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Auryn

How to "safely" use your reserve?

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This is a sort of spinoff thread from the incident forum about the base jumper that went in from a helo in Cinci, OH.

The question that seemed to be brought up was "are base mains safer than skydiving reserves b/c they are packed more or less the same way as reserves and are (mostly) deployed at the correct altitude, while stable, whereas skydiving reserves are (as was implied) not deployed stable?"


I think the incident report, and many others from base indicate otherwise. There is a critical component missing from this post. BASE mains are by and large throw-outs while skydiving reserves are ripcords w/ a spring loaded PC.

The deployment system makes the difference between the two IMO (and I've read all the skydiving fatality reports since 1998 and ALL the base reports)

Bryan

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I've got 13-14 reserve rides. All of my deployments have been stable. Maybe that guy should learn to arch as he cuts away.:S Most people aren't trained to do that, BTW. I trained myself to do that. ;)



Happened so fast when I cut away I don't think I had time to arch. :D I hesitated on the reserve pull after I cut away, but the RSL actually popped for me pretty quickly (there was about a 2 second lag between the cut away, hanging there and the the RSL releasing), after that I dropped and the reserve was out so quick I wasn't in free fall again for maybe 2 seconds.
Rodriguez Brother #1614, Muff Brother #4033
Jumped: Twin Otter, Cessna 182, CASA, Helicopter, Caravan

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From up close and personal observation of about 1200 spring loaded PC deployments, they almost always work OK, but work better when the jumper is not quite stable. Head high or low gets a more reliable launch, although we're talking about the difference between 98% and 99% here.

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I've got 13-14 reserve rides. All of my deployments have been stable. Maybe that guy should learn to arch as he cuts away.:S Most people aren't trained to do that, BTW. I trained myself to do that. ;)



One of the times I chopped (it took me a little while to figure out that you had to fly elliptical canopies through the opening sequence, and that some things like skysurfing and wing suits were not ideal matches for small fun parachutes) I left on my back, spinning, and with more than enough airspeed to roll 180 degrees stop spinning before dumping.

After the wrong spinning malfunction you won't be belly-to-earth, and you may not be parked about your yaw axis (one riser may have released a bit before the other, although I was pretty motivated to disconnect the pair at the same time).

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Its comparing apples and oranges.

Both systems have the same task but work very differently as we all know. Since BASE jumping i have actually became more fearful of Skydiving equipment and all the added components.

My priorites are

Altitude allowing: Get stable, Pull (i dont use RSL but thats not the discussion here)

Altitude not permitting: Just get as much fabric out as possible, you maybe just sacrificed a stable opening for going too deep.

One thing i will say is I trust my BASE rig a whole lot more not because i have to, but because its so simple. Yea its one canopy but done correctly its the best fucking canopy you could hope to have above your head and i have peace of mind knowing I packed it. I want my riggers ticket just so i can pack all my own shit, legally anyway.
1338

People aint made of nothin' but water and shit.

Until morale improves, the beatings will continue.

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Reserves are engineered and packed to open fast but not so fast they kill you. I've never opened one at terminal but at subterminal they open very "crisply". I would trust a skydiving reserve before a base canopy. I think they are better tested. Finally adding a MARD system skyhook or others seem to have a positive impact on the opening when unstable.

-Michael

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I think that depends on what you call testing. BASE canopies are tested every day in real life situations and not controlled "tests."

Apex are even cutting down on the bulk and weight with the new canopies as they admitted they over engineered it to cope with massive levels of stress.
1338

People aint made of nothin' but water and shit.

Until morale improves, the beatings will continue.

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he question that seemed to be brought up was "are base mains safer than skydiving reserves b/c they are packed more or less the same way as reserves and are (mostly) deployed at the correct altitude, while stable, whereas skydiving reserves are (as was implied) not deployed stable?"



I think the idea that base jumpers always deploy stable is a good example of hubris.

_Am
__

You put the fun in "funnel" - craichead.

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Happened so fast when I cut away I don't think I had time to arch. :D I hesitated on the reserve pull after I cut away,

Put your feet on your ass as you reach for the handles. Push your hips forward at the same time. Pull both handles and then throw your arms back in a classic arch. Nothing to it.:)
Arch as you cutaway, not sfter you cutaway.

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I think that depends on what you call testing. BASE canopies are tested every day in real life situations and not controlled "tests."



I was thinking about it more from the point of view that BASE canopies are typically not opened at terminal, packed with a springloaded PC of skydiving rig size. While I only know the basics of BASE equipment I think the skydiving reserve has been far more extensively tested in our environment.

-Michael

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>>Reserves are engineered and packed to open fast but not so fast they kill you.
I'm glad to see this discussion. Sometimes it seems we avoid talking about it and treat reserves as out of sight - out of mind . . .

I don't believe all that much "engineering" goes into reserve canopies. Reserves are generally garden variety seven cell canopies manufactured by garden variety skydivers who grew up to own parachute manufacturing companies. And they just copied what was already out there. Throw in a new name, a fancy logo, and some splashy marketing and bingo; it's the latest and greatest thing . . .

And your inference that at sub-terminal reserves open crisply, so therefore at terminal they'll open harder is a bit off too. Think it through. Reefing systems (basically the slider) work better at speed. If you open right after a cutaway from an open main it's easier for the reserve to slam the slider down because there's not a lot of relative wind trying to stop the slider from descending. Open a reserve at terminal and the canopy has to fight the high speed relative wind to push the slider down. Ergo - softer opening.

Having been involved in the TSO testing of some new reserves I can say some firms follow the rules of testing religiously and some fudge the crap out of it. But as long as they aren't building anything that is wildly different, or using new exotic materials, the TSO process is just a hoop they need to jump through. In fact if the FAA just hired a wizened old retired master rigger to sit in an office he could inspect these "new" reserves" and just stamp them "same as they ever were" and we could forgo the entire TSO process in most cases. It would make the manufacture, and then the gear itself, less expensive for the end user.

But the real concern for manufacturers is make them small and light weight as that's what the market demands. So the real red meat, when talking about seven cell reserves, is where we go wildly off the rails, and it's all about size.

There are a lot of time bombs on the drop zone. Let's take your average skydiver and call him Johnny Jumper. Johnny weighs, all up and out the door, 180 pounds. Johnny went through AFF like a champ while jumping rather large nine cell student canopies. Johnny loves skydiving, you know, because it changed his life. Tick, tick, tick, tick.

Over the course of the next two years Johnny, who makes good money at his day job, makes a lot of jumps. He loves to free fly and he's worked his way down in main canopy size to a 120 sq-ft main and he's a rather competent swooper. Tick, tick, tick, tick.

But as Johnny went down in main size he also went down in reserve size. His current reserve is now based on a chart he saw in an advertisement and by what his "friends" jump. He's now packing a 126 sq-ft seven cell reserve. He fudged his out the door weight by 4 or 5 pounds, but he's not worried. The chart said this reserve has a "max" weight limit of 254 pounds. So there's no way he'd blow it up or anything. Tick, tick, tick, tick.

The problem is Johnny, who thinks B.A.S.E. jumping is nuts, and CRW isn't such a hot idea either, has never jumped a seven cell canopy in his life. Never mind one this small. Tick, tick, tick, tick.

Then one day Johnny is doing a free fly jump at his regular DZ with his regular friends. Except today they also take along a novice free flyer because Johnny is a good guy. He's even considering becoming an AFF Instructor some day because he likes helping other people out. The dive is going well, except there's a bit of flailing by the novice, but Johnny is smiling, as the novice is learning and trying his best. Then the novice gets a bit a low and Johnnie's attention gets diverted for moment. The novice is trying to transition to a sit but he corks and hits Johnny hard. Johnnies now stunned and his right arm is broken. Tick, tick, tick, tick.

Johnny reaches around both ways and realizes he can't get to his main. So he looks up to clear his airspace, waves off with his one good arm, and then pulls his reserve handle. He's rewarded with a nice straight and soft reserve opening and he breathes a big sigh of relief. The worst is over. Tick, tick, tick, tick.

Johnnie's right arm is killing him. But he focuses in on the task at hand but without thinking too much he reaches up with his good arm and pops his left quickly followed by his right brake. There was a big wobble there but he's flying straight now. Johnny looks up at his reserve. "Man, that’s a huge slider." he thinks. "Am I supposed to stow that or what?" Then his gaze shifts to the canopy itself. It's about the same size as his main, but the shape is funny. Its way boxier looking. Tick, tick, tick, tick.

Johnnie, using his one good arm, and weight shifting in the harness, gets himself in a good spot for landing. He's thinking how lucky he is to be jumping at a big west coast DZ with lots of open fields and not some hole in the woods back east. Johnnie has the wind direction figured out, he knows this won't be a normal landing and he's planning to do a good PLF. He's also going to try and protect his bad arm as much as possible. Tick, tick, tick, tick.

At 150-feet it's going well. And he's got both toggles in his one good hand. "Gee," Johnny sees, "I'm going kinda fast here." So he pulls down on the toggles a bit more. Then a gust of wind hits him from the side and he starts turning. He tries to drop one toggle to correct the turn but just manages to drop both. While reaching up to recapture at least the one toggle Johnny crashes into the ground not being ready for it. And he breaks his right leg in two places. Tick, tick, tick, tick. BOOM!

Johnny's dream career as a weekend skydiving Instructor are over. And for the rest of his life he'll suffer the effects of this day. His family showers him with affection and care, but they throw in a heaping helping of, "I told you so." And Johnny quits skydiving. In his golden years Johnny can’t do much because of the crippling arthritis that set into his arm and leg that never healed right. Johnny (everyone calls him John now) dies of natural causes in front of the TV . . .

NickD :)

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Good post Nick!
I brought up a proposal once at the DZ to have all sorts of reserve demo canopies available to fly.
We have thousands of jumpers out there that have never flown a 7 cell, nor do they have a clue how their reserve will fly or flare. I have seen a lot of reserve riders crash and burn over the years.
Most jumpers don't have a clue as to what size reserve they even have in their rig, or what color it is!
Talk to your riggers folks. Ask them what the characterisitcs of your reserve are.
There's nothing like being over a bunch of obstacles under a never flown reserve, Murphy's Law at it's finest hour!

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>The problem is Johnny, who thinks B.A.S.E. jumping is nuts, and
>CRW isn't such a hot idea either, has never jumped a seven cell canopy
>in his life. Never mind one this small.

This is indeed a big problem. Some encouraging signs that I see are:

1) the slow phaseout of Super Ravens. All 7-cells fly differently than 9-cells, but overloaded Ravens are the worst of the bunch when it comes to landings. I have seen several injuries caused by people stalling their Micro Ravens on landing. (In defense of Precision the R-Max does not have this problem.)

2) the gradually increasing availability of larger containers for reserves. I just got a Mirage sized for a 109 main and a 143 reserve; I figure I am unlikely to ever look up at my reserve and think "damn, that thing's too big!"

3) the availability of smaller pack volume reserves. Johnny may never give up his Super RSTXKIII Ultra Tiny rig, but not aw least he can fit one size larger Optimum in it without having to jump a "dorky" bigger rig.

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Thanks, Nick.

Like above, good post.

Swooping a landing and actually flaring at the point you intend to hit are two different sytles of canopy control.

Guys & Gals, jump a 7 cell before you HAVE to jump a 7 cell. Talk to the old timers and CRW Dogs about the difference. Then go out and do it.

BTW, for GP learn to PLF. (If any of these abbreviations confuse you, just read the above and do it) ;)

____________________________________
I'm back in the USA!!

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I was thinking about it more from the point of view that BASE canopies are typically not opened at terminal



It entirely depends on the jumper and the area -- e.g. if you live near Norway, you might do lots of terminal jumps from the large objects there. Of course, the rig is configured differently for such jumps -- perhaps different canopy, but certainly different slider and pilot chute than a 0- or 2-second delay jump.
Looking for newbie rig, all components...

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Good read nick.

One thing I've pointed out a number of times before is that it's also important to keep the main and reserve somewhat close because they're well behaved if you happen to have 2 out ie low pull & AAD fire.

I flew my PD160R once and was kinda surprised that it appeared to fly much quicker. I wonder if the flare you get is more characteristic of the design or the fact it's F111. I know reserves have very low porosity compared to ragged out old student canopies.

-Michael

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>>Reserves are engineered and packed to open fast but not so fast they kill you.<<

And your inference that at sub-terminal reserves open crisply, so therefore at terminal they'll open harder is a bit off too. Think it through. Reefing systems (basically the slider) work better at speed. If you open right after a cutaway from an open main it's easier for the reserve to slam the slider down because there's not a lot of relative wind trying to stop the slider from descending. Open a reserve at terminal and the canopy has to fight the high speed relative wind to push the slider down. Ergo - softer opening.



I should have completed my thought better there. You covered some in your post but I'll try to put what I should have said...

Our reserves are designed to open fast enough at sub-terminal and slow enough at terminal. I am not convinced that these BASE canopies with their mesh sliders are tested as well as a skydiving reserve. My 2 subterminal reserve rides were open in about 300'. From what I understand in a number of BASE situations you go splat around the 300' mark.

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>Open a reserve at terminal and the canopy has to fight the high
>speed relative wind to push the slider down. Ergo - softer opening.

But that's just one factor.

Another factor - spreading force. A canopy at terminal is going to generate a lot more lateral force on the lines, trying to spread them out. This is resisted by the slider, but the faster you go, the more force there is trying to get the slider down.

Then there's the relationship between time and deceleration. A 2 second opening at 60mph is pretty soft; a 2 second opening at 120mph is a lot harder.

Then there's slider friction, which is dependent on type of grommets, spreading force and type of line. And then there's slider inertia; heavier grommets on a slider can exacerbate hard openings. There are brake settings, line type, trim issues, half a dozen others.

And then, of course, you have the issue that this doesn't scale with altitude or size. Take a 230 sq ft canopy that opens great and scale it down linearly to a 120 sq ft canopy and its openings will be completely different. Open it at 8000 feet instead of 3000 feet and you've got a different set of forces acting at a different speed, and you're likely to see a harder opening.

What's amazing is that this relatively simple system actually does OK when presented with this wide range of variables. We tend to remember the few times that it doesn't all work out, but it's really pretty remarkable that a piece of fabric with four holes in it often does as good a job (if not a better job) than systems of ropes and rings, hydraulics and even timed pyrotechnic cutters on reefing lines.

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