Basejumper.com - archive

BASE Technical

Shortcut
Interesting base canopy design
Browsing the web this morning, I came across the xxlite paraglider from Ozone. It's a very odd ultralight design that doesn't have a bottom skin at all, but surprisingly enough it flies and flies well, apparently.

http://www.flyozone.com/...te/test-pilot-notes/

Of course my mind is curious and I wonder whether or not this design would be of use to the BASE world, and a bit more research brought this up:

http://video.mail.ru/...boyz/_myvideo/2.html

Apparently these things can fly with very little forward speed, which makes me wonder whether or not a deep enough brake setting would essentially make it a round parachute at opening, but it would fly just like a normal ram air once you pop the brakes.

The landing on the bridge jump video doesn't look all that smooth, I know, but the canopy seems smallish to me and I'm sure the aerodynamics could be improved on with a more intentional design (it looks to me like they just hacked off the bottom skin of some canopy they had laying around).

So does anyone know anything about the guys that jumped that pink canopy?

I'm pretty sure there is no significant market for how finicky such a canopy would probably end up being, but this sort of idle and hypothetical discussion is what the internet is all about.

And besides, imagine the aerodynamic improvement if you were to cut out half of your ultralight canopy's material, used 300lb dacron and stuck it in a modified camel-back Wink
Shortcut
Re: [shveddy] Interesting base canopy design
shveddy wrote:
(it looks to me like they just hacked off the bottom skin of some canopy they had laying around).

There was a period of time between round parachutes and ram air parachutes where single skin square canopies were not un-common in skydiving. I would almost bet that the pink canopy is probably surplus from that era.
Shortcut
Re: [Fledgling] Interesting base canopy design
The Russian jumpers at Kjerag in 97 or 98 had BASE specific canopies with that feature.
Take care,
space
Shortcut
Re: [shveddy] Interesting base canopy design
Like a Para-dactyl for BASE?

I've seen BASE jumps done on them. I have an ABA video with one, which I think might have been the first BASE jump in Australia.

I'm not sure there is much application in modern BASE, though.

Interesting, for sure.
Shortcut
Re: [shveddy] Interesting base canopy design
i wonder what a lineover or tension knot would look like on a no-ramair canopy like this one.... at least with ramair you have some cells inflated
Shortcut
Re: [TomAiello] Interesting base canopy design
Yea, kinda like the paradactyle, but Ozone got it to fly exactly like a modern ram air parachute. Check out this video:

http://youtu.be/gnN7JADnnLQ

What would happen if you took that same design concept, gave it a 2.5 aspect ratio, a steeper trim and a base lineset? (Oversimplification, I know)
Shortcut
Re: [base283] Interesting base canopy design
base283 wrote:
The Russian jumpers at Kjerag in 97 or 98 had BASE specific canopies with that feature.
Take care,
space

And they took them to terminal? Cool!

sky12345 wrote:
i wonder what a lineover or tension knot would look like on a no-ramair canopy like this one.... at least with ramair you have some cells inflated

Same thing that happens on a round parachute - a Mae West. It might even be more docile if the canopy is big enough to act as a drag device.
Shortcut
Re: [base283] Interesting base canopy design
base283 wrote:
The Russian jumpers at Kjerag in 97 or 98 had BASE specific canopies with that feature.
Take care,
space

Were they landing them OK?
Frank
Shortcut
Re: [Fledgling] Interesting base canopy design
Fledgling wrote:
I would almost bet that the pink canopy is probably surplus from that era.
Nope, it's home-made. the guy was actually brave enough to jump off of that low shit. Extremely stupid, but braveSmile
Shortcut
Re: [REDAKTOR] Interesting base canopy design
Do know of any intermediate steps he took before jumping off of the low bridge? Did he do it over water first, or was he just that confident in his sewing?
Shortcut
Re: [shveddy] Interesting base canopy design
No, no water, just that brifge. He broke himself up preatty good during one of those jumps btw
Shortcut
Re: [REDAKTOR] Interesting base canopy design
Discounting this design based on the fact single skins of the day did not outperform the current ram airs is not really fair. The first paraglider was also single skin btw. Pilot test notes seem to suggest alot of positives as a base canopy. Though i couldnt quiet understand the comment about landing. Does it have a poor flare? Bet the openings would be superfast.
Shortcut
Re: [imsparticus] Interesting base canopy design
In reply to:
Pilot test notes seem to suggest alot of positives as a base canopy.

- while it works.. many jumpers busted themselves but survived under partially inflated ram-airs due to malfuntions.... no chance with single skin - astalavista baby
Shortcut
Re: [sky12345] Interesting base canopy design
Very flawed assumtion imo. as this canopy demonstrates internal inflation does not create lift prevent/delay stall or keep the canopy inflated so to speak. Infact from the notes it seems bottom skin does the exact oposite. Probably because the inlet at the front restricts inflation at times and aoa's when the canopy needs all it can get.
single skin seems to cut out this step of the process it isnt at the mercy of internal inflation.
High performance applications probably favour the stability internal inflation provides but for base applications maybe not there just seems to be tomany positives to ignore.
Shortcut
Re: [imsparticus] Interesting base canopy design
i didnt mean object strike, stall and stuff.. i meant things like lineovers, broken lines, tension knots.. people landed on 3 inflated cells and survived.... with 1 skin, u essentially will be towing a flag in these situations - good luck :)
Shortcut
Re: [sky12345] Interesting base canopy design
Another flawed assumtion the single skin would have had just as much if not more inflated than the ram air.
Shortcut
Re: [imsparticus] Interesting base canopy design
imsparticus wrote:
Another flawed assumtion the single skin would have had just as much if not more inflated than the ram air.

No chance. Two skins are definitely better than one here.
Shortcut
Re: [Fledgling] Interesting base canopy design
I agree, When you watch a buddy's canopy getting ripped to shit by an object you quickly appreciate the over engineering that goes into a canopy.

I think that single skin would have been ripped apart to the point of free fall again.

I wonder how it does slider up or with a line over? since there is no pressure I assume the results would be a lot worse than a ram air canopy.
Shortcut
Re: [dan_inagap] Interesting base canopy design
I suppose this canopy could really change the game for low profile rigs, it's almost half the bulk without the bottom skin.

I'm interested to see what changes this design will lead to
Shortcut
Re:
Links for reference:
dropzone.com thread:
http://www.dropzone.com/...rum.cgi?post=4370819

PG discussion on the ozone wing and single skin canopies in general:
http://www.paraglidingforum.com/viewtopic.php?t=41947

Design notes, pictures etc of a kite:
http://2e5.com/kite/volkite/
Shortcut
Single Surface Canopy?
So single skin paragliders are becoming more popular...

http://niviuk.com/en/speed-wings/skin2
https://www.youtube.com/watch?v=ilx8Ch0eOR4

and they actually have pretty impressive performance characteristics

https://www.xcontest.org/...2018/09:39#fd=flight

Is anyone still looking at this application for base canopies? I imagine it would translate quite nicely to UL/wingsuit-specific gear.