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Hi,

Disclaimer: I am asking this just out of curiosity.. I don't want to do this! I know this question has "stupid" written all over it, but I just have to ask it somewhere and where is a better place than here?

What would I need to jump 30-90 ft objects? Is it possible to build a (round) canopy that will decellerate you enough to land soft (PLF, no broken bones) on the ground from this height? Maybe a parachute that has a mechanism to open instantly (spring loaded fabric; extending metal arms; etc..)?

Is this possible or just a stupid idea?

As a little boy I dreamed of jumping from our house with an umbrella, I guess this is where the idea derived from..

Sorry for stealing your time..

Max

Don't wanna hijack your thread but lets say that 30 - 70 ft objects are only jumpable if you have two guys standing 20ft higher holding open your canopy so you have instant opening (well...It's already completely open)

Now then...would 80 - 90ft objects be possible with a tard? I have no idea but I'm curious because lately I've been looking at my church and I was wondering whether a tard would get you down relatively safely

Hi tenshi,

I am not talking about nowadays base canopys, because I highly doubt that it would possible with them. Even a tard or a direct bag deployment has it limitations.. I am talking about a canopy specially built for that purpose.

Max

I've seen video of an 88' direct bag done over beach sand.

Check out Rocket Jump on http://www.objectjump.de/ Its in german, but i know you will understand.
For the rest of you:
Its a system system that shoots out the canopy, the pictures are from a 30m Objekt.

I think i have posted this before.

Franco

Oh. Ok.

Maybe with a Co2 powered release. If you don't blow a hole in your canopy.


I understand more or less. To bad there aren't any pictures of the actual rocket. I suppose forward movement is not obligatory for this to work?

You are probably talking about this jump.

As I said before I want to know about alternative ways of decellerating for very low heights. IMHO a modern 7 cell base canopy is to complex to use it for a 30ft jump in your backyard.. Has nobody ever thought about that?

Max

The system used by Peter G (I think it was developed at least in part by BASE 283) had a rocket deployment and appeared sufficient to allow 30 foot jumps. There's video of it floating around somewhere, but I can't seem to find it right now. In the video I saw he does a motorcycle jump from a low bridge (maybe 50 feet?) and a snowboard jump from a low cliff (it looks like the canopy is pretty much inflated and flying as he leaves the exit, probably through a combination of the rocket deployment and the forward speed of the snowboard).



Why do you think a round would work better?

I think you look for this one: http://www.objectjump.com/videos/BASE-Exp.wmv
Thijs

The rocket system sheds new light to my question.. Seems to me someone put well thought into that. Never heard of it before. Looks nice, but I question the reliability of the rocket firing, but I am no expert in rocket-science..


This is why I put this in brackets. To my understanding a round is simpler in its design and therefore in its opening than a square canopy. But I might be completly wrong with this.. I guess its because I still have the picture of the umbrella jump in my mind

FrancoR, thanks for your reply! I learn new things everyday here..

Max

a rope and belayer....

"Fixed 2" tape shows a 63-foot BASE jump. Exit point was over land, but the landing in a knee-deep water.

Yup, that's the one.




Well you did say 30-90ft

Basically what you need is an idea, engineer, talented rigger, and very experienced BASEr. Things get really complicated at low airspeeds/altitudes. The main thing you can't get away from IMHO is the amount drag needed in a passive system. Or lift in an active system. The volume of air needed is roughly the same to achieve an acceptable sink rate. It is a lot.
I think for what you want you would need a jet pack (nonflammable is best) or personal airbag system. At the moment, I only have resources for the personal airbag system. But I might could line the other up if thats the way you wanted to go.
PM me is you are serious.
take care,
space

Weren't there some folks that clamped an opened round canopy to a ring above them and then jumped from very low altitudes?

yo Space. please PM me. Having trouble getting through to you. Will be able to log acceleration data from launch to derive distance fallen, speed, particularly during the pilot chute toss and subsequent canopy deployment. It will be tested within a couple weeks.
Chris

I believe those folks were called the United States Army.

yes, they have the publicly known 250 (not sure this is really low, perspective) jump towers built back in the day at Ft Benning. They are still used to this day.

Are those the ones with round parachutes already opened and clamped lightly to a ring? I find that hard to believe.

<---have been to jump school Jaap... it's not "lightly" clamped.

some history for those of you interested
Lieutenant Colonel William C. Lee, a staff officer for the Chief of Infantry, was intently interested in the test platoon. He recommended that the men be moved to the Safe Parachute Company at Hightstown, NJ for training on the parachute drop towers used during the New York World's Fair. Eighteen days after organization, the platoon was moved to New Jersey and trained for one week on the 250-foot free towers.

The training was particularly effective. When a drop from the tower was compared to a drop from an airplane, it was found that the added realism was otherwise impossible to duplicate. The drop also proved to the troopers that their parachutes would function safely. The Army was so impressed with the tower drops that two were purchased and erected at Fort Benning on what is now Eubanks Field. Later, two more were added. Three of the original four towers are still in use training paratroopers at Fort Benning. PLF training was often conducted by the volunteers jumping from PT platforms and from the back of moving 2 1/2 ton trucks to allow the trainees to experience the shock of landing.


a longer history attacted in a txt file
tom, if that photo is a violation... take her down

Woah, very cool Leroy. Thanks for the references. Good stuff.

I wonder how low you could take something like that.

I believe the arms go out 40ft ... but you would have to dive through the rings that the 34ft(?) parachute is attached to . Could be dicy, but you are 40ft away... hitting it would be "harder" to do. 1.5-2sec I would say is a healthy delay.... cough cough

BASE 75 did his first jump using a ring, a bicycle wheel, and a round parachute from a military surplus store, done when he was 16 years old from a sub-100 foot bridge.

Bro I have just the set up for u should send me a pm ik could hook u up with but ive only jumped from as low as 30 feet its called a rope if you want to use a canopy just tie the rope around your neck it will be alot less painful remember not everyone gets lucky