Deliberate Malfunctions

[Smeger 0]

When a new parachute is designed and tested, how do they test them? Does someone deliberately try to mal or do they just jump that chute X many times and let the chute mal itself?
(If that makes sense to you, I'll get the next round lol)

I know that in paragliding, they deliberetly try to stall the wing to see how it recovers, just wondered if the same process is used in skydiving?

(If at first you don't succeed, skydiving isn't for you)

[speedy 0]

I watched them testing a new tandem reserve on TV once,
They chucked a metal dummy out of the plane with cypres.

Dave

Fallschirmsport Marl

[Yossarian 0]

i thought they just did intentional cutaways, wore three rigs, i saw some old pics of a normal rig (the test main in it and a reserve) and also a belly mounted reserve. cant imagine they still have belly mounted round reserves though

[sid 1]

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i thought they just did intentional cutaways, wore three rigs, i saw some old pics of a normal rig (the test main in it and a reserve) and also a belly mounted reserve. cant imagine they still have belly mounted round reserves though

Yes we do! We have double cutaway rigs and usually the front mounted reserve is a round. Initial tests are usually drop tests with a dummy if there are major design changes. Otherwise we just go out and test'em. Adds a whole new element to the sport....

Pete Draper,

Just because my life plan is written on the back of a Hooter's Napkin, it's still a life plan.... right?

[riggerrob 643]

Sort of .....
Standards for reserves are far tighter than for mains.

When testing new mains, PD never lands a prototype on the first jump. Generally, they start with a few 12 grand hop-and-pops, but they plan on cutting away before 3,000' and deploying a reliable main.
First phase testing explores: opening time, opening shock, opening heading, flight with brakes stowed, what happens when you release the brakes, gentle braked turns, vigorously braked turns, stalls, spirals, and a variety of landing techniques.
Over the course of hundreds of jumps, test jumpers explore all the corners of the envelope, including a few that they never want to see customers in: for example, seriously over-loading.

Then, during the beta testing phase, they give a handful of pre-production models to a high-ranking competition team. The team makes a thousand or more jumps - before the next world meet - and in the process uncovers longer-term durability issues. That is the primary reason that gold-medal athletes get free gear.

TSO certification tests for reserves are far more formalized. We usually start with structural tests - usually from 300 feet with instrumented rubber dummies. If the design survives the structural over-load tests, then we progress to line-twists, freezing and baking tests, followed by a series of manned tests to confirm opening times, reliability, rate of descent, turn rate, etc.
TSO-C23D requires 70-some-odd drop tests in a variety of scenarios. What with all the (rubber) dummies, instrumentation, fancy airplanes (B-25, CASA, etc.), senior personnel, travel expenses, etc. each drop can easily cost $800, which drives the price of a TSO series of drop tests into the $56,000 range. Is it any wonder that so few radically new reserves are introduce?

Oh, and deliberately packing malfunctions does not teach you anything about the new design. It only reminds you that a bad enough packer can make ANY parachute malfunction.

[Smeger 0]

Thanks very much, thats definitely answered my question. I didn't realise it was that extensive in testing, very reassuring.

Thanks again!

[labrys 0]

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Oh, and deliberately packing malfunctions does not teach you anything about the new design. It only reminds you that a bad enough packer can make ANY parachute malfunction.

Out of curiousity, would deliberately packing a line twist or 2 or an unstowed toggle provide any insight about how tolerant a new design was of those particular (common / borderline) mals? Or do those conditions happen often enough by chance during testing to make it a mute point?

Owned by Remi #?

[packerboy 3]

I would hope that people who design, build, test, manufacture, sell, and repair our reserve parachutes aren't the type that would accidently pack something w/ an unstowed toggle. But shit happens probably although they may not advertise it on a public forum. Even NASA fucks up.

--------------------------------------------------
In matters of style, swim with the current; in matters of principle, stand like a rock. ~ Thomas Jefferson

[labrys 0]

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I would hope that people who design, build, test, manufacture, sell, and repair our reserve parachutes aren't the type that would accidently pack something w/ an unstowed toggle.

I wasn't trying to knock anyone.

Toggles come unstowed for more reasons than packing errors. I've had riser flaps dislodge a toggle a few times during deployment. Flukes happen.

Owned by Remi #?

[brianfry713 0]

You could always pack yourself a step through to make it more interesting. Or, to make it really fun, release one riser (not the RSL one of course). For one more, try hooking the canopy up backwards or with a twist in a riser. Or hook up the lines randomly to different risers. You can wrap your steering lines through different lines, or cross each one to the wrong side. Try passing the P/C through different lines and see what happens. Switch the left and right risers. I'm sure there's more .

Edit to add: One more, try tying your toggles in knots and try to get them out, or disconnect one and land on rear risers.

Of course, I'm only listing possible packing errors, don't try any of these unless you know what you're doing.

BASE 1224, Senior Parachute Rigger, CPL ASEL IA, AGI, IGI
USPA Coach & UPT Tandem Instructor, PRO, Altimaster Field Support Representative

[sundevil777 102]

All very interesting, but some of your suggestions are likely to damage a canopy.

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

[sundevil777 102]

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Toggles come unstowed for more reasons than packing errors. I've had riser flaps dislodge a toggle a few times during deployment. Flukes happen.

I've never been able to understand why toggles come unstowed so often. It has never happened to me, and my first 1000 jumps were with old style toggles that had no hood for the nose, only velcro to hold it down, and no riser covers.

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

[chachi 0]

get the xaos boyz video. it has many of the test jumps for the R-MAX.

best part, not many third canopies present :o

[JohnMitchell 16]

Just food for thought. There are FAA standards for the harness and reserves, but absolutely none for main canopies. If you wanted to tie clothesline onto an old bedsheet and pack it up for your main, it would be 100% legal. Probably wouldn't flare very well.
Just another example of how legal doesn't always mean safe, and safe ain't neccessarily always legal. It's good that the system doesn't try to "insure" everything. It's nice to have a little room to experiment.

[JohnMitchell 16]

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best part, not many third canopies present :o

<<<>>>>>>

[firstime 0]

great post Rob,
I was impressed with your info. We as a community should appreciate what ppl do to ensure our well being.

hats off to the unsung heroes

[HeatherB 0]

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I've never been able to understand why toggles come unstowed so often. It has never happened to me, and my first 1000 jumps were with old style toggles that had no hood for the nose, only velcro to hold it down, and no riser covers.

I don't get it either. I've never had a brake fire.

I'm wondering if it happens more on certain containers vs others. Hmmm.

[Capt36 6]

Mighty fine answer!...Errr... answers..many answers..very good!

Practice random acts of kindness, and senseless beauty...

And, give money for Mr Douglas! www.mrdouglas.org

[riggerrob 643]

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I've never been able to understand why toggles come unstowed so often. It has never happened to me, and my first 1000 jumps were with old style toggles that had no hood for the nose, only velcro to hold it down, and no riser covers.

I don't get it either. I've never had a brake fire.

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Many brake fires are caused by packers fixating on a minor point (hood), but ignoring a major point (pulling cat's eye BELOW) guide ring.

One of the joys of more sophisticated gear!
BWAHAHAHAHAH!

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[karenmeal 0]

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Many brake fires are caused by packers

Probably more likely they are caused by the people who can hardly pack for themselves because the packers always help them out. So I guess in a way it would be packers causing it..

Whats with the packer hate?

"Life is a temporary victory over the causes which induce death." - Sylvester Graham

[NWFlyer 2]

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Many brake fires are caused by packers

Probably more likely they are caused by the people who can hardly pack for themselves because the packers always help them out. So I guess in a way it would be packers causing it..

Whats with the packer hate?

In his defense, "packer" in this case could mean whoever packed the rig, whether it was the jumper or a paid packer. I wasn't reading "packer hate" into that.

Unfortunately, though, not all packers (whether they be folks who earn money packing for others or people who pack their own rigs) are as conscientious as you. Rob's response helped to remind me what would normally be the cause of a brake fire.

[Andy9o8 2]

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Whats with the packer hate?

You know, if you marinate packer overnight in Italian dressing, it tastes much like chicken.

[kschilk 0]

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i thought they just did intentional cutaways, wore three rigs, i saw some old pics of a normal rig (the test main in it and a reserve) and also a belly mounted reserve. cant imagine they still have belly mounted round reserves though

In 2000, I jumped with a belly reserve. I think it was slightly dated, though....it had a 10 inch steak knife attached to it, by a bungee cord.

"T'was ever thus."

[kschilk 0]

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Whats with the packer hate?

Awwwww.....Green Bay's ok!

"T'was ever thus."

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[HeatherB 0]

Am I the only crazy person here who does the following if using a packer:

I stow my brakes (right after landing, as I always do)

I unstow my slider

I cock my pilot chute

I do a line check.

I even check out my safety line and bridle to make sure they aren't all twisted up. (that's really just to be nice and save the packer a little time)

After it is packed, I check the pins, PC, and all that jazz.

Call me paranoid.

If I didn't do the above, I'd be wondering in the plane about what kind of opening I was about to have.

Of course, I used to be packer-dependent. I hated packing. But I was very good last year about packing my own and I switched from being worried about my pack jobs to being worried about paid pack jobs.

I can understand that team members who are doing back-to-backs do not have the time to take care of those things, but don't casual jumpers do at least some of the above?