Release system on sit tube

[kansasskydiver 0]

I've looked at all the forums for freefly tubes and still have a question. I've got a "beginner" sit tube being sent to me this week. I'm not sure on the legnth or the width yet, but I think he said it was only like 8 inches wide and maybe 12 ft long? (may vary)

He suggested though that I have a rigger put a cut away system on it...

I'm not sure how a cut away system would work on a sit tube if it were to wrap up on yoru arm, but if all else fails don't you just let go?

But anyways, he said that I shouldn't jump it until I have a release system put on.

Anyone have any advice or pictures for a Sit tube release system?

Thanks in advance,

Chris "Flash" Armstrong

<--- See look, pink dolphins DO exist!

[Trent 0]

Hmmm... I think the best release system for a "sit tube" is your hand. Usually you just sit while holding the handle on the tube. If anything gets squirrely, let it go. Simple. If you're putting it on your feet, you'll need a releas system. They're routed like skysurf releases; down the leg and to a little release mechanism (i've seen 2 rings on tubes).

Be careful dumping with that thing... they scare me.

Oh, hello again!

[kansasskydiver 0]

Yeah that's what I thought too, just release it with your hand and that's your cut away system. I'm jumping a sabre 170 winged at about 1.5/1 hopefuly the opening will be just fine. i'm going to practice getting it out to my side first then i'll sit with it .

Chris

<--- See look, pink dolphins DO exist!

[JayhawkJumper 0]

Are you getting this tube from Joe? He probably thinks your going to attach it to your foot. A sit tube just has a bar of some kind that you hold onto and when you don't want it anymore, you just let go. The foot tubes I've seen have three rings on them with a cutaway similar to those on skyboards. One of the guys in Wichita has made a bunch of head-down tubes with three rings on them, so you could talk to him about that, but if its a hand tube, just hold on and let go.

[kansasskydiver 0]

yeah i'm getting it from joe, how did you know. see i thought it sounded kinda odd too, but he said that he didnt want to see me jump it until i put a cutaway system on it. i was pretty sure he understood it was for sitting, but he could have confused me with some one else.

<--- See look, pink dolphins DO exist!

[kansasskydiver 0]

I got the tube yesterday and got it all set up. I didn't put a cutaway system on it, but it's built that I can put one on in the event I hook it to my foot. The handle pivots and will allow the tube to rotate if needed, and it has a mesh guard on it to block a pilot chute going up. i tested it out on the highway at about 80 and it worked pretty well. not too much drag on the arm, but of course i know at 140 it will be different.

<--- See look, pink dolphins DO exist!

[Yoshi 0]

I love my tube, but make sure you get some instruction from someone who has jumped one before going out there for yourself...there are a few do's and dont's that you will want to know before jumping it... Im too lazy right now to write everything, but I am sure you can find it in a search..
-yoshi

_________________________________________
this space for rent.

[michaelflying 0]

question how many free fly jumps do you need before you can use a sit tube.

www.skydivekzn.co.za

[kansasskydiver 0]

Well I'm no expert of it, I'm going to be making my first jump on one this weekend, but looking at the aspects involved I would say atleast your D license and a majority of those being freefly jumps. Again jump numbers don't mean anything, but I think with the requirements of the D, if you have to land in a tighter spot becuase you chased it down, or having more people in the air with you while you are just the tubes bitch, having the air time is a key. I have about 335 jumps, of witch 275 are probably freefly jumps. I have jumps toys before, but didn't start till I have well over 200 and even then it scared the poopie out of me.

To put it best, I wouldn't suggest jumping a tube until you are stable in a sit, sideways, on your back, upside down, in a spike etc. The tube will have a mind of it's own and you won't really be able to use your one arm. I don't know, I say be a good freeflier and be able to stay pretty stable given the lack of use of your hands.

The other thing to watch for is the opening. I'll be jumping it on a sabre 170, stable, docile canopy that won't (or shouldn't) cause any spin while the tube is in the lines.

I guess though the main thing to remember is, if shit goes bad, let go, it's not worth trying to hang onto. And may I sugesst a pivoting handle so it doesn't spin up on you

Blue ones, sorry about the lack of advice. It's best to get with people who know your flying skills and ask them, I don't want to give the wrong impression

chris

<--- See look, pink dolphins DO exist!

[kansasskydiver 0]

Here are the pictures of the tube, handle sytem (pivoting) and anti pilot chute screening .

if you have any questions feel free to PM me. the handle cost me 7 bucks at the hardware store, the mesh 99 cents at walmart and to get it it all put together I took it to a shoe repair shop and they attached the X and put the eyelet thru the middle. total cost for the new attachment system was 19 dollars.

[PhreeZone 20]

What is the X made out of? Unless its webbing I'd be leary of attaching a handle there.

If Kris would ever give me my tube back or actually jump it I'd take pictures and show mine... I attaced a half loop handle to the hoop its self. On the WFFC DVD you can kinda see it as they go down the out side of the tube.

Yesterday is history
And tomorrow is a mystery

Parachutemanuals.com

[kansasskydiver 0]

the X is made of out doubled over webbing. 500lbs per piece, box stiched in the middle with a 1/2 inch gramet going thru it. it's more sturdy than it was in the first place. i'm no rigger so i can' tell you what type of fabric it was, but it's the same stuff as what the static lines are made from, only it's an inch wide.

chris

<--- See look, pink dolphins DO exist!

[kansasskydiver 0]

I jumped the tube yesterday, it was awesome! Not a problem at all. easy to hang on to, easy to deploy with and all. I'm glad I put the pivoting handle on it though because the tube did have a slow spin to it all I accelerated. It sure as hell slowed me down enough. i was sitting with the belly fliers. Now that I've done it once I'm open for questions about it or how to build the tube seeing as it worked

chris

<--- See look, pink dolphins DO exist!

[PhreeZone 20]

How long is your tube and whats its diameter?

Yesterday is history
And tomorrow is a mystery

Parachutemanuals.com

[michaelflying 0]

www.skydivekzn.co.za

[kansasskydiver 0]

It is 13inches in diameter and about 12 feet long. Just a beginner tube as I'm just a beginner to it I'll put a couple more jumps on it and then make a 20 footer. The only thing I'd change is making the end a little smaller than the opening because it's wasn't as sturdy as I would have liked it. The end flopped around and didn't fully inflate. I'll get the video on here sometime this week.

Blue 's

Chris

[VectorBoy 0]

Now that I've done it once I'm open for questions about it or how to build the tube seeing as it worked

chris

[PhreeZone 20]

Instead of using ZP which is hard to pick up at my local fabric store I used 1.1 oz nlyon on mine. Cost was $6.75 a yard in 60 inch widths. There was only really usable 58 inches but thats still a lot of material. My 18 foot 2 color tube cost about $45 for the material and about $25 for the hardware. $70 is alot better then the 200+ I was quoted for a ZP tube from a gear dealer. In terms of time... probally 7-8 hours and that included cutting, pinning, sewing, assembly and general screwing around learning the machine.

I did have to buy a sewing machine to do it, but its been used for lots of other thngs since then so it's paid off.

Yesterday is history
And tomorrow is a mystery

Parachutemanuals.com

[freakydiver 0]

NO VIDEO of the highway test?????????????????

-- (N.DG) "If all else fails – at least try and look under control." --

[kansasskydiver 0]

nope sorry, no video of the highway test. I have pics of the jump, but they are too large to upload. you can see the pics below. I made another jump on it last night and it didn't go as smooth as the first one. Had a spin to it and wasn't inflated all the way... Gonna have to do some more work to figure out what happen. The pictures before are of the first one.

www.ksu.edu/ksupc/images/tube1.jpg
www.ksu.edu/ksupc/images/tube2.jpg
www.ksu.edu/ksupc/images/tube3.jpg
www.ksu.edu/ksupc/images/tube4.jpg

<--- See look, pink dolphins DO exist!

[TheMonkey 0]

finished construction of one with a friend and jumped this past weekend....need to taper the top of the tube more, but fairly good effort our first (the real first attempt doesn't count) attempt....

---------------------
Never argue with an idiot, they will drag you down to their level and beat you with experience!

[meridianjumper 0]

Quote

NO VIDEO of the highway test?????????????????

Here is my road test! I just completed mine 2 days ago.

http://www.thejumpershack.com/tubetest

Blue Skies,
Jeremy

[Kris 0]

That's a great looking tube, Jeremy! What's the diameter on that bad boy? It looks like it's a fairly good size.

Sky, Muff Bro, Rodriguez Bro, and
Bastion of Purity and Innocence!™

[meridianjumper 0]

The bottom diameter is 2 feet and the top is about 1.3 feet. Total length is 12.5 feet.

Blue Skies,
Jeremy

[kansasskydiver 0]

did you use a similar device for the bottom as i did? did it help you guys any in the design? be curious to see how you built your base and handel. after making more jumps on my tube I have found that a garden hose wasn't hte best thing to use for the ring as it now has a crease is in and won't keep it's shape. back to the drawing board i guess

<--- See look, pink dolphins DO exist!