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d_goldsmith

PC Oscillation Theory

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pcs wont oscilliate if u let Jesus into your heart




Jesus won't get into your heart if you can keep your PC's from oscillating.

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What if Jesus created the perfect PC? Then would you let him in your heart?
Leroy


..I knew I was an unwanted baby when I saw my bath toys were a toaster and a radio...

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Jesus was offered a chance to do a BASE jump, but he rejected it. Apparently, he was afraid his PC would oscillate and cause 180.

Unlike him, we follow Satan's words without hesitation!










(ok, written after a couple of beers, take it easy ;))
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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I wonder how many BASE Jumpers are athiest, agnostisc, or otherwise?
Leroy


..I knew I was an unwanted baby when I saw my bath toys were a toaster and a radio...

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I am a Christian.
==================================

I've got all I need, Jesus and gravity. Dolly Parton

http://www.AveryBadenhop.com

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I'm an agnostic atheist. I think all the mass and energy in the universe is tied togethor and is something special and even spiritual like a god, but I don't think that "god" has a conscience.
I've got this really hardcore group of gaurdian angels that need a free paid vacation.
~Dan Osman

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yuri base : ... " Unlike him, we follow Satan's words without hesitation ! "
D goldsmith : ... " spiritual like a god, but I don't think that "god" has a conscience. "
_____

Yes but chances are, Even God knows to at Least make a ' Conscience' effort to throw a Pilot chute without ' Hesitation' .

When I go-in BASE jumping and God lets me into Heaven. First thing I'm going to do is run over to Buda and ask him the age old philosophical question of.
If a BASE jumper Crates-In leaving body parts all over the Talus and No One is there to hear it. Does it make a sound ?
.
.

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GIVE IT UP TO GOD!!!

The PC Oscillation problem must be solved to reduce the injury and death we see in BASE. I've put lots of energy into this problem. Given that I have not BASEd in 3 years 4 months..since losing my friend DW at RG in 2003. I may be off a bit in my explanation so please correct me if you see a mistake in my understanding here...but it amuses me that nothing has advanced in this area in years! And it keeps coming back as a problem...Every so often I say my .02 cents again and then it goes away until some new observation comes from someone different...

To explain where I'm coming from...I'll start at the beginning (as far as I can remember it). Anne Helliwell and Todd Shoebothom from BR were the first to introduce me to the idea of production and use of F111 PCs in BASE. I used the F111 for a couple years and later discarded it as not as "bullet proof" as ZP. I got some PC insight from SpACE whilst hanging out in Norway but still did not understand the whole concept. Then came the vented ZP and this supposedly was the "Godsend" of PC safety...and everyone tried to grab a bit of the market share of the ultimate PC - a vented ZP. BUT, I began to see this as a micromental improvement over regular ZP because the damn PC was still oscillating and killing.

It was at this point that Anne and I looked for an explanation to the problem and we searched for a solution. As soon as a ZP PC reached full bridle stretch in non-terminal jumps (mostly sub-terminal slider up), it was more likely to meet the air with a reaction to the action and begin the oscillation. We tested and researched the vented ZP PC on balloon drops with a weight to replicate a 4 second delay and the results were as expected. The vented ZP PC was a hoax...a great way to market a "revolutionary idea." But, without the desired outcome - a significant reduction in oscillation. It was only a minor one - maybe 10% - but not enough testing was done.

Anne did great camera work in Malaysia - recording more than 800 jumps made over 2 years. From this work we saw that of my 23 jumps in 2002/2003, I did not have one PC oscillation beyond about 5 degrees from center while the regular ZP PC and vented ZP PC saw about a 20% chance of severe oscillation leading to offheadings - sometimes up to 45 degrees - swirling around and around. This convinced me that F111 was the true "Godsend" - whatever that means - and ZP PCs with or without vents was a hoax.

Think of a F111 PC as a PC with thousands of vents distributed equally. That's the best way to look at it and it's truly the best way to eliminate offheading openings attributed to PC action (with current technology).

That is all. Be smart and live longer without injury - stop using a ZP PC for subterminal slider up jumping!

Good luck!
JJ

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Does that only apply to sub-terminal slider up? If so, why?

Edit to add: I'm guessing you don't have as much data on sub-terminal slider down and terminal, but does anyone else have data about those types of jumps with f111 compared to zp vented?
I've got this really hardcore group of gaurdian angels that need a free paid vacation.
~Dan Osman

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GIVE IT UP TO GOD!!!

The PC Oscillation problem must be solved to reduce the injury and death we see in BASE. I've put lots of energy into this problem. Given that I have not BASEd in 3 years 4 months..since losing my friend DW at RG in 2003. I may be off a bit in my explanation so please correct me if you see a mistake in my understanding here...but it amuses me that nothing has advanced in this area in years! And it keeps coming back as a problem...Every so often I say my .02 cents again and then it goes away until some new observation comes from someone different...

To explain where I'm coming from...I'll start at the beginning (as far as I can remember it). Anne Helliwell and Todd Shoebothom from BR were the first to introduce me to the idea of production and use of F111 PCs in BASE. I used the F111 for a couple years and later discarded it as not as "bullet proof" as ZP. I got some PC insight from SpACE whilst hanging out in Norway but still did not understand the whole concept. Then came the vented ZP and this supposedly was the "Godsend" of PC safety...and everyone tried to grab a bit of the market share of the ultimate PC - a vented ZP. BUT, I began to see this as a micromental improvement over regular ZP because the damn PC was still oscillating and killing.

It was at this point that Anne and I looked for an explanation to the problem and we searched for a solution. As soon as a ZP PC reached full bridle stretch in non-terminal jumps (mostly sub-terminal slider up), it was more likely to meet the air with a reaction to the action and begin the oscillation. We tested and researched the vented ZP PC on balloon drops with a weight to replicate a 4 second delay and the results were as expected. The vented ZP PC was a hoax...a great way to market a "revolutionary idea." But, without the desired outcome - a significant reduction in oscillation. It was only a minor one - maybe 10% - but not enough testing was done.

Anne did great camera work in Malaysia - recording more than 800 jumps made over 2 years. From this work we saw that of my 23 jumps in 2002/2003, I did not have one PC oscillation beyond about 5 degrees from center while the regular ZP PC and vented ZP PC saw about a 20% chance of severe oscillation leading to offheadings - sometimes up to 45 degrees - swirling around and around. This convinced me that F111 was the true "Godsend" - whatever that means - and ZP PCs with or without vents was a hoax.

Think of a F111 PC as a PC with thousands of vents distributed equally. That's the best way to look at it and it's truly the best way to eliminate offheading openings attributed to PC action (with current technology).

That is all. Be smart and live longer without injury - stop using a ZP PC for subterminal slider up jumping!

Good luck!
JJ


good post.

I also prefer an F-111 for not only slider up in the 4-6 sec delay range but also terminal jumps as well for the very reason you explained. How do you feel about using F-111 on slider up jumps at the idaho bridge? How would you feel about everyone else using F-111 there?

One thing jumpers should keep in mind if using F-111 is that the porosity will degrade much faster than with ZP. Perhaps that's what you meant by "not as 'bullet proof' as ZP." As much as I do like F-111 PCs for some types of jumps I personally would not want to jump a clapped out one. What are your experiences and thoughs about a tired F-111 PC? Is there an exit altitude where you would not want to use F-111?
Life is like a box of chocolates.

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One thing jumpers should keep in mind if using F-111 is that the porosity will degrade much faster than with ZP. Perhaps that's what you meant by "not as 'bullet proof' as ZP."



I prefer F111 also and will use a new PC after 100 jumps. How many jumps would you kids put on a F111 PC before replacing it?

Those who do, can't explain. Those who don't, can't understand.

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How do you feel about using F-111 on slider up jumps at the idaho bridge? How would you feel about everyone else using F-111 there?



I have several F-111 PC's in service for FJC's here. I've been pleased with their performance (I think they oscillate noticeably less than even the best vented ZP PC's I'm using). I replace the F-111 PC's approximately every 100 jumps.

At some point I'll try to sit down and edit out all the video from my FJC's, to compare PC's, as Annie did at the events in Malaysia. The short version, though, is that I agree with her conclusions. F-111 PC's are an excellent tool, and are usually vastly underrated by modern BASE jumpers.

I don't think I'd mind if everyone used F-111 here, provided they were careful about maintenance (and replacement).
-- Tom Aiello

[email protected]
SnakeRiverBASE.com

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Just an additional observation.

In addition to damping PC oscillation better than ZP, the F-111 PC's actually start with less oscillation. This is because of the typical inflation patterns. From observation, the ZP PC's will inflate when they reach bridle stretch out to one side of the jumper (which means that they have a "pendulum" swing to start the oscillation). The F-111 will actually swing up and over (directly above) the jumper, and _then_ inflate (eliminating that initial "pendulum" into position).
-- Tom Aiello

[email protected]
SnakeRiverBASE.com

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Im sure it has been brought up before... and maybe not.

I dont think pc swings are caused by 'air spilling out one side', granted, that is what is happening to some extent, but i think the PC is acting like a foil itself, and actualy 'gliding' in the circle above the jumper, much like a wing on a kite.

but, i dont know.
just a thought.

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TO answer your questions BASEjumper I had about 150 jumps on a 36" F111 - mostly terminal and it still worked fine...(but I gave it to someone when I sold him a canopy - and he continued to use it - not sure how many jumps tho). I have used F111 (not clapped out) on 160' freefall jumps with no noticeable problems or differences. But yes, F111 when exposed to water and more then 100 jumps will degrade to the point where I wouldn't want to personally use one but wouldn't mind if you did...clearly for testing purposes only tho...

I would ALWAYS use F111 on sub-terminal and terminal jumps. Sometimes I used ZP on slider down mostly because I don't think in no wind conditions (what I mostly liked to jump in) there was clearly not a difference between F111 and ZP.

I can't stress this enough! Use F111 - especially for sub-terminal slider up! That is, if you want to live injury/fatality free...
Hope this helps!
JJ

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Hi,

just want to post this attachement again. It contains some thoughts about pcs, too.

I wrote this a while ago after years of own research. I checked it once in a while and updated new thoughts. So I don't know if it is a wise document. It's just a point of view.
I'm this way not overly concerned but it seems basic stuff gets lost quicker and quicker.

feel free to read it

my 2 cents
M.

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