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We are coming to learn that there are several bridges around the 90ft to 105ft mark here and they are typically over rivers. We are slowly developing the skills & confidence to tackle such projects and as such are interested in buying a round or at least a dedicated water rig. There exists quite a bit of information on water rigs alas most of it is dated and some is not at all clear. The community has been most helpful to us recently and once again I request advice as per:

1 – Does a round open as fast as a square?

2 – Does a wet round open as fast as a wet square?

3 – Apex still offers the H20. CR (Asylum) used to offer the Tektite but seem not to now. I saw something in a thread mentioning Nano (I think) from Morpheus but can find nothing on their site. Do you know of anyone offering Base specific rounds?

4 – I used to jump a Para Commander (when I first started sky diving) but that was almost in a previous life time and I really cannot remember its dimensions. I saw an old thread where someone mentioned that a 19ft round really isn’t sufficient to land on hard ground and almost the same applies to a 21ft round. So if any of you have experience could you please advise the appropriate size round for mainly landing in water but possibly also landing on hard stuff.

5 – Any other advice is appreciated

Thanks in advance

John

a PC is 24ft unless it's a Russian (27ft) or a Jump (28ft). None of those will work for you.

I have some BASE jumps on a 24ft Phantom and a 26ft Strong Lopo Lite. Based on my personal experience and on what I have been told by others neither one of these are suitable for 90-105 ft.

I am just *guessing*, but even a 19.5ft round isn't going to be a good idea for low altitude- rounds don't start slowing you down untill fully inflated. So while you may get complete linestretch, you will just be streaming a wide sausage of a canopy on your way to fractured back or worse.

hmmmmmmm....
maybe something like this? (on a smaller scale)


it is what i was referring to here
paraflite xt-11

I can give you some infos, as I am a paragliding instructor an I been working on design of paragdling reserve wich are round (95% of them)

They open extremely fast, We have video with emergency opening at 25 metres of the ground (80 feet) and the guy is allreay falling at 10 m/s under his paraglider
BUT there is big diference with classique parachute canopy.
Our are not made for hight speed opening (wich doesnt matter if you jump a 100 ft bride) and they have what we call an rope a the apex witch pull down the top center of the canopy (and make it larger)
This systeme is by the way called "pulldown apex"

So you get a canopy wich have a slower sink-rate than a round canopy of the same surface, because by pulling down the Apex, you have make the projected surface bigger.
Because the apex is down the the drag is good and the volume is about half the size of a classic round parachute (sorry if I repeat my points)

Now even this very efficient round parachute will need a quiet big surface to land you confortable (about 40 m2 for a 75 kg jumper.
But the volume and wheight of it is much samller as you have only one surface.
The packing is super simple and the opening really safe.
You can find on the net a lot of infos about them.
But I repeat don't use them at hightspeed, because they open so fast that they will break or break your bone.
By
Christophe

You should get hold of old Carl Boenish videos when they was training with small hand held rounds. Should get you and idea. I am so sorry to learn non of his work is on youtube or for sale anymore!
http://www.youtube.com/watch?v=gXCjmGI9Co0

Thanks to all and including Marty who PM'd me with some straight info.

What has become clear is that there are few benefits to jumping a round especially from low objects into water. They don't open or slow you down quicker than a square either wet or dry, they don’t land you softer, obviously can’t be steered as easily as a square and few manufacturers offer them. They do have the advantage of being packed quickly but for me that matters not.

This all surprised me as for years I saw rounds for sale on various BASE manufacturers sites advertised as “Water Rigs” and had mistakenly thought that they had distinct advantages for water jumps etc. So be it.

One last thing to mention - It is still more than possible to receive solid advice from this site which makes it very valuable to me and others in similar non mainstream locations.

Enough said

John

IIRC, the classic "water rig" utilized a cheap round, like an old skydiving reserve. some folks even used them to jump off a train, and then intentionally sunk their gear. they felt it better to avoid arrest.

it was all about expense, not technical merit.