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I know that the size of the canopy can make a difference in the altitude loss in a free fall jump, but I can't seem to find anything on static line jumps. The closest thing I could find was a thread where Vital Edge was asking for advice on jumping a 138' crane with a troll 285, worked for him. It seems to me that it would make at least some difference because of the longer lines and the fact that there is more material for the wind to unravel. Does anyone know if there is consistently an appreciable difference in altitude loss between smaller (200-240) and lalarger (290-330) sized canopies in sl and pca type jumps?

first lets not forget that this is THE INTERNET. What vitaledge SAID he did, he may not have done. Please don't use that as a valid data point until you have factual PROOF. It's foolish to believe something/someone you do not know.

secondly, BASE864 had a video awhile back, probably still on SD movies showing how he messed up his tailbone from 230ft span using 322unvented and then the difference doing vented. Many people have jumped it fine with smaller canopies - so I would say it does make a difference. shorter lines, less material..

good luck.

Yea I don't take everything I read on hear as fact, and I realize Vital Edge and many others can and probably have made some bogus claims. Was that an ff or sl/pca from the 230 span, have a link or a title i can search for the vid with? I know vents make a big difference, so lets say all canopies in this senario are vented.

IMO the person's weight is an equally significant factor.

I did a 2way with somebody else. I was 140lbs geared, jumping a zp blackjack 220 with a 48" PC taking a .5 sec delay. He was 230 or 240lbs geared jumping a Rock Dragon 293 or 303 and static lining. When we both had fully pressurized canopies, the center of his body was level with my canopy, so I was open 10-15' below him.

That's all the useful precise data I have.

Yes.

Also important is the model of canopy. I've seen some canopy designs that still maintain fairly consistent pressurization at the large sizes, but others that really suffer once you start looking at plus sized canopies.

Take a Blackjack 220 and a Dagger 313 from the same static line, and I'd guess you're going to see a very appreciable difference--perhaps 50 to 75 feet--in the altitude at which the canopy is landable. Make both canopies Daggers, and I'd bet the difference is quite a bit less. Make them both Blackjacks and I think it's even less than that.

well,as it comes to low alti jumps you cant just look at 1 thing whith out looking at others.

When you jump sl not only the canopy is the only point to look at..But you could make a list..
Is the canopy big or small?
vented unvented?
multi or not multi?
how long is your bridal?
By which force does your pin extract from your loops?
what kind of loops are you using?
did you pack whith a fully open nose?
How many wraps have you tightned your rubbernds on the gear?
is your velcro new or old?
How are your brakes set?
How do you exit?
how is you placed while falling?

when you have gont through all theese plus a few extra that you´ll find then you´l realice that even as canopy size does matter(bigger= slower opening)then its a matter of the complete system inkluding you...

when i last freefell 180ft i were 85kg(plus clothes and gear).
I used a 46 av zp pc
on a vented fox 265 no multi
standard bridal

But still manneged to have as long flight as the 2 others who did SL the same exit at the same time,whith same wingload..

A dead mate of mine did serval freefalls off 230-240ft w a unvented canopy in a velcro rig w a 42av zp pc.. whith no injuryes and fine flights(read 5+secs)
So i would say if you know how it works you can do many things,just dont forget that when you do push limits you will be in more danger

Personaly to a standard SL jump 140+ft i wouldnt be scared about 1 size btewn canopyes.. But as you mention it theres only big and small canopyes,perhaps your right tool is right between?

to this Q yes there is,a big difference,but why would a person get him/her self such a big difference canopyes?

Faber made some great points. he knows HIS gear and tries to manage many variables. by doing so, he gains consistency.

I bet with all his low altitude jumps, consistency and "appreciable difference in altitude loss" mean totally different things to the two of you. most newbies would be VERY hesitant to sl 180 ft, while Faber has freefallen it!

the best advice is to know your gear. (is it ragged out or brand new? how consistently do you pack?) learn on higher, more forgiving objects and then slowly work your way down. hopefully you will find your limits before you get hurt.

also another consideration is the density altitude what part of the country you jump, what time of the day, It make lot's of difference if you jump in 90 deg. heat compare to early morning and 65 deg. less density more altitude loss , if your going to make low jump you need all the advantage you can get

  

I'm not sure how any of the above have any input to opening times on a SL since they are all taken out of the equation on the way to line stretch/prior to break cord seperation.


Once again the primary stow would be taken out of the equation just before line stretch/prior to break cord seperation.

With the amount of force present by the time the tailgate is ready to blow open, I wonder how much of a difference two or three wraps is really going to make...unless you are using those black death black bands

I can't tell the diff between big and small but I can tell you this - if its helpful:
I weight 190pounds with gear and have consistently ff a 203ft B and A and consistently sl a 145 ft A.
Using a 280Blackjack with partial ZP top skin and 46 av zp PC. Had ample time under canopy on all jumps. I open my pinflap on the ff jumps though
The most useful factor for me is what I learned from Tom on my FJC - on low jumps go head high to minimise pendulum effect. also using Tom's packing method

i was jumping a 200ft B with a friend i pca'd him then i static lined he has a flik 290 with multi and i was jumping a rock dragon 266 no multi. from video the pca looked perfect. but compared to my jump i opend a little faster and had alot more canopy time. he has a higher wing loading than i do so i think it comes down to wing loading rather then canopy size. im an idiot though so theres my 2cents

In my opinion, the difference between canopy models (in your case Flik v. Rock Dragon) is more important than the size or wingloading.

If a Flik and a Rock Dragon open at the same altitude (or even roughly the same altitude) I'd expect the Flik to have more canopy time, simply because the Flik has a better glide ratio than the Rock Dragon.

This is exactly what happened to me and if you want I will send you the vid although it's dark and all you can here is voice, canopy opening etc.

The object was a S. 125ft. My gear was a Troll 265 with MDV. Deplyoment was PCA .5m from first (Bottom) pin to start of S folds. I exited and immedialtely had toggles out and buried. I landed just as the toggles went below my hips. All in all, from exit to standing on ground..... 4secs.

No other probs.....Hope this info helps you.

Just remember though....I could be lying through my teeth.....It is the internet afterall

Video here

Both jumps PCA'd in similar conditions, although I can't remember if the PCA itself was similar or not. Canopy is the same canopy - one jump was without vents the next year I had vents/covers installed and it made a huge difference at that low of an altitude.

I don't have the experience with different models of canopies at low altitudes like Tom does, but I do know that vents make a hell of a difference. And the bigger the canopy the more altitude it takes to open and get flying (i.e. producing lift).