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BASE Technical

juanitos
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Inflation- vented canopy
 I am asking for some info-please...Smile
If one is deploying at terminal speed a vented canopy - how much altitude is eating from the moment of pitching untill a full inflated canopy? Wing loading- 0.70
Jumping in tracking suit .
Dorkzonehero
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Post deleted by Dorkzonehero
 
jerry81
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Re: [Dorkzonehero] Inflation- vented canopy
What he said.

I'll just add that if you have time to unstow the brakes and flare before hitting the trees you could have probably gone a little lower still.
vid666
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Re: [Dorkzonehero] Inflation- vented canopy
dorzonehero, I am disappointed.

shortcuts have no business in BASE, and your question "What pilotchute are you using " actually has the following subcategories that need to be answered :

how many load tapes on the PC
are the tapes on the block or on the bias
what type of mesh
what type of handle
single or double centerline
juanitos
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Re: [vid666] Inflation- vented canopy
 Leaving jokes and irony apart, I am aware that the altitude one consume during deployment may vary according to equipment, packing, body position...
Nevertheless I need to have a clear opinion:what's the minimum and maximum of altitude loss?
15-50m??

P.S. that is a honest and reasonable issue any base jumper should know...
jakee
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Re: [juanitos] Inflation- vented canopy
In reply to:
Nevertheless I need to have a clear opinion:

Why do you need a clear answer? Are you about to hum it low on a terminal jump and then pull by the numbers?

I don't understand the logic behind your questions.
juanitos
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Re: [jakee] Inflation- vented canopy
It is logical to have a knowledge also about that.
Not because I'd like to have low pulls..TongueShockedShocked
wwarped
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Re: [juanitos] Inflation- vented canopy
juanitos wrote:
Nevertheless I need to have a clear opinion:what's the minimum and maximum of altitude loss?
15-50m??

P.S. that is a honest and reasonable issue any base jumper should know...

why?
honestly?
no one jumps with a device that can measure the distance accurately. sure, video and other tools can be used to help determine stuff, but why bother? what practical information does it provide?

a ton of factors (including pilot chute hesitations) can dramatically affect the distance required for full inflation. haven't you noticed that in skydiving? can you say, with confidence in your accuracy, how long your skydiving main will take to open?

most people prefer the experimental approach. i.e. just try it. reasonable jumpers will stack the deck in their favor, give them a bit extra margin, and then see what happens. this lets them build their judgment.

calculations are meaningless when the margin of error dominates the numbers...

do you really want to BASE jump, or are you attempting to do a class project?
GreenMachine
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Numbers
If you are doing a school project or just want to enjoy
some mental masturbation then do some research and
you should find the information you seek, it is out there.

If you are really, no bullshit, honestly I a skydiver and
newer BASE jumper then you should already understand:
that what someone knows on the ground or in the plane is
different than what they know at an exit point or in the air!

FYI - yesterday I deployed four times while staring at my
Suunto and every time the 'air consumed' was different Wink
cloudtramp
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Re: [vid666] Inflation- vented canopy
 
come on that's an easy one! Everyone know the answer: Why do you guys have to be so mean?
It's just common Knowledge that pulling at terminal with a tracking suit your opening's will "eat up" precisely 79.67365 feet. simple math really. I routinely begin my deployment at 80.79835 feet and this works great for me. It allows me just enough time to begin my flare and get my feet and knees together for the impact. Maybe to be in the safe side begin with deployments at 80.92367 feet until you get the hang of it.
dan_inagap
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Re: [cloudtramp] Inflation- vented canopy
Where's Sangi when you need him? These technical BASE questions aren't for us Tongue

Hi Juanitos, A lot in BASE is getting the feel for things, I think with jumps and experience comes the knowledge of what your rig can do and what its limits are. As you do different delays with different pack-jobs you will learn the opening characteristics of your rig, and how best to achieve the opening you are looking for. Correct me if i'm wrong please Smile
juanitos
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Re: [cloudtramp] Inflation- vented canopy
Finally I got some numbers...CoolWink
I can not figure out why it took such a long time to find out this precious secret..!!
TongueWinkLaugh

Thanks bro!Sly
yuri_base
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Re: [juanitos] Inflation- vented canopy
juanitos wrote:
It is logical to have a knowledge also about that.
Not because I'd like to have low pulls.. Tongue Shocked Shocked

How dare you to be logical, researching, thoughtful at Dorkzone #2? Angelic How dare you to ask BASE Gods a simple question? Shocked

Since I'm not a BASE God or Dorkzone Hero, I'll simply answer what I know from my experience, research, observation - and only about wingsuit: a typical wingsuit deployment with BASE canopy from pull (from full flight at glide ratio ~2.0 and more) to fully inflated canopy takes about 150ft (~50m). Vented vs. nonvented - imho, little difference on average because 1) larger part of altitude consumed by deployment is from pull to line stretch and body swing during the initial deceleration caused by first stages of bottom skin expansion, which depends little on vented/nonvented; and 2) non-vented canopies can open faster than vented sometimes, depending on packjob and oftentimes random factors beyond your control. Also, if a 180 happens before the canopy starts the inflation, more altitude is consumed (I'd say, it least 100' more) because of the surge towards the ground when you swing back.

Yeah, that's a lot of verbal vomit before you get some simple answer:



Dorkzonehero

PM Friend



Mar 26, 2010, 5:19 PM
Post #2 of 13 (418 views)
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Registered: Sep 4, 2007
Posts: 4

Re: [juanitos] Inflation- vented canopy [In reply to] Quote | Reply
Whoa whoa whoa...I would love to help you to get started on your first terminal jump here, but you gonna have to provide a lot more information that if you need this type of info.

- What type of canopy is this
- What is the state of the material. Could you provide test results from a porosity test of the material in question.
- What is the lenght of the lines
- How many times do you wrap your primary stow
- What are the dimensions and specs of the rubber band used in the packjob
- Do you tailgate, slidergate, directcontrol with one or multible rubber bands
- How many lbs of pin tension do you have?
- How do you fold your material
- How do you fold your nose
- What pilotchute are you using
- How do you fold the pilot chute
- How long is the bridle
- What kind of trackpants
- What is the vertical and horizontal components of the total speed
- How do you pitch the pilotchute
- What is the temprature
- What is the relative humidity
- What is the air density at the deployment altitude.
- Is the air density the same through the whole inflation sequence, or will you be going through any inversion layers.
- What is your definition of a fully inflated canopy

Its a common misconseption that deployments are actually eating altitude. I have measured the altitude of objects after many deployments, and they never change. To the altitude, its like the deployment never happened. Its like some kind of Bermuda triangle mystery.

dorkzonehero.net basejumping expert.




jerry81

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Mar 26, 2010, 6:22 PM
Post #3 of 13 (382 views)
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Registered: Nov 20, 2002
Posts: 51

Re: [Dorkzonehero] Inflation- vented canopy [In reply to] Quote | Reply
What he said.

I'll just add that if you have time to unstow the brakes and flare before hitting the trees you could have probably gone a little lower still.




vid666

PM Friend

United States


Mar 26, 2010, 7:21 PM
Post #4 of 13 (360 views)
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Registered: Jun 10, 2003
Posts: 839

Re: [Dorkzonehero] Inflation- vented canopy [In reply to] Quote | Reply
dorzonehero, I am disappointed.

shortcuts have no business in BASE, and your question "What pilotchute are you using " actually has the following subcategories that need to be answered :

how many load tapes on the PC
are the tapes on the block or on the bias
what type of mesh
what type of handle
single or double centerline




Dorkzonehero

PM Friend



Mar 26, 2010, 7:45 PM
Post #5 of 13 (347 views)
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Registered: Sep 4, 2007
Posts: 4

Re: [vid666] Inflation- vented canopy [In reply to] Quote | Reply
Yeah, I know Im sorry, this was just to get the conversation started, I realized after my post I completly forgot about

- What type of slider, sail, fine mesh,big mesh, big mess
- Aspect ratio of the slider
- Is the slider mounted upsdie down YES/NO
- Length of the risers
- Wear and tear on the closing loop
- Type of material on the container
- Description of body position while deploying
- Weight of shoes will make a huge difference, If they are heavy, the pendulum effect will be with greater weight and can temporarly change the angle of attack while inflating

Then there is of course the other factors. The canopy may be possesed by the devil. And it may have lots of bad juju. If you belive in that stuff, the extra weight of your worries changes the weight distribution completly. I had a horrible devil problem in my canopy once, had to send it to that wizard who basejumps. It didnt do shit except it came back with the blood of 13 virgins on it.

I think colors are important too. Dark colors in sun will heat material faster creating an area of lower pressure over the canopy which I think will speed up the canopy opening, but I am open to debate on that one.




juanitos

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Mar 28, 2010, 6:33 AM
Post #6 of 13 (125 views)
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Registered: Aug 29, 2009
Posts: 45

Re: [vid666] Inflation- vented canopy [In reply to] Quote | Reply
Leaving jokes and irony apart, I am aware that the altitude one consume during deployment may vary according to equipment, packing, body position...
Nevertheless I need to have a clear opinion:what's the minimum and maximum of altitude loss?
15-50m??

P.S. that is a honest and reasonable issue any base jumper should know...




jakee

PM Friend



Mar 28, 2010, 6:42 AM
Post #7 of 13 (118 views)
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Registered: Dec 5, 2003
Posts: 101

Re: [juanitos] Inflation- vented canopy [In reply to] Quote | Reply
In reply to:Nevertheless I need to have a clear opinion:

Why do you need a clear answer? Are you about to hum it low on a terminal jump and then pull by the numbers?

I don't understand the logic behind your questions.




juanitos

PM Friend




Mar 28, 2010, 6:44 AM
Post #8 of 13 (116 views)
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Registered: Aug 29, 2009
Posts: 45

Re: [jakee] Inflation- vented canopy [In reply to] Quote | Reply
It is logical to have a knowledge also about that.
Not because I'd like to have low pulls..




wwarped
Moderator
PM Friend

United States


Mar 28, 2010, 7:20 AM
Post #9 of 13 (109 views)
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Registered: Nov 9, 2004
Posts: 2135

Re: [juanitos] Inflation- vented canopy [In reply to] Quote | Reply
juanitos wrote:Nevertheless I need to have a clear opinion:what's the minimum and maximum of altitude loss?
15-50m??

P.S. that is a honest and reasonable issue any base jumper should know...

why?
honestly?
no one jumps with a device that can measure the distance accurately. sure, video and other tools can be used to help determine stuff, but why bother? what practical information does it provide?

a ton of factors (including pilot chute hesitations) can dramatically affect the distance required for full inflation. haven't you noticed that in skydiving? can you say, with confidence in your accuracy, how long your skydiving main will take to open?

most people prefer the experimental approach. i.e. just try it. reasonable jumpers will stack the deck in their favor, give them a bit extra margin, and then see what happens. this lets them build their judgment.

calculations are meaningless when the margin of error dominates the numbers...

do you really want to BASE jump, or are you attempting to do a class project?




GreenMachine

PM Friend

Florida, United States


Mar 28, 2010, 9:34 AM
Post #10 of 13 (91 views)
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Registered: Jan 24, 2003
Posts: 2359

Numbers [In reply to] Quote | Reply
If you are doing a school project or just want to enjoy
some mental masturbation then do some research and
you should find the information you seek, it is out there.

If you are really, no bullshit, honestly I a skydiver and
newer BASE jumper then you should already understand:
that what someone knows on the ground or in the plane is
different than what they know at an exit point or in the air!

FYI - yesterday I deployed four times while staring at my
Suunto and every time the 'air consumed' was different




cloudtramp

PM Friend

United States

Mar 28, 2010, 11:15 AM
Post #11 of 13 (57 views)
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Registered: Oct 25, 2004
Posts: 154

Re: [vid666] Inflation- vented canopy [In reply to] Quote | Reply

come on that's an easy one! Everyone know the answer: Why do you guys have to be so mean?
It's just common Knowledge that pulling at terminal with a tracking suit your opening's will "eat up" precisely 79.67365 feet. simple math really. I routinely begin my deployment at 80.79835 feet and this works great for me. It allows me just enough time to begin my flare and get my feet and knees together for the impact. Maybe to be in the safe side begin with deployments at 80.92367 feet until you get the hang of it.




dan_inagap

PM Friend

South Africa


Mar 28, 2010, 1:16 PM
Post #12 of 13 (32 views)
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Registered: Mar 17, 2009
Posts: 70

Re: [cloudtramp] Inflation- vented canopy [In reply to] Quote | Reply
Where's Sangi when you need him? These technical BASE questions aren't for us

Hi Juanitos, A lot in BASE is getting the feel for things, I think with jumps and experience comes the knowledge of what your rig can do and what its limits are. As you do different delays with different pack-jobs you will learn the opening characteristics of your rig, and how best to achieve the opening you are looking for. Correct me if i'm wrong please
cloudtramp
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Re: [yuri_base] Inflation- vented canopy
You still didn't answer his questions about tracking suit deployments Yuri.. Who cares about wingsuits! Is anyone even still using a parachute with those things??? that is SOOO last year! Join the Jeb Cordless school of BASE and you will never have to be bothered with doing another pesky packjob again... Which of course leaves plenty of time for smoking reefer, drinking yourself into an oblivion and let's not forget all the tranny hookers and blow that need to be abused and consumed as part of this daily BASE Life of ours. Sheesh! amatuers.
yuri_base
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Re: [cloudtramp] Inflation- vented canopy
Yeah, I didn't answer original question, I answered what I know. My main point, however, and the whole reason I entered this thread, is not to answer per se, but to serve as an example to experienced, thoughtful, polite jumpers who still value sharing their experience and information in various ways but who're hiding in their woodwork because they're outnumbered by dorkzone heroes. Don't be PusSiEs bIG, guys, come out of the shadows!

It is very showing that His Majesty Moderator Himself is one of the top dorkzone heroes. wwarped, what value do you bring to the world with a reply like this?

wwarped wrote:
why?
honestly?
no one jumps with a device that can measure the distance accurately. sure, video and other tools can be used to help determine stuff, but why bother? what practical information does it provide?

a ton of factors (including pilot chute hesitations) can dramatically affect the distance required for full inflation. haven't you noticed that in skydiving? can you say, with confidence in your accuracy, how long your skydiving main will take to open?

most people prefer the experimental approach. i.e. just try it. reasonable jumpers will stack the deck in their favor, give them a bit extra margin, and then see what happens. this lets them build their judgment.

calculations are meaningless when the margin of error dominates the numbers...

do you really want to BASE jump, or are you attempting to do a class project?
vid666
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Re: [yuri_base] Inflation- vented canopy
on behalf of all the dorkzoneheros I would like to apologize to you for being so unthoughtful.

I bring no value to this place other than peddling gear. I do keep myself well entertained through the never ending stream of moronic questions though, so I am happy.

However, since you bothered to ask - what value do YOU bring ???
yuri_base
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Re: [vid666] Inflation- vented canopy
vid666 wrote:
on behalf of all the dorkzoneheros I would like to apologize to you for being so unthoughtful.

I bring no value to this place other than peddling gear. I do keep myself well entertained through the never ending stream of moronic questions though, so I am happy.

However, since you bothered to ask - what value do YOU bring ???

You won't ever see that value, because you're blind. Wink

Besides, Paul, I told you to fuck off a couple of times personally, eye-to-eye, so following me maniacally like you do in the forums, are you waiting to hear another one? If yes, consider that you got it. Angelic
wwarped
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Re: [yuri_base] Inflation- vented canopy
yuri_base wrote:
It is very showing that His Majesty Moderator Himself is one of the top dorkzone heroes. wwarped, what value do you bring to the world with a reply like this?

once again, you fail to note a certain detail.
I do NOT moderate this forum. I am but a simple user here.

my response to the poster is to try to get them to realize they are asking the wrong questions. the actual answer, if known, is not particularly pertinent to most jumpers, in most situations. if you would prioritize the information required, this thread focuses on something waaaaaay down on the list.

as for YOU...
you continually insist on violating rules.
- you ignore my PM's, so you can not follow my requests as stated by The Rules
- you post in the wrong forum, another violation of The Rules
- you complain about the moderation, yet another violation of The Rules

I have refrained from penalizing you. I have let you be, even though you do not reciprocate. if you want a more courteous site, why not set an example. simply answer the question without complaining.

surely someone who grasps advanced mathematics can grasp these basic concepts. unfortunately, I see you trusting your IQ and skip the little things, like that I have no moderating authority in this forum. you don't first ask if a question is appropriate. you enjoy the complexities far more.
yuri_base
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Re: [wwarped] Inflation- vented canopy
In reply to:
once again, you fail to note a certain detail.
I do NOT moderate this forum. I am but a simple user here.

You're right. I failed to go to the forum listing and see that only aaron-basejumper, outrager, xmesox are moderators. (you're still greeny here, with "Moderator" label under your userpic).

That doesn't change my point at all. You ARE still one person. You still slice and dice threads like you just did in the General forum with my thread that was specifically posted there, not in Suggestions and Feedback. And it shows here, too. You talk here like a slicer and dicer. Re-read your reply to juanitos and think - "do I sound like an asshole?"

Do you know juanitos?

Why you're immediately making an assumption that juanitos knows nothing about BASE?

Why you're talking to him from high above like God?

"why bother?" - What kind of reply is that?! Why YOU bother?

"haven't you noticed that in skydiving? can you say, with confidence in your accuracy, how long your skydiving main will take to open?" - Why all this Negative Nancy tone? Again, do you know juanitos to talk like this?!

just try it. - Is this your approach to planning jumps?!

the margin of error dominates the numbers... - Huh? Are you saying that your BASE canopy might occasionally take 1000ft to inflate?!

do you really want to BASE jump, or are you attempting to do a class project? - Again, do you know juanitos to spill your sarcastic shit like this?!

- you ignore my PM's, so you can not follow my requests as stated by The Rules - Huh? Ignoring your PMs is a violation of rules? What kind of Nazi rules are that? Can you quote them here?

Yes, I replied to your last PM, "as I said, i'm deleting your pm's without reading. you can save your time by posting what you want to say openly in the forum, i don't have any secrets with you.

there's no reason to reply to this, either - it'll go to trash immediately.

thank you for your cooperation." - as I was tired of reading your senseless ramblings you chose to send privately for some reason. So what?!

you post in the wrong forum, another violation of The Rules - Huh? I was specifically posting in General forum to learn the opinion of regulars. I didn't want to make a suggestion to make changes to site's software before I knew that many people would like it. How's that a violation of Zee Rulez?!

- you complain about the moderation, yet another violation of The Rules - Really? What kind of Nazi site is this then?!

I have refrained from penalizing you. I have let you be, even though you do not reciprocate. - Thank you so much, your Majesty! You're so gracious! I'm guilty of so many crimes here... OMG. But since you're not a moderator in this forum, you can't ban me from here... can you? Laugh

surely someone who grasps advanced mathematics can grasp these basic concepts. unfortunately, I see you trusting your IQ and skip the little things, like that I have no moderating authority in this forum. you don't first ask if a question is appropriate. you enjoy the complexities far more. - Huh? I'm the only one so far in this thread who tried to answer the question directly. You really need to think hard, "why I have to first ask if a question is appropriate?" Do you always approach questions like this in real life? Pedestrian: "How to I get to Empire State Building?" Wwarped: "Why you're asking? You can do your research. Are you planning on jumping off it? If you do, you won't ask this question." Stranger: "Do you know where the nearest subway station is?" Wwarped: "Why you're asking? Do you want to blow it up? What's in your bag?" etc. etc.

Jeez, this is the most ridiculous thing I've ever dealt so far.

Why don't you ban me, Mr. God?
wwarped
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Re: [yuri_base] Inflation- vented canopy
again, you seem so offended, you miss a variety of points.

for example: I mentioned the margin of error. calculations may very well prove to be done well, but in free-fall most jumpers are limited to either their eyes, or an altimeter. I simply do not know how to measure accuracy of an individual's eyes. as far as barometric altimeters, in the US, the error allowed on a precision altimeter by the FAA is +/- 75 feet. thus pilots that can not see the ground rely on an instrument that the reading can vary by as much as 150 ft. I seriously doubt the standard altimeter used by a jumper is more accurate. trusting precise calculations permits detailed planning. true. I just fail to see how such plans can be implemented when the jumper can not know their position in real time. the knowledge of how long it takes for a parachute to open just is not actionable. (that is even before one considers the variability that pc hesitations introduce.)

please educate me where I am wrong. how can someone constructively use the answer to the OP's question? wouldn't that be a positive way to set an example?

[I'd rather focus on one topic rather than your laundry list of gripes. it is on topic and should afford you the opportunity to illustrate your views.]
yuri_base
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Re: [wwarped] Inflation- vented canopy
In reply to:
for example: I mentioned the margin of error. calculations may very well prove to be done well, but in free-fall most jumpers are limited to either their eyes, or an altimeter.

Huh? Who's talking about calculations? Only you. From moment you pitch to moment the canopy is fully open, it consumes some altitude. This altitude, while it obviously varies from jump to jump, from jumper to jumper, from canopy to canopy, from pack job to pack job, ad infinitum, still has some ballpark average. Most jumpers would agree that BASE openings are quite consistent and not like "error margin dominates the number itself" like you say. If the latter were the case, everyone would do static line from bigwalls "just in case the canopy will magically snivel for 5000ft".

So, depending on type of jump, the opening typically takes Xft. +/-, of course.

So you could have simply answered, "From my experience, Xft." Or not answered at all, if you do use altimeter on your BASE jumps. Laugh

In reply to:
in the US, the error allowed on a precision altimeter by the FAA is +/- 75 feet.

So, if terminal opening takes ~250ft, +/- 75 feet margin of error is greater than 250?! Can you just say, "250ft +/- 75 feet"? Do you really need to write your senseless long posts with nothing in them?

In reply to:
the knowledge of how long it takes for a parachute to open just is not actionable. (that is even before one considers the variability that pc hesitations introduce.)

What kind of parachute you jump in BASE, then, that you have so little faith in it?! Safire 2? Sit in the saddle and wait, maybe the slider will come down, maybe not?

Of course, sometimes shit happens, but the average, ballpark estimate of altitude consumed by BASE canopies is actually quite a reliable number, otherwise there won't be BASE at all.

In reply to:
please educate me where I am wrong. how can someone constructively use the answer to the OP's question?

I answered your question. I answered original poster's question to the best of my knowledge (wingsuits) to start the positive conversation where people ACTUALLY answer questions.

You still failed to answer it. Jeez, that must be tough to BASE jump and have no idea how much it takes for canopy to inflate.
juanitos
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Re: [wwarped] Inflation- vented canopy
I do know that in skydiving it takes some more distance for opening. I just wanted to know how much would be in base - a minimum and a maximum according to the many variables..naturally!
I don't think it was such a stupid issue...but some base Gods instead of answering started with ironies , mocking etc...
We are supposed to help others and share info on this forum..and not to fight each other...Life is short...and may be even shorter in our case ..Just remember that before being mean with others...
juanitos
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Re: [yuri_base] Inflation- vented canopy
Thanks Yuri for posting that info on wingsuit openingsSmileSmile
wwarped
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Re: [juanitos] Inflation- vented canopy
my point, which appears lost on at least one user, is that this information is NOT particularly useful. it may be interesting, but not a priority. it is an intellectual curiosity.

most BASE jumpers do NOT even wear an altimeter. dial altimeters would prove difficult to read accurately. most simply trust their eyes.

if you were a real jumper, you'd know this. if you are an aspiring jumper, you really need to focus on other information.

despite the length of this thread, you have failed to answer 2 questions. if you would answer them, you might receive friendlier answers.

1) what is your BASE jump experience? we can't give quality advice pertinent to your experience and understanding without knowing it.

2) why is this information so critical to you? even Yuri, who supports you, can't answer it. he loves data. if it were important to people, it would be readily available. (personally, I have never done anything to determine a number for my gear.) this seems uniquely important to you, so why?





ps
because you have failed to answer even 1 of the above questions, it looks like you don't show any respect for the community here. you seem to lack effective forum courtesy and politeness. yet you seem shocked that people respond in kind. do you not see a link between how you present yourself and the quality of response?
GreenMachine
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Hmm, Deduction
There are numerous different free charts online that
provide novice BASE jumpers with suggestions on how
to setup for jumps from different altitudes - including
slider position, PC size, PC placement, and of course
the deployment method.

There are also numerous free online sources of data on
amount of altitude traveled during freefalls of different
lengths of time.

So a BASE jumper should be able to use both of these
free and available data sets to back into an estimated
number that will likely be much more accurate than
their own estimation of time while in freefall.
robibird
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Re: [juanitos] Inflation- vented canopy
Slider Down case:

The altitude required as minimum would be between 120-160 FT, that is of course conservative calculation. ( you may go lower and be fine )
Canopy need to be properly packed
PC has to be in proper relation with the canopy size

Slider Up Terminal speed case :

If the canopy is in proper condition
If the canopy has proper brake settings for the weight of the user
If the PC is right size, slider right size..
If the weather condition is average
If the opening altitude is not extreme Vented or not vented canopy... all that play

The altitude need it is roughly 200 FT-250Ft
But only if all is close to perfect or perfect. Time from begining to ending of the opening proces is between 2-3 second.
By this frame I am saying that canopy will be opened and canopy will be useful and flyable. Not just opened.
Inflated canopy does not mean that jumper is safe as the kinetic energy is still there and canopy still falling w the jumper fast until it starts to fly.
That is why Brake setting is important.
Also smaller canopy would open faster but until it starts to be useful will eat more altitude.
Bigger canopies opens slower but starts to fly faster , meaning need less altitude.
Here we comes to important BASE rule; If the jumper is on the margin between two sizes, go for bigger canopy as it will be better for the jumper on the long run.

Cheers R
TreeRat
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Re: [juanitos] Inflation- vented canopy
how can you answer a question like this with out totally guessing no matter how much info you have on the canopy or jumper......at terminal speed your tossing a wad of nylon into a hurricane force wind.....it will never be the same .....
juanitos
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Re: [robibird] Inflation- vented canopy
Thanks for sharing this infoSmile
kiwibaser
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Re: [robibird] Inflation- vented canopy
Thanks Robert for giving an example of a good answer !!!
(your post is simple and informative as 95% of your posts are)

Some can criticize juanitos for not searching enough (or at all) to answer his question (or reconsider it's importance) ....

YES! 95% of the info you need is all-ready there, all you have to do is search ...

BUT! you'll spend LOTS of time to filter all that useless posts, off-topics and turtles love affairs..

not everyone have the same patience to go through that painful proses

So instead of making things worse, by adding a dozen zero-information posts every time you see a question you think is stupid or dangerousShocked ....
JUST IGNORE IT!

This way newbies will not spend half an hour reading a search result with important looking title and lots of answers but no info whatsoever Unsure