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koppel

Racer Reserve Speedbag/Freebag Hangups

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The Air Force Academy was experiencing some 15 mal/year out of some 850 jumps



I've asked this in the past so I'll ask again. What were the malfunctions? What happened?

What gear were they using?
My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto

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The Air Force Academy was experiencing some 15 mal/year out of some 850 jumps



I've asked this in the past so I'll ask again. What were the malfunctions? What happened?

What gear were they using?



http://www.youtube.com/watch?v=6klvGVtw-HA&NR=1


http://www.youtube.com/watch?v=5r0AkiJV5Co&feature=related

http://www.youtube.com/watch?v=6PpDZWxvU64&feature=related



Ummm...stability problems maybe? ;)










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

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The Air Force Academy was experiencing some 15 mal/year out of some 850 jumps



I've asked this in the past so I'll ask again. What were the malfunctions? What happened?

What gear were they using?



http://www.youtube.com/watch?v=6klvGVtw-HA&NR=1


http://www.youtube.com/watch?v=5r0AkiJV5Co&feature=related

http://www.youtube.com/watch?v=6PpDZWxvU64&feature=related



Ummm...stability problems maybe? ;)


Ah! I can see how a speed bag could fix that.

Thanks for the insight :)
My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto

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Ah! I can see how a speed bag could fix that.

Thanks for the insight :)




Pardon me if this is the wrong thead for this, but given the amount of malfunctions, the type of malfunctions, and the seriousness of them, maybe the Airforces method of training by taking the students straight to solo freefall isn't very wise. :| Cadet, College student, Soldiers, whatever, you never know what a student is going to do their first time up.
=========Shaun ==========


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Ah! I can see how a speed bag could fix that.

Thanks for the insight :)




Pardon me if this is the wrong thead for this, but given the amount of malfunctions, the type of malfunctions, and the seriousness of them, maybe the Airforces method of training by taking the students straight to solo freefall isn't very wise. :| Cadet, College student, Soldiers, whatever, you never know what a student is going to do their first time up.


What could possibly go wrong?! :D










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

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The Air Force Academy was experiencing some 15 mal/year out of some 850 jumps



I've asked this in the past so I'll ask again. What were the malfunctions? What happened?

What gear were they using?



http://www.youtube.com/watch?v=6klvGVtw-HA&NR=1


http://www.youtube.com/watch?v=5r0AkiJV5Co&feature=related

http://www.youtube.com/watch?v=6PpDZWxvU64&feature=related



Ummm...stability problems maybe? ;)


Ah! I can see how a speed bag could fix that.


Not sure if that was sarcasm or not. If not - how exactly would a speed bag have prevented those mals?
"It's amazing what you can learn while you're not talking." - Skydivesg

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Hi Shaun,

Please do not take this as a critique of your post ( you do still have that Chinese seat-pack that I want :P ).

The AFA ( as with all US military academies ) have, what most of us would call, the 'cream of the crop.' These are guys/gals that are well above average in academics, personal endeavors, etc. And they do not go through a simple 3-hr training program.

Now none of that will guarantee a perfect student; the videos prove that. Some times with all the training the world can offer, people simply do not take to the air as good as everyone would hope/expect.

Back in the late 60's/early 70's a local guy, who was a AFA cadet, would jump with us when he was home on leave. A great guy, very sharp & a quite good jumper; I competed against him a lot in those days. B|

He went through that program and told me a lot of what all the training is; IMO it is very First Class.

But you are right: you never know what a student is going to do their first time up.

Just my thoughts . . .

JerryBaumchen

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Hi Shaun,

Please do not take this as a critique of your post ( you do still have that Chinese seat-pack that I want :P ).

The AFA ( as with all US military academies ) have, what most of us would call, the 'cream of the crop.' These are guys/gals that are well above average in academics, personal endeavors, etc. And they do not go through a simple 3-hr training program.

Now none of that will guarantee a perfect student; the videos prove that. Some times with all the training the world can offer, people simply do not take to the air as good as everyone would hope/expect.

Back in the late 60's/early 70's a local guy, who was a AFA cadet, would jump with us when he was home on leave. A great guy, very sharp & a quite good jumper; I competed against him a lot in those days. B|

He went through that program and told me a lot of what all the training is; IMO it is very First Class.

But you are right: you never know what a student is going to do their first time up.

Just my thoughts . . .

JerryBaumchen




Back in the 80's...NickDG and I worked for a guy that ran a static line operation, he had access to and would pull a LOT of Marines out of Pendleton.

I loved teaching those guys, they were in great shape, were geared to learning that kind of stuff fast, and followed orders.

Use to amaze me how quick the classes went and how well 'most' of them did! B|










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

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"...What everyone is missing is the fact that the table or floor acts as a holding hand during a run out of a bag and canopy deployment on the ground...Observation can only be made if the bag hits nothing but air..."

I've heard a lot of "Swoop Kirwin" (famous rarified air molecules video) type wordsmithing excuses, but I'm not buying this one. If it doesn't work on a table. It doesn't work.

We went away from rubber bands on reserves for good reason. Those reasons still exist.

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If it doesn't work on a table. It doesn't work.



The line stow system of the SPEED bag has been in service for over 20 years. We used it on mains for 10 years before we put it on reserves. It has been proven to reduce malfunctions and provide more consistent softer openings. There has never been a reported problem of improper performance in the air in all that time and usage. We estimate over 5 million jumps. The USFAA demonstrated a malfunction rate of 1 in 3000 over a period of 3 years after modifying their main d-bags to a SPEED bag configuration. If you really want to test it, climb a latter and hold the bridle as you release the container, do it with the main full. That way you test the bag extraction at the same time as the line stow release.

Of course all that is not as important and germain as how it performs horizontally on a packing table.

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You have not addressed Koppel's or freefly matt's concerns.

Your explanation is that it touched the table, and that is why it took over a hundred pounds to extract the reserve from the bag. To me that is a 'Rarified Air Molecules explanation'. I'm not buying it. Please address how freefly matt's reserve freebag could hold the reserve in, if over a hundred pounds of force was necessary.

Davelpa wondered if the freebag would somehow rub up against a balled up main... Are you saying that if it did, the extraction force would then go up to 100+ pounds? Just because it touched something? Nah.

I looked at the "walking away" video of a reserve extraction, and, from the captions I gather this: You believe that it isn't important if the last rectangle/hole of the flap hangs up, because the canopy finds a way to squirt out of the opposite corner. Path of least resistance. I get that.
If that is true, then why not put a hard action snap on the flap there. After all, if you don't care if the whole flap opens, then why not nail it to the bag there and have every canopy extraction be a "squirt out of the corner?" Apparently the last corner of the flap does not always open, and you are OK with that, At least that is what the video says to me.

The design I would be looking for would be the design that allows the whole flap to open, every time, and not make an excuse about the flap corner's hang up, not take the position that it doesn't matter if the whole flap opens.

The design looks good, and apparently works, despite the flap hang ups. Why not complete the process and design it so the whole flap opens every time? Take this good idea and fix the last "bug" in it, instead of making excuses about why the flap doesn't open in some conditions; or say it doesn't matter if it does.

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I've been wondering... Why not a row of grommets instead of tape edged holes. Weight shouldn't be an issue..... Bulk doubtful and if they're set line snags should be at a minimum. Only thing I can think of negative is it'll be harder to line them up and get you hand in there to feed the rubber band through.... also the edges of the grommets could require more space than the current design has in between stows, but maybe stagger them....

From what I've seen, the knot in the rubber band lodges itself into the corner of the top flap opening and the canopy trying to expand keeps tension on it. Haven't tried a pull test but did notice a slight hang up, but it popped right open with a quick tug.
I was that kid jumping out if his tree house with a bed sheet. My dad wouldn't let me use the ladder to try the roof...

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Alexg3265

I've been wondering... Why not a row of grommets instead of tape edged holes.



Maybe because rubber bands don't really like grommets when the temperature goes up ( like the rig left in the trunk scenario );)
"My belief is that once the doctor whacks you on the butt, all guarantees are off" Jerry Baumchen

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Alexg3265

the knot in the rubber band lodges itself into the corner of the top flap opening



At least one can pack the speedbags extra carefully so that no knots protrude through the other flap.... But there still is a lot of drag from just the rubber on the fabric edges of the flap.

I wondered that if a manufacturer doesn't like the security of a single safety stow, why not go with two safety stows. Then you don't have the problem of "if one stow gets loose everything can dump out", but you still get to work with smoothly sliding grommets and fabric covered stows, that last a long time.

It might be harder to get good tension on all stows though. And I suppose bag lock concerns might be be worse with safety stows next to each other that don't easily break, although they could be spaced out. If one doesn't like safety stows, then do two rows of milspec elastics through grommets, stowing the rest of the lines in a conventional pouch. You get extra security compared to a single stow, without the problems of a large number of rubber stows through fabric holes and a large number of long line stows next to each other.

(The problem of rubber reacting with grommets gone with nickel plated ones, right? The situation is still a bit confusing to me. In 2004, NancyJ from JumpShack wrote, " It takes two to three years of extreme temperatures for a Mil Spec rubber band to break down, and frankly, brass has nothing to do with the deterioration. It's a heat and loss of moisture problem." Maybe the chemical reaction issue was more something with cheaper non-milspec rubber bands? )

Hope the good milspec style elastics last a long time on a speedbag.

Safety stows often last a decade and still can provide significant retention even if all the interior elastics have broken at the ends of the zigzag sewing. (Although I try to replace them by then even if some other riggers aren't as finicky about that.)

I accept that the reserve speedbag seems to work when it is yanked with some speed, which seems to 'pop' the elastics out better than if tested at very slow speed where many elastics can all grip the fabric flap and really increase the forces.

It's almost like it is John Sherman's "pulling the table cloth out from under the dishes" trick. :P

But I'd still like to learn more to be fully convinced.

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Deyan

***I've been wondering... Why not a row of grommets instead of tape edged holes.



Maybe because rubber bands don't really like grommets when the temperature goes up ( like the rig left in the trunk scenario );)

I was under the impression that milspec rubber bands were developed and tested to be resistant to the older grommets. Not sure if the grommet material had something to do with it. Brass does weird things. Saying they do break down.... Ok so then I could say the same thing about the two locking grommets then......... Also isn't this partly the reason for the 180 day and the "fix" of the safety stows.

I think that if they did melt and bind, we'd be seein a lot more bag locks than we do.

I do like the idea of maybe 4 locking stows (first 4). But like the bag is set up. So you'd have 2 rows of 2 grommets. Either a shorter inside flap or even use an loop of tape you could put a rubber band on and get it to the inside grommet. I think that makes sense.

I'm sure something like this has been tried and I more want to know what was the problem or con to this?
I was that kid jumping out if his tree house with a bed sheet. My dad wouldn't let me use the ladder to try the roof...

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Do you mean some thing like on the Military Javelin? Where they use two safety stows?

http://cpsworld.com/technical/technical-manuals/

Look under Mill Javelin check page 59.

I think I'd rather see 4 side by side. I've actually seen rigs where the canopy was lose and could dump out around the narrow safety stow on ether side. Leaving the center cell in the bag.

Lee
Lee
[email protected]
www.velocitysportswear.com

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RiggerLee

Do you mean some thing like on the Military Javelin? Where they use two safety stows?
Lee



Well that's nice, so my idea isn't entirely out of left field!
They separate the stows enough that the bights aren't right up against each other.
And they have both a version with 2 safety stows in the regular manner, and one with 2 safety stows with little side flaps with grommets added, an extra set of grommets for the stows to go through, so the corners of the bag are covered up -- which is another way to deal with your concern, especially when dealing with a large canopy.

(Now I've got to read some more of the manual and other docs of theirs. High speed reserve pilot chute? Sounds interesting. They allow up to 27 lbs reserve pull force. And neither CPS or Sunpath object to 365 day packing cycles if everything is stored well and the rig gets 180 day inspections. At least someone - the military - is more powerful than the FAA!)

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All of those ideas are worth trying.
One thing we agree upon is that the Free Bag and Safety Stow needs improvement. The SPEED bag has done just that and it has proven it over the last 20 years. What have the other manufacturers done to address the problem of line/bag dump/strip?

For those of you who still doubt that it is a better idea. I offer an opportunity to judge for yourself. Send a request for a SPEED bag to demo as a main to PLI. Include the dimensions of your current main bag. Jump it as a main and judge for yourself.

That is how we did it except we jumped it for years before we put it on the reserve.

The opening are smoother and more consistent and it has proven to reduce malfunctions yet some riggers continue to bad mouth it for difficult in packing and table problems.

You can't judge it on the table, drop it from a ladder or take it into the air. Remember you need acceleration due to gravity.

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