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Freebag Lockup

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Just FYI... a bag lock does not stand you up as a matter of course. It may or may not. So what's your point?

That freebag can come out in just about any body position....or it can stay locked in...as has happened before.



Yes, the baglock may, or may not, stand you up. The freebag should come out easily in both orientations.

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Yes, the baglock may, or may not, stand you up. The freebag should come out easily in both orientations.



Correct, it actually depends on the capability of your pilot chute. A good pilot chute will stand you up, right now. Free bag hang up is not really the issue here. It is whether or not the reserve pilot chute has the necessary drag to extract the bag. Some manufacturers use pack compression as a staging method (We don't). Pack compression can lead to high extraction forces as we have seen. Does the pilot chute have the capability to overcome those forces? Ask you manufacturer; make him give you numbers and test results. Make him give you a max extraction force so your rigger can make sure the bag will come out within the capability of the pilot chute. Look for “Effective Sq. Ft.” marked on the pilot chute. You can take that number times the Dynamic pressure for that speed and altitude ( See:http://www.jumpshack.com/Q.htm ) and calculate to and find the drag.

And for god sake if all you have to compare equipment on is comfort, looks, and options don’t admit it by declaration. There are too many functional issues which could be asked about.

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And for god sake if all you have to compare equipment on is comfort, looks, and options don’t admit it by declaration. There are too many functional issues which could be asked about.

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But but but...if it LOOKS good & it FEELS good it MUST be good!


Maybe if people looked a bit deeper into things the divorce rate wouldn't be so high! ;)











~ If you choke a Smurf, what color does it turn? ~

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This is all great. But what I don't like in Racers is the fact - quick loop forms a big eye (compared to normal cypres closing loop). And in freebag there is not tunnel of fabric, only 2 vertical tabs. And this big quick loop eye can teoreticaly catch some reserve fabric (or even vertical tab fabric) and cause freebag lock !

Reflexes also used quick loops, but they have tunnels of fabric in freebags.

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The Reflex actually uses a molar freebag I believe. So no tunnel (like is nicely done on an Icon) needed.

But yes one wonders a bit about that design aspect of the Racer, even if it seems to work OK in practice. The loops get pulled through under tension and ideally remain in tension during the pack job (but I'm not sure that always happens in practice). The manual does say the buffer strips are supposed to provide protection, but I'm not sure that that happens on every pack job in practice.

(And the manual still shows what seems like a 1960s military practice, as an option, to do a whole bunch of tacking through the loop. Yikes.)

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Just to corroborate John's affirmation about PC standing you up in a bag lock configuration, I was stood up with mine



My most recent (2008) unplanned cutaway was from a 90% main (brakeline trapped at the attachpoint of a centercell 'C'... long story) spin increasing/backward as the slider dropped.

So I was very verticle to the relative wind at release.

No RSL, Vector II w/ Fury 220. No discernable delay to the deployment, total loss (per altitrack) from release to normalized decent rate under reserve was right at 500'. (chop at ~1800')

Glad to have a comfortable sized reserve and quick deployment. Wife, friends and audience were glad all went smooth.

JW

PS - my only problem with my new Racer is the deployment force (ripcord). Was VERY high when first delivered from the factory. Better the second time from the factory, and my own packjobs are getting better, though still higher than I like. It also seems that, like the Reflex, it would be VERY easy for a field adjustment of the PC tension leading to a hard-pull that gets blamed on the last rigger of record. I bought it to get comfortable with the rig and its differences having never asked to service anyone elses, but I'm not at the point I would take on someone elses yet.
Always remember that some clouds are harder than others...

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And this big quick loop eye can teoreticaly catch some reserve fabric (or even vertical tab fabric) and cause freebag lock



The British brought that up some 40 years ago. We tried to fail it with a packing paddle trying to push fabric into the tightened loop. No way. We could not make it happen.
Pure speculation can only be absolved by having over 40,000 rig in the field over some 40 years and never have it to happen. The test of time would have failed it if it were to fail.

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I was under the impression that a hard arch is the worst possible position for a reserve deployment.



It probably is: The biggest impediment to a clean fast opening is burble of the pilot cute. If you are in a stable hard arch you have a big burble on your back. This can cause your poilot chute to dance around looking for the free stream.
The old saying was "Sit up and dump". The lesson was to transition from belly-to-earth to slightly vertical, enought o get the air flowing up over you back. This transition must be made with the shoulders parallel to the ground. If you drop a shoulder you will spin the bag and get line twists.
Keep your shoulders level to keep the lines at even tension. This rotation will sit you into your saddle at just the right time.
To accomplish this I look straight up over my head as to check my canopy which is exactly what I am doing, checking my pilot chute canopy.

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From JumpShack FB page:

"Parachute Labs, Inc.: This was not staged. It was just a customer rig that came in for inspection & repack. Boxing of the upper portion of the reserve container, tuck tabs and riser covers encroaching over the side flaps all contributed to holding the reserve d-bag in."



I wonder how the attached TearDrop and Zerox would handle this test...

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From JumpShack FB page:

"Parachute Labs, Inc.: This was not staged. It was just a customer rig that came in for inspection & repack. Boxing of the upper portion of the reserve container, tuck tabs and riser covers encroaching over the side flaps all contributed to holding the reserve d-bag in."



I wonder how the attached TearDrop and Zerox would handle this test...



Would THAT be a design issue?
My reality and yours are quite different.
I think we're all Bozos on this bus.
Falcon5232, SCS8170, SCSA353, POPS9398, DS239

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Maybe 15 years ago, John Sherman gave me verbal permission to sew the (Type 12 webbing) tabs together, to better prevent interference between the loop and canopy fabric. I sewed a few together, but quit after I moved back to Canada, since CSPA's old Technical Committee had a rigid attitude towards non-documented modifications.

On a related note, I have only patched a handful of reserves, but most of them were damaged by riggers who used "far more muscle than skill" to pull the closing up loop through the deployment bag.
Those clumsy souls also tried to drag some reserve canopy fabric ...
I have never had to patch a reserve canopy packed into a Racer.

That is why I never liked second-generation freebags (where the closing loop can rub on canopy fabric).
The other reason I like molar bags is that some of them (e.g. Dolphin and Javelin) help create the "crater" needed to deep-seat the exposed pilot-chute.
Not all molar-bags help create that "crater." For example, Reflexes and Wings require more special tricks - than Racers - to deep-seat the pilot-chute.

If John Sherman published a letter allowing me to sew (Type 12 webbing) tabs together, I would resume the practice, however, I believe that the long-term solution is a "shaped" molar bag similar to Javelin.

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Rob,

If you want a letter I will give you one. However, I have found no advantage to sewing the edges of the tabs together to form a channel.
As to the "Molar Bag". I have tried numerous times to build one that works. Additionally, every rigger who has ever worked for me has suggested it. I gave each one, in turn, permission and will tell you the same as I told them. "Bring me one that works better than the current design and I will change to it". To date we are still using the original design.

John

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I was under the impression that a hard arch is the worst possible position for a reserve deployment.


Probably better than tumbling randomly, which is what I see on a lot of cutaways. :S


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The old saying was "Sit up and dump". The lesson was to transition from belly-to-earth to slightly vertical, enought o get the air flowing up over you back.

I teach "feet on butt, pull and arch with hands high". This will put you in a head-high back sliding mode and should have lots of clean air flowing over the back. It's worked pretty well so far.

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However, I have found no advantage to sewing the edges of the tabs together to form a channel.
John



John,

What if you sew the tabs to the top of the freebag around the grommet?
Any cons about that?
"My belief is that once the doctor whacks you on the butt, all guarantees are off" Jerry Baumchen

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