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211'

will there be any shadows?
what color is the Raven?


start higher and work your way down. experience is the best way to determine how your kit works.

(or just jump it and wish for the best.)

damn call 911

It'll work.

~Jake

On a static 175 B, I was open in 3 seconds and had between 6-7 seconds (2 jumps) of canopy time... so with static you are looking at open in probably under 60-80 feet.

Probably not far off, but there are a couple of things to bear in mind:

First, open and flying are two completely different things. My experience with a vented Fox 245, exit weight about 170 lb, is that the canopy is open 70-80 feet down, but not flying until about 120. In the time between, it's building forward speed, but still acting more like an aerodynamic decelerator, and less like a wing.

Second, let's suppose it takes 120 feet for the canopy to start flying (possibly true for a vented Fox 245, but probably optimistic for a Raven III). Let's further suppose that TreeRat's lowest s/l jump so far is 300 feet. It's tempting to look at this one of two ways, both of which are misleading:

1. You've still got 70% of the altitude
2. You've only dropped 90 feet out of 300.

The problem with either of these is that your basement is 120 feet, not 0 feet. So, you've actually dropped 50% of your working altitude, not 30%. You'll have about half as much canopy time, half as much time to respond to problems. etc.

The basement altitude has a surprising effect on the numbers. Let's say a Raven III takes more like 160 feet to start flying (ballpark figure based on experience with an unvented Mojo). Then going from 300 feet to 210 feet, TreeRat would actually be looking at almost a third of the canopy time.

The bottom line, as wwarped said, is to take it slow enough that you can get an intuitive sense of what this curve looks like. Canopy, wing loading, elevation, and winds can all have a marked effect on these numbers, so you'll want to get an idea how they change, too. That takes a little while.

Michael

I've done probably a dozen static lines from 190ft with a raven3. static lines open pretty quick and I've gotten to land almost 200 ft away from the object. Probably flying around the 90 foot mark.

Its no problem with your setup but just remember that your not going to be flying far after opening.

You weigh much less. Factor that in as well.

That type of canopy were you jumping?

i'm 170#. i've done a few s.ls from 190 on a raven3.... opened, turned 180 and landed at the base. get a base canopy, please. mine started collapsing and scaring the hell out me. good times

A Troll 265 DW

best answer so far.

Really? My BJ260w/ZP has been open with full pressure at 30-50ft on the 5 s/l I have on it, and full control by about 70 feet. All static lines have been in calm winds. I have video of 3 of them.

I'm at line stretch about 20 feet down, break cord pops, canopy inflates practically instantly about 10-30ft and its fully open with no material movement, it then moves forward about 5 ft and down about 10-20ft and I have full control.

Near same results with my bj280

~Jake

Where are you getting your figures from? Are these measured, or estimated? That the canopy is fully inflated doesn't mean it's flying yet -- it just means that it's ready to fly once it picks up some forward speed. I watched one of crwper's low jumps, and would also say that the canopy had perhaps started to fly at 110 feet. If your canopy is fully flying by 70 feet, I'd be surprised. Are you saying that jumping from a 70-foot object, you'd expect to be able to flare out your landing?

+1

The B got jumped......but not by me........I don't believe my Raven would have made it over the street light .....the two vented that was jumped only cleared them by 20'.....believe this B was meant for me to watch and drive....but now I'm still left needing a B to get my base#

Seriously dude ? GET YOURSELF A REAL BASE CANOPY.
Being cheap in this sport will brake you.

brake? is that a pun?

it's whatever you want it to be LeRoy.

brake vs break

You brake to slow down; if your brakes fail and you drive through a plate-glass window, you will break it.

Like I said, whichever one you would like for it to be. I am not picky, especially when it comes to the great LeRoy.

Dude was just commenting that you made a pun, not saying I was perfect, just that you were a tad funny. Relax dude

Figures estimated from the experiences themselves and review of the video after the fact. Uploading video to youtube right now so you can see it. I'm on a slow ass haji net over here so it's gonna take a while, I'll post the link tomorrow if I get a chance. And as far as the 70ft flare out. If everything went exactly as it has on the 5 s/l's I'm talking about, I think I could flare out and have a nice soft landing on any surface from 80ft. I wouldn't even try that though

It finished quicker than I thought, here it is.
http://www.youtube.com/watch?v=OqTK3XdpfSM

regardless of how I spelled, my point was clear, on topic and more or less helpful.

your last two were pointless in the scope of the conversation.

have a good day, mr. "I need to respond to every thread"

That is an impressively fast opening. I suspect that the video is a little deceptive, for the same reason that wingsuit jumpers often look like they're flying up against a cliff, but to make that happen you do need some forward speed.

Crwper's working on some quantitative results that may help here, too...

dood, you didn't stand up that landing with a 18 sec canopy ride

I know. Pretty pathetic. I knew either way I wasn't going to get hurt, so I had to choose downhill nice easy landing, or uphill with the camera man...hehe. I chose cameraman.

That cliff is 195 to the water, and where I landed is 10-15 above water, probably closer to 10. I think my estimates are give or take 5 feet.

Looking at the video you uploaded.

The canopy appears to be fully open about 2-3 line lengths down. Add the length of the lines themselves, and assuming 20 foot lines, and your feet are about 60 feet down at bottom skin inflation (about 0:03 in the video).

The canopy appears to be flying about 0:04 in the video, after a slight rock as it picks up forward speed. At that point, it appears to be about 4 line lengths down the cliff, which puts your toes about 100 feet down.

Shortly after that you clear the toggles (good job, by the way).

It's hard to judge the distances on that particular video, because it's shot from an angle looking up. This means the canopy could be flying straight toward the camera, and all you'd see is a little change in size. A better angle would be from the side, approximately at the altitude you expect the canopy to open.

The Black Jack is definitely a faster opening canopy than my old Fox, but I'd guess you're still taking at least 60 feet to open, and about 100 to full flight.

Michael

I'm not positive, but pretty sure the D lines are 18ft, 2-3 is 36-54ft, and then you said 4 line lengths 100ft, did you mean 5 line lengths or 80ft? 4 line lengths 72, 5 is 90.

mean average of line length is probably closer to 17'

Thanks for the evaluation

Four line lengths down to the canopy, plus the lines on the canopy to get you to the jumper, so 5 line lengths roughly to your toes.

I rounded to 20-foot lines for the same reason I didn't include a 6-foot body between the rig and your toes--there's no way the estimates are that accurate, so it's a bit misleading to include too many significant figures. For back-of-the-envelope type stuff, I consider the lines to be about 20 feet long.

Michael

I'm 5'11" but you can't count my head