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JaapSuter

Pie Slice Pilotchutes

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I was thinking that PC oscillation is a problem, and as far as I’ve understood, PC oscillation is believed to be a main cause for offheading when everything else is done right (good body position, no winds, good packing, canopy doesn’t snag on the tray).

But you have a good point: How often does this actually lead to an offheading more than, say +/- 60 degrees? 1:100, 1:1000? I guess it’s a personal decision what odds are ok, if we’re ever able to say what the odds are.

And I agree that cost and cost vs. added benefit may in practise be showstoppers, but we won’t know that before we know what the improved design is (if one exists).

So why look for a new design if we don’t know how big of a problem PC oscillation actually is? How would we verify the new design? How many jumps would it take? How about all the other factors that affect heading? Sounds like we would need a lab set-up. A new design may introduce new unforeseen problems…

But then again, how many of the modifications that have been done sofar are based on solid numbers? I think most of them are based on subjective observations and good ideas. I mean, how much evidence do we have that snagging on the corners of the pack tray is a problem? (With wingsuit, just arch before deployment. If you have head-down deployment, what are the odds of offheading more than +/- 60 degrees due to the canopy snagging on the corners?) But I like the _idea_ of dynamic corners. (no disrespect towards the manufacturers here, I think this a part of the sport)

Anyone have an opinion of what the odds are that PC oscillation alone will result in an offheading of more than +/-60 degrees, using a vented ZP PC?
Anyone who likes the idea of a PC less prone to oscillations?

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I was thinking that PC oscillation is a problem, and as far as I’ve understood, PC oscillation is believed to be a main cause for offheading when everything else is done right (good body position, no winds, good packing, canopy doesn’t snag on the tray).



"when everthing else is done right."

I think you'd get better results convincing people to get better at the those other factors you mentioned. too many want the easy way out and choose not to put effort into what they CAN do.

as you mentioned, if you can't quantify the problem, you'll never be able to judge that a fix works.

as for me, redesign the pc. go for it. but I'd rather see people focused on what is killing people.
DON'T PANIC
The lies in learning how to throw yourself at the ground and miss.
sloppy habits -> sloppy jumps -> injury or worse

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The only camera I have currently available is a phone. The lighting isn't great in here either so pardon the fantastic quality.

Asylum Toxic Pilot chute Pictures:

Note the single point attachment. It allows for zero tolerance trim and easily centered bridle attachment.

The vents are made with marquisette mesh (fine mesh)

From skirt to apex, the canopy material will not stretch. After it inflates, as much as ZP stretches, will stretch uniformly outward.

The design seems really nice. The workmanship is excellent.

After august I can give a review. I should have a bunch of daytime jumps on it by then so hopefully there will be good video and pictures of how it performs. It's worked every time so far, so the reviews up to this point are great.

(If the single point attachment picture doesn't open, save it first.)

My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto

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Is that the newer version of the bridle attachment point, which has the loop made out of an extension of the apex-pull-down-line?

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Yes it is.
My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto

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I should have a bunch of daytime jumps on it by then so hopefully there will be good video and pictures of how it performs.



I've got three of them in use for FJC's, so I've got a pretty large collection of daytime video if you want to see it.
-- Tom Aiello

[email protected]
SnakeRiverBASE.com

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Oh sorry. I meant 24 feet! :D:D:D
Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174

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It's about time someone that has a Toxic or a few mentions it.

Any opinions yet?
My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto

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First of all, Yuri you have way too much time on your hands!

I guess I wonder if it matters so much, the oscillation that is, because by the time there is enough resonance, that is right at or a split second after line stretch, your center cell has been presented to the air... that is your heading has most likely already been established...

I don't think all this mental masturbation will result in better PCs or less off headings.

I'm with Ray on this one...

T.

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I don't think all this mental masturbation will result in better PCs or less off headings.



You say that like masturbation was a bad thing.

:PMichael

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I don't think all this mental masturbation will result in better PCs or less off headings.



I can say for certain that not thinking about the gear is extremely unlikely to improve the gear.

To borrow from another thread: our greatest defense is that squishy thing inside our helmets--especially using it before committing to the jump.
-- Tom Aiello

[email protected]
SnakeRiverBASE.com

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I don't think all this mental masturbation will result in better PCs or less off headings.



You say that like masturbation was a bad thing.:P



When I step off the edge, I feel overwhelmed with the gratitude to the Founding Monkeys who started mental masturbation 30,000 years ago. :)
Android+Wear/iOS/Windows apps:
L/D Vario, Smart Altimeter, Rockdrop Pro, Wingsuit FAP
iOS only: L/D Magic
Windows only: WS Studio

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Still trying to figure out what's wrong with F111. Why is F111 looked down upon? From a manufacturers standpoint it's the simplest and least expensive to construct. From a jumpers standpoint you get unparalleled sub terminal slider up performance and it costs less – you don’t have to spend money on injuries or funerals anymore and you have more money to spend on traveling.

Vented ZP is acceptable for slider down because the p/c does not have a chance to oscillate enough to influence the canopy extraction and thus the opening direction. Vents on a ZP p/c clearly DO NOT eliminate sub terminal p/c oscillation - only reduces it 10 to 20% over non-vented. F111 DOES eliminate ALL p/c oscillation. In other words, non-vented and vented ZP !SUCKS! for sub terminal slider up! Make sense?

F111 being thought of as being too porous and therefore taking too long to inflate can be, and has been, proven fallacious by a simple spring-loaded test like TA has done. Give F111 a try...you will not be disappointed. Or stay on the vented p/c bandwagon for sub-terminal slider up until you hit a wall and break a foot, ankle, leg (and feel the effects FOR THE REST OF YOUR LIFE) or die. Good luck!

The Death Monger

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I can say for certain that not thinking about the gear is extremely unlikely to improve the gear.

To borrow from another thread: our greatest defense is that squishy thing inside our helmets--especially using it before committing to the jump.



while I am NOT convinced this style of pc will make a significant difference, Tom is correct. there is no harm in trying.

more importantly, kudo's to Marty. those pc's are works of art! keeping everything symmetrical and balanced must not be easy, or quick.
DON'T PANIC
The lies in learning how to throw yourself at the ground and miss.
sloppy habits -> sloppy jumps -> injury or worse

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hehe.. why you pickn on me luv2fly? ;) Yeah, I know, you're speaking all of us.

I personally have nothing against F-111. I also don't have any pilot chutes made from it. When I Purchased my first new rig, I bought a bunch of pilot chutes to go with it and still use them.

I bought the Toxic because it's very nice and the quality is supreme. The one pilot chute I still have that's not CR/Asylum is not symetrical (which on this PC is not a big deal). It's also not the size it's labled. The centerline was replaced by me because the original was made way too short by approximately 3 inches.

It's still fine for objects in the 0-1 second delay range, I'll continue to use on back to back loads.

As for F-111 being too porous, no, I don't believe that. It's definately not the case.

I've seen the drop tests on F-111 and ZP pilot chutes that were built the same and sure enough the F-111 was a lot more stable. We agree because it would be foolish not too. There's absolute evidence in captured on the videos.

If the PC's don't kill me, I'll show you video at the beginning of next month on how my 38s perform in the 5 second range.
My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto

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from those who jump them, i've heard that the toxic is getting approx. 60-80 ft. faster than normal vented pc's.

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from those who jump them, i've heard that the toxic is getting approx. 60-80 ft. faster than normal vented pc's.



Oh, that’s probably a slight exaggeration. It's roughly half to more than half the distance of a normal slider off deployment.
My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto

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how long do you think it takes for a normal slider off opening?

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Hi

I would like to know what gear configuration (container, canopy, PC size) and delay your observations are based on.

Would you say the faster extraction to linestretch is due to a quicker inflation or more drag, or both?

What size Toxic are you comparing to what size and type of normal PC?

I have video of a jump with a 46"AV PC, using my Blackjack 260 in a Paratech Odyssey FX.
I went stowed and did pretty much a drop-and-throw (it was from a lowish Tyrolean Traverse).

From the ground video you can clearly see my PC gets the container open before it has enough drag to lift the 260 out of the packtray (it has dynamic corners, so there is nothing holding the canopy in other than the flaps and pins/loops).

So for a higher extraction in that case the PC would not only have to inflate quicker, but have significantly more drag also.

thanks!
sam

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from those who jump them, i've heard that the toxic is getting approx. 60-80 ft. faster than normal vented pc's.



Wow!

That's not at all my experience, based on around 100 jumps made on my 3 toxics over the past 2 months.
-- Tom Aiello

[email protected]
SnakeRiverBASE.com

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So for a higher extraction in that case the PC would not only have to inflate quicker, but have significantly more drag also.



I think the Toxics do have higher drag (allowing you, incidentally, to use a smaller PC size for a given task, and thereby reduce your chance of hesitation). I'm not so convinced that they inflate faster. More consistently, perhaps, but not overall faster.
-- Tom Aiello

[email protected]
SnakeRiverBASE.com

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