Basejumper.com - archive

So theirs a fair bit of discussion about how to make static line jumps with presumable a single canopy pin rig. Inerter of the canopy. Required break force of the tie off. Back ups for the tie off. Etc.

Just to be clear. I'm not a low jump guy. I've actually never done a static line or a PCA. I have PCA'd people off objects so that they could have more canopy time and then wished there was some one to do me, but the point is I've never jumped any thing where I had to have a PCA or static line. So I am kind of talking out of my ass here.

What amazes me is that no one seems to do D-bags. Or at least no one seems to be discussing it as an alternative to static line for these low jumps. There has actually been discussion of static lines done with out PC's because they needed the performance to reach the landing area. It just seems that people are trying to force these single canopy pin rigs into this role. I don't see them as being well suited to this. It's not really a good design for supper low jumps. Think abut it. You're falling away from the object but still very close. You're hard pointing this canopy from a single point. And yanking it out of the container, not at a high speed but with a sharp stop not a gentle continues tug of a PC. And then your body continues to fall at a relatively slow speed till you hit line stretch. So you've got a sharp extraction, potentially prone to turning the canopy especially if it's even slightly to the side, and then a good bit of time till you hit line stretch for the canopy to rotate and it's all happening right by the wall. I'm surprised it works as well as it does because I don't see it as being the best design in the world.

Has the idea of a Direct Bag just completely died out. And if so then why? I'm being serious. Where is the down side? The canopy is held straight on heading in the proper orientation. It does not have any opportunity to turn as you fall to line stretch. It can be held out away from the wall or railing or ledge. That is if the holder can stand there safely. It basically assumes a tie in or safe stance behind a railing for the holder. There is less opportunity for angle between the Anker/canopy/jumper that might sling the canopy around and slap it back into the wall like when you hit line stretch and the break cord pops like on a static line. And the canopy is clean. No PC dragging. I don't see the bad. And with the bad ankered and perhaps a lite break cord or rubber band in the top of the bag to the top of the canopy to extend it I don't see how you could have an issue like the last fatality.

Is it so old school that no one does it any more? There are a lot of new people in the sport. Did the idea just get lost in between generations? Is it just that no one owns a rig with a nice wide bag that would fit your canopy? Or are there other disadvantages that I just don't know about?

In any case I think I owe beer as I believe this is my first attempt at a poll. The first option is to see how many people actually jump these low objects. The others are to judge whether this is still in use. Feel free to write in how silly D-bags are and all that is wrong with them.

Lee

If I had to guess, I'd say its because:

1) theres more gear to buy/make/fuck about with.
2) theres more setup/rigging involved
3) if you have it packed up in a dbag and then dont jump it then you have to repack/reconfigure. with a static line you can just remove the knot/staticline and then youre ready to freefall.

In general, laziness and a lack of fucks for the advantages.

Im going to be using one soon. For ultralow solid objects it just seems silly not to and I dont mind fucking about with the gear/extra hassle.

Also, while we're on the subject...whats the lowest B anyone has heard of being jumped?

https://vimeo.com/113620355
Still happens, just not always because it's a low jump
Notice the pilot chute on the D-bag - just in case.

Adding another person to your jump adds a variable that you cant control. (heading is determined by holder). Ive seen many experienced jumpers who cant PCA correctly.

2 people required for one jump. If they are both jumpers someone has to SL or not jump.

From the little research ive done, height difference between Sl/Buddy bag is negotiable. IMHO adding a human variable doesnt add any "safety" to the jump

6:15 Buddy Bag 180 with strike.

https://www.youtube.com/watch?v=Q8GXt6im2mM

Shit man, uncool to the max man... way uncool man, Im pissed at you man. Shit man fuck man.

Really cool video. What was the date on that? Looks mid 80's ish. I wish I could see a little better. It's hard to tell what is going on with the extraction of the canopy from the bag and the inflation. I wonder how it was packed? I'm thinking there is a good possibility that the canopy may have been "Stack" packed rather then "Pro" packed. I'm not sure how far along packing techniques would have been at that point. It looks like it was at least 90 deg off heading right from extraction. They commented on the wind but it's hard to tell how strong it was.

Lee

Yeah, I was thinking it had something to do with packing instead of the holder. Seemed like it was already at 90 degrees right out of the bag then turned abruptly the other 90 maybe with help from the wind. Or maybe it was a line over..... or maybe it was just the O-rings like was mentioned.

I thought I heard them say something a bit later in the video that they may could attribute the flakiness of the opening (i.e. continuation of the offheading from 90 to 180) to a common trend of flaky openings they and people they knew were seeing with cruiselites... if that helps at all.

I may be wrong, but that was what it sounded like at one point.

Yeah, that's what they said but I'm not convinced it was only the type of canopy that caused the off heading. It's hard to say from the video exactly what happened.

Im pretty sure they just used a standard skydiving dbag in that old vid lol

How difficult would it be to set up a solo D-Bag? I'm thinking the biggest problem would be maintaining the orientation, but other than that, just tying it off to something would be fine, no?

I know it sounds like a silly question, but there is a low B I'm considering that most BASE jumpers couldn't get access to (and those who could probably wouldn't want to do it).

at that point, it almost sounds better to go to a bridge and practice tards and do that off it... solo Dbag sounds like a bad idea already. Maybe just duct tape a walmart bag to the edge of the B, take your packjob out, put it inside the walmart bag, jump. You're essentially doing a jerk off... like you could just do a topskin assist or lay your canopy out on a piece of tarp for abrasion control and jump off and pull it with you, but don't let that stop you... hell, you might as well ground launch it off the B, you have running room?
Yes, I'm being a little sarcastic

Haha, I've actually considered all of these, except the tarp one. It's certainly never been jumped. Ground launching would feel a bit like cheating, and I'm concerned about heading performance for the TARD, although that was my original plan.

I've though about how you could set up a solo bag and even how it might be improved in terms of heading but it's so very dependent on what you're jumping off of. What are you going to ancker it to? I think this is really kind of the down fall of the D-bag and the reason static line and carry away static line have taken over.

Lee

I remember reading this thread a while back on SL vs D-Bag. http://www.basejumper.com/...atic%20line;#2312576

Mick Kellaher took a solo d-bag off the top of the Sydney Harbour Bridge from the top in the late '80s.

He had the d-bag duct-taped flat to the wide steel girder and stood over it to launch off.

G.

I'm not sure about the anchor yet, as I haven't actually been to the exit point. I have walked the landing area heavily though. I have easy roof access, but getting to the exit would entail some rappelling and then ascending the fixed rope again. I just haven't gotten around to it yet. I plan to walk the exit point extensively before jumping.

There will likely be tie off points available, but in any case I could bring a significant amount of weights up there to be the anchor.

So you went from just wanting to gain knowledge about BASE and help with ground crew 4 months ago, to getting a new canopy 1 month ago and now you are contemplating what sounds like a low technical jump where you want to bring weights to the exit as anchor points for a DBag setup that is far from the norm and untested by you?

Sounds like you are progressing.... Jedi.

I've done a handfull of solo DBs in the early 90´s. But only on A`s where tying off was easy.
I will write more when I have time.
Take care,
space

I probably deserve a little scrutiny, but I think it's a little less low and technical than you are imagining. It's more the particular intricacies of the object that make a D bag very useful. I (mostly) got my BASE canopy to practice in a skydiving environment. And who said I wasn't going to test it?

I'd honestly like to know what you think about it and will PM the details if you'd be willing to give me your thoughts.

I was thinking you weren't testing the DBag setup not your canopy. I would hope you have already thoroughly tested that!

PM me the details and I'll tell you in private you are crazy! Hahaha, JK!

Im curious what about that particular object makes a D Bag more useful than a SL?

If you have roof access to a not jumped B, why don´t you just invite some of the experienced guys in your region to join you and jump it together with them? I´m sure if the B is even half decent jump, there will be plenty of guys willing to join you and show you how it´s done and also in the process you might make some contacts from whom you can ask this stuff in future (instead of trying to get some info online). Dwain wrote in his article "getting into BASE" :

If you seriously want to get into BASE then you should try to give to the sport before you take from it. This is a sure-fire way to be noticed by the experienced jumpers. Some suggested ways to give to the sport are:
- Discover a new site. Discovering a jumpable cliff (edited to add : or a building) is one of the greatest gifts you can give to the BASE community.

That's what I meant, I will be testing the D Bag


Below the point of impact is a road which, if cleared, has a significant drop off that would give me more time to set up a landing. Clearing the road is doable with a static line, based on relatively conservative estimates. However, if I can increase my safety margin, I would prefer that. Detensioning the lines if I landed on the edge of the road would be dangerous. Specifically, I related it to this:

http://www.blincmagazine.com/...iki/Ueli_Gegenschatz


I wasn't trying to get advice for the object online. I just wanted to know if anyone had any ideas for a solo D Bag that they would like to share. I don't intend on doing this without getting some pretty heavy consulting from outside the digital world.

If you are concerned with Clearing a ledge on a low object you should probably just walk away. For the sake of this discussion you should at the very least do what Maretus says and take a few experienced jumpers to the object and have the discussion in person with them.

Im not convinced a D Bag will give you that much more margin than a SL. Add in the complications of securing a D Bag to a weighted/movable anchor point and retrieving it after the jump, you are increasing your chances of something not happening exactly like you need it to happen. and if you need that much more margin then......

Do 50-100+ Base Jumps then revisit this scenario and you may find your opinion on "Doable" has changed.