frap wrap, raeper, diaper, Reuter(sp?) wrap, POD, bag, etc.) that allows line stretch before canopy inflation results in more orderly openings, fewer malfunctions and more comfort.

Not all square reserves require freebags. The Pioneer X-210R was optionally diaper-deployed, for example.

A freebag reduces to nearly zero the chance of a pilotchute-over-the-nose type malfunction.

Mark

[yarpos 4]

thanks for the info Mark. I would love to see those videos of Bill's, my intuition was that the recovery from horshoe mal theory was just something that was nice to be beleive rather than a realiable mechanism.

BASE seems to have found an answer to reliable deployment with the lines stowed on the tail of the canopy. Seems simpler (I like simple) and field tested fairly well now. Seems to work fairly well with unstable deployments also.

I guess time will tell, if the free bags keep coming off, I guess its something that doesnt need fixing. Maybe they are two different good answers to a situation requiring high reliability.

Steve

regards, Steve
the older I get...the better I was

[nitrochute 2]

para flite (the originator of the square reserve0 filmed over 100 drop tests(live and dummy).some of those drop test films were released as a super 8 film to dealers as a sales tool.it did indeed work. however as containers evolved, and freebags got tighter, the forces to extract the bagged canopy from the container increased thus resulting in the current situation. by the way, the square reseve was drop tested primarily out of a wonderhog container with no mods other than adding a rear riser to accomodate the four link set up.

[mjosparky 3]

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BASE seems to have found an answer to reliable deployment with the lines stowed on the tail of the canopy. Seems simpler (I like simple) and field tested fairly well now. Seems to work fairly well with unstable deployments also.

The use of a tail pocket for storing lines was in use by skydivers long before BASE started using it. It came about as an answer to problems with completely free packing the main. Something called "Trash packing" at the time.

Sparky

My idea of a fair fight is clubbing baby seals

[Amazon 7]

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Something called "Trash packing" at the time.

Maybe for you

I used to freepack my Parafoil all the time.. I would flat pack the canopy.... and then very neatly s fold the lines into the pack tray.. then s fold in the canopy. The Gree Star rig had a bungie that held all of the flaps in place with a little fold of the bridle that went through to the huge 36" pilotchute that stowed into a pouch on the inside of the legstrap. The long bridle went thru a couple BIG GROMMETS. one on the top skin and one on the bottom skin of the canopy. There was an x bar type slider that the bridle was connected to. Everything packed nice and neat... and made for very nice posiitve openings, Usually after sniveling for about 800 to 1000 ft. I always packed it nice and neatly. I kept screwing with the hot knife on the parapac and then with the binding tape machine.. and the grommet swage till I got the main container so tight.. that it had a PC in tow...I may have gotten it a tad too tight on that modification.

[ScottMcC 0]

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BASE seems to have found an answer to reliable deployment with the lines stowed on the tail of the canopy. Seems simpler (I like simple) and field tested fairly well now. Seems to work fairly well with unstable deployments also.

The CrW dogs do the same thing, but of course, we know that they represent the REALLY dark side!

(can't remember my 4 stack number or I'd put it)

[deadwood 0]

My opinion:

The reserve free bag system used in skydiving, along with a container that properly stages the deployment, is probably more forgiving of an unstable deployment than a typical base rig.

He who hesitates shall inherit the earth.

Deadwood
Skydive New Mexico Motorcycle Club, Touring Division

[diablopilot 2]

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BASE seems to have found an answer to reliable deployment with the lines stowed on the tail of the canopy. Seems simpler (I like simple) and field tested fairly well now.

For the most part BASE jumpers are a) more aware of their suroundings and situations, and b) not unstable at pull time.

Quote

Seems to work fairly well with unstable deployments also.

Not really. There are just some very lucky people in the world.

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

[yarpos 4]

thanks all for the feedback, its good to understand how this stuff comes about.

appreciate diablos comments about the BASE environment and stability, however I have lots of footage of BASE guys dumping on their backs, sides , while somersaulting through lines etc. Seems to toerate that, or maybe as someone pointed out luck is a wonderful thing.

I think part of my question stems from student days, when our instructor hauled out rig, started to show us the deployment sequence, then grabbed a few lines and pulled them down a few feet towards the container saying "imagine these have caught on your foot", he then continued to deploy and the speed at which the remaining stows became a tangled mess was frightening. Hence my question and leaning towards the tail pocket method.

Anyway thanks for the discussion, I love this stuff, I learn something every day!

regards, Steve
the older I get...the better I was

[darkwing 4]

Quote

...
The bridle by itself (in a horseshoe configuration) does not have enough drag to launch the bag; Bill Booth has some interesting video to prove it.

I have seen film showing otherwise. As Nitro says above, Paraflite certainly showed it worked, until manufacturers started making it harder to extract the bag from the reserve container.

It does raise an interesting question. Why bother with a configuration that was designed for a case (loose containers) that no longer exists? I still bet a bag deployed canopy has a lower malfunction rate than one not bag deployed--but then I (like the rest ofthe world) don't have data to support my belief.

-- Jeff
My Skydiving History

[faulknerwn 37]

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I still bet a bag deployed canopy has a lower malfunction rate than one not bag deployed--but then I (like the rest ofthe world) don't have data to support my belief.

I can't speak for reserve containers, but unbagged mains (I'm thinking CRW here) are extraordinarily reliable. All the things that can go wrong with bags - baglocks, spinning as it comes off your back ... that doesn't exist on tailpocketed canopies..

I suspect that the freebag system is more reliable if you have to deploy a reserve when you already have something out (pc, horseshoe, drogue). It would allow you to get the reserve into cleaner air than if it was freepacked.

W

[riggerrob 563]

I suspect that the primary reason that BASE jumpers and CREW dogs use tail pockets is to improve the percentage of on-heading openings.
A secondary function of d-bags, diapers, raepers, tail pockets, etc. is to lift lines clear of containers early in the deployment process, preventing line/flap entanglements. Just last year, an OMEGA owner suffered a line half-hitched around his main top flap.

[pchapman 262]

OPENING CONSISTENCY OF UNBAGGED CANOPIES:

I keep thinking that unbagged canopies should open less symmetrically than bagged ones, even if I don't know of much evidence to support that. As an unbagged canopy is being yanked out of the pack and the lines are being stretched out, the canopy has the opportunity to start inflating. BASE videos do show messy canopies as they get yanked out of the pack at a single attachment point, and inflations don't always proceed symmetrically. Some proportion of that can be blamed on a non-level body position. (As for the single bridle issue, there is the Multi bridle system that is used on some BASE systems to distribute the load.) Devices like a Tailgate control the opening if there's no slider. Even when a slider is used, I believe the BASE community continues to look at ways to improve the consistency of openings. (In skydiving there has been some experimentation with rubber banding sliders to lines or the trailing edge. Some techniques didn't work out well.)

Gut reaction is to prefer a nicely staged deployment, with the canopy not starting to inflate until the lines are stretched out. Putting some tension on the whole system might keep the inflation more orderly. On the other hand, I guess the BASE community is doing reasonably well with slider-up unbagged canopy deployments on long, terminal velocity freefalls.

I'd like to hear more about the opening consistency and reliability of slider-up, unbagged canopies.

BAGGED VS UNBAGGED:

> I suspect that the freebag system is more reliable if you have to deploy a reserve when you
> already have something out (pc, horseshoe, drogue). It would allow you to get the reserve into
> cleaner air than if it was freepacked.

That's one big reason we use freebags. To go further, sometimes the bag becomes a liability. A bag contains the canopy in a small volume and lets it better snake past lines and crap above the jumper. On the other hand, if the pc / bridle / bagged reserve hangs up on anything at all, the reserve may stay in the bag without the "free" part of the freebag helping the jumper. (Eg, there was a recently posted video of someone pretty much hand deploying his reserve out of the freebag after it caught up in a not fully released main. - Maybe that was the Omega caught-line incident.)

In that situation one might rather have an unbagged reserve, for it will start inflating even when the lines aren't all stretched out in the ideal deployment sequence. At least there'd be some canopy out, even if partially entangled (since now the PC would be permanently attached). I recall one ex Soviet bloc jumper saying how they liked their unbagged PZ-81 reserves (the Rogallo wing ones) because of a case where someone was well wrapped up (horseshoe or CRW?), yet the PZ-81 caught some air and pushed itself free of the entangling fabric as it inflated.

On the whole I would still guess the freebag is better on average, but there may be an reasonable argument that a non-bagged reserve (with a tail pocket) has advantages in certain types of malfunction scenarios.

[mark 105]

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[T]he square reserve was drop tested primarily out of a Wonderhog container with no mods other than adding a rear riser to accomodate the four link set up.

I can't speak to the drop-test mods, but the production square-compatible Wonderhogs had a bungee hesitator loop that held the reserve container closed until bridle extension. IIRC, they also used very short closing loops mounted on the bottom reserve flap instead of the continuous loop (like ParaPhernalia still uses on Softies) used for round-equipped Wonderhogs.

You're right about manufacturers going to friction-fit instead of hesitator loops, and I think that's when the bridle stopped being effective as a bag-launcher. The only manufacturer I know still using a hesitator loop is SSK, and then only if you can sweet talk Karen into building just one more one-off.

Mark

[nitrochute 2]

BINGO

[RTB 0]

Do line overs ever happen to CRW people?
I know they sometimes happen in BASE, I don't know that they happen a lot with reserves in a freebag.
Just trying to figure out why there is a difference, or if there is.