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Is it recommended/not to use multi bridle on terminal? I assume it wouldn't be a problem, and I couldn't find anything advising against it. I am not talking about off headings as the use of the multi is debatable, just anything severely dangerous and obvious that I am missing.

Secondly, if you can use the multi for terminal, does anyone have experience with it for wingsuiting? I assume since the multi ads 2 feet to the bridle length, you don't need to use a 11' wingsuit bridle, right?

Thanks in advance.

go back skydiving, [xxx]boy.mayby you'll understand the dynamics, not just try to learn what the features do.
first, the multi was designed more for terminal deployments.
second what use is the "2 feet" for a wingsuit deployment when they are located after the pins?
who uses a 11 fott wingsuit bridle?



edited to remove what could be construed as a PA -- wwarped

edited to edit that the edit did in fact edit what was construed as a pa. thank you.

Multi is a old wives tale...who jumps a multi...i have packed a few of em but they just take extra time to pack...

extra time my ass, ive seen you pack a base rig in 15min! i guess its different when you dont have to jump it =D

did 2 pack jobs down in 33 mins that night...

from now on i am only packing for your jew ass...hahaha have a good hanukah or whatever the f@#k it is..

This is your best post yet. Reading it i cringed for you.

I'll be sure to get video.

The multi is best used for terminal.

If you have not yet accelerated to the speed of a crosswind, the side attachment on the upwind side will load first, potentially spinning the canopy as it is extracted from a non-centered bridle attachment. This can cause offheadings and line twists. As a result, I would not recommend using the multi on any slider down deployment in a crosswind, and I would be hesitant about using it on any non-terminal crosswind deployment. A wingsuit deployment would be close to the ideal situation for multi use.

The multi does not change the length of your bridle, as the relevant measurement is the distance from the PC to the pins/shrivel flap, and the multi is placed between the canopy and the pins/shrivel flap.

If you have a multi-equipped canopy and are considering sub-terminal use, I'd recommend either removing the multi entirely (simplest solution) or removing the outside multi attachments (leaving just the two attachments on the center cell--the standard location and the one lower down by the tailpocket--in place).

Thank you very much Tom. I appreciate the help.

I didn't even think about what the relevant measurement was in terms of lengthening the bridle, but that makes sense. Would you even recommend getting the 11' bridle then? I have heard it's pish posh as well if it helps any. I'll be doing alot of slider down and plenty of ws jumps, so if I don't have to keep changing the bridle I'd rather not.

I haven't actually seen much difference in using the 11' bridle, but I wouldn't say that the evidence is conclusive either way. Personally, I've always used the 9' bridles for wingsuit flights and haven't had any issues. I can't see any problems with using the 11' either, though.

If you are doing the loads back to back (wingsuit and non-wingsuit), then I'd probably go with the 9' if you don't want to change. If the loads are done at different times (for example, you jump a bunch of slider down stuff at home and then occasionally take multi-week European trips for wingsuit flights), I'd probably get an 11' bridle for those trips, because you'll only need to switch at the beginning and end of the trip.

Changing a bridle out is really only 30 seconds of work anyway.

video of what?

the wingsuit?
the multi?
the 11 foot bridle?
the "2 feet"?
your junior size member?

i'm a little confused here.

Of him being awesomely cool

I jumped a multi Vtec canopy on about 400 jumps. terminal all the way to half second delays. worked great for me. i almost never, ever had anything but a perfect opening.

++1.
You rock dude.
Take care,
space

Ive used a mutli for SD & WSB and have had perfect openings except 1 or 2 off headings of no more than 45 deg. Will be getting one on my Flik UL :P T

+1 Although I will admit I dont have very many light delay jumps with strong crosswind. I always consider taking it off just to experiment, but I never have gotten around to it.

I havent used a mutli for and have had perfect openings for over 20 yrs (except for 2). What issue are you trying to address withe the multi? Iffin it was great, all would be using it.
It is your psychological well being before the step off rather than the logical that is important. Unfortunately, psychological is not logical.
Go for it dude.
Take care,
space

What part of PA are you in? I might be passing thru. I'm bringing my rig with me and I want to jump some new objects.

i need to learn your gear configuration and your packing method space if you are doing that well.

I have around 1600 jumps with multi, and around 100 without, 99% terminal jumps. I didn't find any big difference in the heading without multi, but i found a difference in the regularity of the openings. With the multi, the openings have always the same "tempo", and my FOXs are like a swiss coucou (clock) ... good if you fly a bit low

Multi rules !

I see different points in here regards to multi preferences.

So multi helps(or worsens in crosswind openings as Tom alludes) in heading performances or to reduce the wear (one point attachment would have more stress/wear on the attachment point than a multi point attachment on the canopy, me thinks)and the smack on openings?

I never jumped a multi but just curious why multi came and how it performs against single-point bridles

PS. am learning

I believe the original idea behind the multi was to help alleviate center cell stripping.

Center cell stripping occurs when the center cell is pulled tight to line stretch, but the other cells are not tight yet. In theory, this happens because the bridle is attached to the center cell, so that the center cell is pulled to full line stretch first. When the center cell is at full (tight) line stretch, the outside cells are still lagging behind a bit.

There are a couple hypothetical problems with this:

1) The center cell lines are tight, but the other lines are slack. Personally, I think that with a good locking stow, this isn't really much of an issue.

2) The center cell being pulled out of the pack job deforms the pack job itself, which can lead to other problems with inflation such as offheadings or potentially much worse things (line over or tension knot). While I can easily see the problem here (I have some good video of it), I have yet to see a case in which it's been well documented that the center cell strip actually caused a malfunction.

The multi is intended to help alleviate center cell strip by distributing the bridle's pull force along all three center cells, extracting them simultaneously.

If memory serves, in the course of the multi's development, Basic Research shot video of the canopy topskin during deployment and noticed that the tailpocket was slumping between the lines and inverting (they saw a flash of the bottom skin color at the rear during inflation, I think). They then added the fourth (tailpocket supporting secondary line on the center cell) multi attachment point. I can't see any downside to having this attachment (and there are some real potential advantages, like eliminating line burns that tend to accumulate on the tail, especially on 5 control line canopies).

Bottom line, for me, is that in cases where your body has accelerated to the cross wind speed (especially at terminal) the multi can only help you. At lower airspeeds, the outside multi attachments can create real issues.

I have only about 400 jumps on a multi-equipped canopy, and although I own two of them I have removed the multi's, mostly because they are in service for First Jump Courses and I prefer to reduce the complexity that students face in packing the rigs.


Side note: If you are using a multi, I would recommend against using the black rubber bands to stow the multi at the top of the pack tray (for a while BR was including these bands for that purpose--I am not sure what Apex does today). I know of at least one case in which a low airspeed (slider down) deployment experienced a substantial hesitation after container opening because the multi was temporarily held in the black rubber bands, towing the pilot chute.

I talked to Todd last week they just s-fold the multi on top of the pack job these days, and if you get a new container for a multi canopy, they do not install places to make stows on the container.

That was Todd's original design. He added the stows because people bugged him to make something "neater." Good to know he's gone back to the original, simpler design that never had any problems anyway.

That's some good, detailed post there, Tom! Thanks for that!! The explanation made it easy to imagine the opening sequence in both the cases.



....I like simpler things unless I have to choose otherwise. I will stick to the single attachment system. Don't want to bother myself with the S-folds or the extra stowing :-)

On another point that occurred to me while reading your reply - line burns : The Dagger I jumped had the tailgate pocket sewn right along the edge of the tail. But in a fellow jumper's Flik, I see that the pocket was a bit on the upper side, thence leaving some part of the tail exposed (to line burns). I couldn't think of any rationale for upward change exposing some fabric to the lines. Is it the norm these days for some reason or was it just his canopy?

Different manufacturers/designers simply made different decisions on this issue. The Dagger (Vertigo BASE Outfitters) is built with a small tailpocket and a locking stow at the bottom. The FOX/Flik (Basic Research) has a much roomier tailpocket and a locking stow hiding way up under the pocket. The Ace (Consolidated Rigging) is somewhere between on both counts.

The idea behind pushing the locking stow further up inside is probably that if the rubber band fails the gap between the pocket and the canopy will act as a secondary locking stow (holding the lines in place until line stretch).

Another way of working toward this same end is to use a tighter opening (as you will see on a Dagger, or especially on early Trolls, which had very small openings for the locking stow to tuck under the pocket).

There is really no "norm". Different canopy designers/manufacturers simply made different design decisions.

I specifically asked Todd about the tailpocket location and he told me that testing/history had shown that there is not a wear issue there and moving the tailpocket up a bit is purely a manufacturing thing. It's much easier to place the tailpocket there than to keep multiple layers of fabric all aligned together during assembly.

Plus, it's easier to replace/repair when needed.

Are we talking about the location of the pocket itself, or the location of the stow behind the pocket?

The reasoning behind moving the pocket itself up away from the tail seam.

o yes, I did notice that (unusual, then for me) tightness in the locking pocket of the Dagger.
That secondary locking idea when the pocket it moved a little inside is something new I come to know now. Good I asked. I get more related information from you :-) Thanks!

And I was actually wondering about the location of the pocket itself w.r.t to the actual edge of the tail. Freak seems to have had the same question and indeed got a satisfactory answer from Todd. That explains it very well. However it surprises me that history/testing says there is no wear on the fabric ..which was my main concern. Whatsoever, I settle my doubt with what I read from you two.

And that easy repair/replace makes such perfect sense too.

Does it? If so then why do Apex re-inforce that area with several extra layers of fabric?
They moved the tail pocket off the tail seam for no other reason than easier manufacturing.