Bungy Pilotchute

[TimHurford 0]

This got buried in another thread.

Bungy pilot chutes. The bungy connects the apex to the base so that in the normal state the PC is 'collapsed'. Right?

The pressure from deployment of the PC stretches the bungy, inflates the PC, extracts the bag; when the canopy is inflated and the pressure on the PC is reduced, the PC returns to the collapsed state?

So what happens when the bungy wears out?

Does it stretch so that the PC is always 'inflated'? Or does it loose elasticity so that the PC can't inflate? Or is it a combination so that the PC only partially inflates?

[mr2mk1g 10]

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So what happens when the bungy wears out?

you replace it

(if its worn out, it will not have the elastic strength to collapse the pilot chute, so worst case scenario is the PC is always un-collapsed.)

[councilman24 37]

If the bungee breaks your left with a non collapsing PC. When it wears out it becomes weaker and allows the PC to inflate easier. The real trick with these is setting the bungee tight enough to keep the PC collapsed under canopy but inflate on low speed deployments. This is a balancing act. At my small DZ we have one very experience jumper who uses one. He flies a medium performance canopy and hasn't had any problem with it. If you doing a lot of SL jumpmaster hop and pops or low exit demo's with a high performance canopy this probably isn't a good choice. The obvious advantage is that it doesn't require cocking, which may have been the initial problem with the recent Australian fatality.

I'm old for my age.
Terry Urban
D-8631
FAA DPRE

[piisfish 140]

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(if its worn out, it will not have the elastic strength to collapse the pilot chute, so worst case scenario is the PC is always un-collapsed.)

he just said it...

scissors beat paper, paper beat rock, rock beat wingsuit - KarlM

[mjosparky 4]

Not true, any bungy pilotchute that will not inflate during C&P speeds is not made right. I do C&P's at demos all the time with out any problem. Some are from a Wilga which flies jump run at 65 mph. I build my own and have run several tests on them. They open at 40/42 mph on a steady pull and 33/35 on snatch pull.
Sparky

My idea of a fair fight is clubbing baby seals

[councilman24 37]

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Not true, any bungy pilotchute that will not inflate during C&P speeds is not made right. I do C&P's at demos all the time with out any problem. Some are from a Wilga which flies jump run at 65 mph. I build my own and have run several tests on them. They open at 40/42 mph on a steady pull and 33/35 on snatch pull.
Sparky

I agree. You missed my point. I said using one with a HIGH performance canopy may not be the best choice. When canopies are landing at 80 mph that means it will be inflating then too.

I'm old for my age.
Terry Urban
D-8631
FAA DPRE

[ACMESkydiver 0]

Sparky I was thinking about maybe getting a bungy PC for my rig when it comes in...I'm just freaked about forgeting to cock a PC.... I did read where a bungy PC can take a sec or 2 extra during sub-terminal deploys...you're saying here that isn't a problem. Good to know...

What about jumping from a balloon? How about that? If you hopped and popped from a balloon...would it be a problem?

And if ya don't mind (PM if you want) can you let me know where you got your bungy PC from/manufacturer?

Thanks!

~Jaye
Do not believe that possibly you can escape the reward of your action.

[mjosparky 4]

Terry,
You are right, I did miss your point. My bad. And you are correct, it will inflate during high speed maneuvers under a high performance canopy.
Sparky

My idea of a fair fight is clubbing baby seals

[mjosparky 4]

PM sent.
Sparky

My idea of a fair fight is clubbing baby seals

[scottjaco 0]

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What about jumping from a balloon? How about that? If you hopped and popped from a balloon...would it be a problem?

Well, think about physics....

With a kill line, the pilot chute is already open when you pitch out. It catches air immediatly.

With bungie, it may take a few extra nano seconds for the air to streatch the bungee and allow air to inflate the pilot chute.

I had my bungee converted to a kill line when I first bought my rig based on this principal.

In theory, Kill line is better.

edited to add: why are you so afraid you'll forget to cock it? you know about the green indicator window on the bridle near you closing pin right?

[jrcrackers 0]

with the advent of better technology, why use old outdated methods. Get rid of it

[alan 1]

Awww crap. I just posted answers to all of your questions in the other thread.

alan

[ACMESkydiver 0]

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edited to add: why are you so afraid you'll forget to cock it? you know about the green indicator window on the bridle near you closing pin right?

...just don't like to play into Murphy's Law, that's all... ...and the recent events with non-cocked PC's has me a lil' edgey.

~Jaye
Do not believe that possibly you can escape the reward of your action.

[jerry81 10]

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edited to add: why are you so afraid you'll forget to cock it? you know about the green indicator window on the bridle near you closing pin right?

...just don't like to play into Murphy's Law, that's all... ...and the recent events with non-cocked PC's has me a lil' edgey.

I think you're not giving yourself enough credit. Cocking the pc is simply an integral part of packing- if you remember to stow the brakes, uncollapse the slider and pull the pull-up cord from the closing loop, you can probably safely assume you won't forget to cock the pc, either.
Personally, I'd find it harder to trust a pc that is collapsed when it leaves my hand...not to mention the hop&pop hesitation stories floating around.

---

[rainman 0]

I have a bungy collapsible pilot on my rig that can be 'cocked' as well.

I find it a bit hard to describe, but the bungy is attached to the bridle 3-4 inches from the bottom (mesh) of the pilot. Right next to the pilot attachment there's a tiny pouch on the bridle into which I can pull the knot in the bungy cord where it attaches to the bridle. This effectively lets out the pilot apex enough to make sure it is uncollapsed.

For me this gets rid of any delays on subterminal openings, and since I've made this a standard part of my packing routine, I feel I'm properly prepared should I ever pack/jump a rig with a kill line pc.

Ramon

Rainman

[ACMESkydiver 0]

Ok, just a quick follow-up question on this...say you do have a kill-line PC...and you have a packer pack your rig for ya...does anyone else always re-pack their own PC?

I always do because ya never know......not wanting a hard pull either. Too paranoid??

~Jaye
Do not believe that possibly you can escape the reward of your action.

[USPA 0]

No I don't. But I'm jumping pull-out, so i would be kinda hard.. . I do always check the bridle routing though, I even corrected teampackers at Deland for wrong routing. (different types, also the famous total)

The trouble with skydiving; If you stink at it and continue to jump, you'll die. If you're good at it and continue to jump, you'll see a lot of friends die...