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Can people give me there opinions on how they think pilot chute size relates to heading performance? The reason I ask is because I recently did a 15-1600ish jump with a 36"zp pilot chute and had a 180 with a face full of tower coming at me.

Anytime I've done the same jump with a 42" or a 38" I've had perfect on heading openings. I'm wondering if the smaller pc lifted the packjob out of the tray slower and allowed it to be affected by winds more. My pack job is pretty solid so I think that variable has been made as small as it can be.

Just for reference I'm jumping a 220 loaded at .75-.8ish.

it doesn't matter at all which alti you jumped from - it's your airspeed - thus your delay that makes the difference.

36" for a 220 canopy at terminal (9sec+) is just fine. It's also fine even if you are a good tracker or using a WS. Many people have used a 32" and are still here to confirm that.

a large PC crates more drag, and thus in theory is more likely to destroy your packjob on the way to linestrech.

This is the way I understand deployment happens :

PC is thrown
PC has enough drag to achieve bridle stretch
It pops pins/pulls velcro
as you fall away from your PC, the packjob is extracted.

the larger the PC - the higher the drag, thus the bigger difference between your airspeed and PC airspeed - resulting in faster linestretch, and subsequently a more chaotic opening.

a 38/42 obviously work fine as far as getting you open, but they stress the bridle attachment point more, and are going to give you harder openings. I have done all sizes from 32-42 to terminal and I believe the 42" felt harder. Also while goign terminal, you would hate to have a premmie - and having a smaller PC allows for it to be tucked away more in the BOC, not to mention most smaller 38 and smaller PCs mostly made with external PVC handle, as opposed to majority of 42s only made with no handle or a cordura disk, which sticks out way too much for my liking at high airspeed jumps.

Good morning to you too.

What about a 32"PC at terminal jumps? The same 220 canopy but vented and tracking suit- nice openings?

if you want to know how things react at terminal, think skydiving!

what size pc do you use there?
has it ever hesitated, or seemed "weak?"
have you considered swapping out a BASE pc for your normal skydiving one?

if you want to be comfortable with your decisions, would you prefer deciding on your own experiences, or an anonymous poster?

(heck, don't listen to me! )

 

I can not skydive with my Base canopy ..is too large for my skydiving rig!
My skydiving canopy is 150 feet...so it is no use to compare how reacts the same PC for the 2 canopies...
I hope somebody knows from his own experience how works this atair sail slider in Base...

I have tracking gear...so I'' track far from the wall..

I would feel very uncomfortable with a sal slider on a BASE canopy. It's job is to catch air which, in turn will lengthen the snivel which will then allow more time for the possibility of an off heading/ line twist.

I will always use a mesh slider in the BASEment.
A. I like to pull a little low and,
B. if you ARE in a pinch and need that fucker to open NOW and on heading, a sail slider ain't gonna help.

My .02

Thanks for your kind advice..
Then, I'll switch to my small mesh slider..

so?
I thought you were concerned about the effectiveness of pc's... no need to switch canopies, just pc's! see how the different sizes affect the speed of deployment.

you can also look at the size of pc used on the giant student rigs. (you don't think your dzo would like hesi's on student gear, do you?)

it's not that complicated, unless you don't trust your judgement!

My track and delay are manly enough thank you. If I wanted to start a dick measuring contest that's what I would have named the thread.

As far as 180s go, I don't care for them regardless of altitude. I prefer on heading openings but thats just me.

As far as being stable at pc pitch your right... my strategy is to get as unstable as possible and pitch in a hard spin. That seems to work best.

Thanks all for the input.
@ Vid666- thanks that makes sense about the larger pc's desturbing the packjobs more at higher airspeeds

Yeah good point! I guess I knew it would be a faster extraction but, I didn't think about what affect it would have on you pack job. . .

on every single jump, the jumper need to care a lot and observe the heading of the canopy. Why?! Self-confidence!

next step of such thinking would be: '' hey, it is high, it is skydive!''
Well, wonder why 80% of the fatalities happens on slider up jumps... maybe this is the answer?!

haha, well seems to me... when you ask for opinions... you WILL get them.

and i tend to agree with Tree.

not so much dick measuring, but experience....

And sometimes 180s' just happen. Part of the chaos that is base jumping. I see you have 30 jumps and 10 objects on your profile. That is more than most of the population at large. Just last night I had to take a 7 sec. delay from a terminal object so I would be able to make the landing area. I had a 32" zp small mesh av pilotchute, and 15 deg. right opening. Nuf' said?

i do agree with that statement... but in that same line of reasoning... if you don't have the confidence of on heading openings (as in the case of the OP of this thread) then maybe you'll have the insight to not jump the exit point where it will matter, at least until you sort out your problems. it's all part of progression.

I'm confident with my heading performance Elliot, just trying to get some knowlege on why those random off headings happen everyonce in a while. I don't buy the randomness factor that most people seem to talk about when they can't find a reason why something happens. And I do enjoy and respect the opinions of people more experienced than myself, but the idea that something technically based can be influenced by how masculine or femminine you fall through the sky seems like more of a quip than an opinion.

yeah, man... but this is the internet.

and in this game, shit does happen. how is it that my friends can do everything right and anal and end up bouncing off a wall and dying, all the while i jump the same exact place with my 10min shitty packjob and don't get more than a 45? i just don't know.

hundreds of jumps later... i'm not all that confident in my heading performance, but i am however, confident in my ability to deal with what is dealt.

and that is why i continue to play the game.

I think you are misunderstanding the whole "randomness factor". It referrs to the myriad of things that can cause the deviation from the perfect heading. And at many times it's nearly impossible to put your finger on which one was the cause.

just a few things that can cause offheadings :

stiff riser covers - one release before the other = one side inflates before the other = offheading and/or linetwists

asymmetrical at pull time = you will start rotating if at terminal = linetwists

asymmetrical at pull time = uneven risers at linestrech = linetwists and/or offheading

sloppy packjob = chaos at opening = who the hell knows what may happen

lines getting out of trim = asymmetrical inflation = offheading

short slider up delay = chaotic snively opening = people calling you a pussy

freefall airspeed lower than natural wind = packjob gets oriented by the wind = discussed just a day ago

tailpocket velcro biting into some lines = uneven linestretch = uneven inflation = ....

your nice and tidy packjob, which you took extra 10 mins to make sure fills out the corners of the container nice, because as you know looks are everything, especially in nightBASE = packjob catching corners of the packtray due to aggressive tracking or exiting headup like Greenmachine does = packjob destroyed before reaching linestrech

I can keep going, but you get my drift...

thanks Paul... that was a nice list! haha.

[ I don't buy the randomness factor that most people seem to talk about when they can't find a reason why something happens. ]

Come on, you throw a "ball of nylon" off your back at 100 mph and expect it to do the same thing, everytime?

@ Blitzkrieg... good point
@ Vid666 that is a good list....lol... especially the part about the head up exit.

especially the part about the head up exit

Out of my 176 BASE jumps there are
some where I do actually exit well.

And for low, go & throw jumps going
off head high works just fine for me.

Maybe I need to post some videos
that don't show me screwing up

but where's the fun in that?!

Don't forget, probably the most common causes of offheadings is PC oscillation. Check your PC to be sure that it is attached symmetrically and that it was manufactured properly.
Using a PC that's too big for the job will also cause center cell stripping. There seems to be some disagreement over what role this plays in heading performance, but it's a factor to consider. If you're taking a healthy delay from 1500' you should be using a 36'' or 32'', especially with a 220 (lightweight) canopy.

Well it might have or have not any role in heading performance, but it seems to me that center cell stripping may have more to do with the possibility of the primary stow getting undone prematurely with any consequence that might follow ....
premature slider descent (?)
line over (?)
tension knot (?)

(but hey wtf do I know.... with no slider up jumps yet )

either way an over-sized PC is not a very good idea
(unless you have multi? )

Greg

Eh, personally I'm still undecided about the whole pc ocillation thing. Seems to me pilot chutes to wacky shit when you throw them out regardless. I figure the most important thing is that you have one in the first place.

here we go again with the center cell strip thing...
if you pre strip the center cell properly how should a strong pulling pc do to much bad stuff? a high speed deployment is so chaotic in itself i highly doubt a pc can do that much harm.
i'm a firm believer in big pcs, i prefer a 46 for slider down stuff(yes, also stowed) and rarely use a pc smaller than 38". i own a 36 f111 but mostly don't bother to put it in.

tell me, in the attached pic is this center cell strip or what?
if so whats so bad about it? its a pull from full flight with a 38" vented zp.

i never got the whole center cell strip thing anyways...

So, "Undecided, Pilot Chutes do wacky shit". Still don't buy the randomness part of deployment, or do you mean something else?

So, a 32 "PC should be working well for more than 11 sec , tracking suit and 220 canopy..? I am asking because some people advice a bit larger PC if using tracking gear..

Just about every gear manufacturer and FJC instructor
has published a chart with their opinions regarding the
recommended configuration, delay, PC, placement, etc.

So start with the one that matches your gear or your
training then modify as necessary. For example, if
the opening is brutally hard and makes you shit your
pants then maybe go with a smaller PC. OR if you
open way too low then pull higher or use bigger PC.

I have never done a BASE jump that lasted 11 seconds
but I have deployed a 220 after 11 seconds of tracking
and I am still alive to write persnickety posts

since you apparently did NOT do the homework I suggested, I guess I'll do it for you...


one vendor of skydiving pc's sells 24" pcs for 150 sq ft canopies and less.
the same vendor advises a 28" pc for greater than 150 sq ft.
2 different BASE manufacturers list the smallest stock pc at 32"

thus the BASE pc's are already 36% bigger than skydiving pcs that appear to work fine. obviously, BASE jumpers like larger pc's to prevent hesitations at real low altitudes.

this becomes more critical when many wingsuit jumpers report deploying lower than expected because of the visuals differ and the burbles created by their wings.

BUT...
that is not what you asked. you are only discussing tracking pants!

as far as I can tell, you have 4 options...

1) test out various pc's on your skydiving rig and see how they work for you.

2) just take a stab at it and go jump a big wall. just pull higher than the basement. I doubt you'll have a significant hesitation, but what do I know? if it gives you a warm & fuzzy, go for it. (obviously, jump off a wall that does NOT require a wingsuit or tracking pants to ensure an appropriate safety margin.)

3) continue listening to anonymous voices on the internet and stress over which one is most accurate for you. none of us really know your personal preferences, know your plans, know your gear, etc. how can any of us provide you accurate, customized advice?

4) quit BASE and increase your gear knowledge. educate yourself. return to the sport when you have purged much of your gear fear. do your own homework.

at this point, I'd suggest 4.
but as always, what do I know?
many say I don't even jump...





edited to ad:
ps
you could also go to that big wall with multiple pc's and watch a load or two. see what different people use, and how it works for them, before choosing for yourself.

if you are stressing over what size pc to buy for your first rig, ask your mentor/instructor!.

Since you are obviulsy too much of a pussy to find out the practical way, I will tell you.

Yes, a 32" works fine. I have used it for terminal and near terminal with canopies up to 300 sq ft (personal experience). I know of people to use a 32" for 6-7 sec delays as well.

YMMV

If your PC is assymmetrically attached or out of round, then this is an issue. What about all of those off-headings that are not due to improperly assembled gear?

Body position is where you are going to find it-- more than packing, or winds, or anything else (but at the same time I'm still recognizing that these are other factors in heading performance).

Whether it is slider-up or down, your stability and shoulder position during deployment, extraction, and inflation is going to have more of an effect on heading than anything up to that point. Spending hours on your packjob, waiting for absolutely perfect winds, etc, etc, doesn't mean anything if you can't control your body in freefall.

Your shoulders should be flat and parallel to the ground and as the canopy comes off your back, you should be able feel an equal pressure on both risers. If one shoulder is low or high, it is going to create unequal pressure on that riser before the canopy has even had a chance to open.

what's there to be undecided about ?

The PC is a half-sphere - it goes through the air creating pressure under the surface - that pressure (air) has to escape. If the PC built asymmetrically (which all are, perfect symmetry is just impossible) - the air is going to escape out the one side (edge) of the skirt, making the PC oscillate. However, as it's not freefalling, but rather being dragged past it's natural descent speed by the weight attached to it, the air starts spilling faster out the one side, thus forcing the pc to orbit around the bridle attachment point. Look at the BD video - lots of examples of that. Venting the PC at the apex will help somewhat, but is not a bulletproof solution.

I agree - having the PC, even a badly made one, that oscilates wildly, is better than not having one at all, and better than having a kick ass latest and greatest one that has a rubberband on it.

 Thanks a lot for all kind suggestions...
As concerning fear...I'll be back to Base in a while..Now I am still recovering and doing homework

P.S. nothing compares to tasting" the sweet kiss of the death"...no way to quit Base!!

You are asking for advice. Think of the quips as a rainbow, Only an enhancement to the rain if you choose the color you like.

Goodluck, I dream about Danish.......


I disagree due to my experience in BASEing. Bigger is always better in an indecisive PC decision.
Bill Booth has a thread on dorkzone stating that between 30 & 50 fps separation is best. He may be the expert on this.
Centercell strip causing a less than optimal opening is a myth IMHO, You can use your search button to figure out this mystery also.

My tip to you would be to not get your panties in a wad when people are giving you answers on the very topic you posted and use the search function.
Take care, wish you a great outcome.
space

Hey don't forget one or two things to the the Big pilot-chute debate. Is the drag factor under canopy. & it really only applies more to the lighter weight people under the smaller Sq.Ft. . Big PC's will give a different stall to the flair & you landing technique you normaly have & also give a distortion of Canopy in it's Trim while @ the same time, it is giving greater drag as a sky-anchor when you are pulling it behind you While it slows your air-speed and changes your normal distance in glide-path you are accustomed too .
.

hurumph hurumph, good shit, elliot