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Hello guys
I would like to have some opinion concerning the "jump in sub-terminal " conditions.

I have some "theories" taken from packing video indications, some experts suggestions and more... and I would like to have just some extra info from you too , if possible.

Sub-terminal jump, around 5 second delay , jump with slider up ...

About the packing ,
- noses rolled up or not ? ( rolled noses, or looking inside for soften opening)
- slider with robber band or not ? (allow a better line extraction if used)
- body position "in tracking" style or box ? (better air flow to the canopy if tracking)

As far as I understood , these three elements should make a nicer opening but without a real impact on the time needed for it.. but as mentioned, this is "theory" :)

I have also to say that I am using a nice cool FLICK 354 :), 4 vents ...
from here , in your opinion, I should consider a bit more time for the opening compared to a smaller canopy, or "it doesn't really matter because all is proportional" ?

Thanks for all the hints you may provide :)
3...2...1.....Ciao :)

Sub-terminal jumps from solid objects are the most technical jumps, according to the experienced people in the sport. Ask your mentor/instructor in first place.
Then, just as example, I think you should consider the whole picture. If you are planning 5 sec from a 300 meters bridge is not as if you're planning 5 sec from a 280 meters cliff with a tigh landing zone...
Generally speaking in a 5 sec SU jumps you want a really fast opening and a perfectly oh heading opening too (unless you are a track monster dude).
So work on the elements of the packing that guarantee that two standards (e,g.: body position depends on your experience vs direct slider control is a matter of fact). And get the proper PC!!!
Then consider is something goes wrong...There was a video discussed on IBA forum in which a jumper did a SU from the famous Greek cliff and pulled after 2 secs. Shitty opening obviously but fortunately he hanged on the cliff and rescued without injuries.
So, do not under estimate those kind of jumps.

Nose: Medium roll, not too tight.
PC- 38.
No direct control on the slider.
As for body position, unless you are very experienced and this is most comfortable, I wouldn't bother trying a slick track. Just go box or whatever will keep you most stable.

That's what I run off a 5sec slider up cliff here and it works well.
Good luck!

If you were one of my disciples, given your size,
corresponding larger parachute (FLIK-354), and
the fact that newbies usually err towards under
delay, I would have you use a vented 42" PC.

FYI: taking 5 seconds from 640 feet is scary,
taking 5 seconds from Brento would be easy.

Fair enough, I'm sure it does work for you - but what's your logic in rolling the nose at all?

Definitely true.

The slower subterminal opening, combined with the slider up configuration, shallow brakes and the limited separation due to short delay mean that solid objects in the 4-7 second range are some of the most dangerous jumps most of us will ever do.

There will always be personal preferences here, but mine are:


Nose rolled symmetrically to the sides, with the center cell exposed.


Yes. I'd use both direct and indirect slider control. Out of sequence slider deployment will still ruin your day at 5 seconds.



Track as if your life depends on it. Because it does.




A bit more time. But pitch as low as you can, because it's very important to establish as much separation as possible, and every fraction of a second helps.

I think in subterminal SU jumping this is the most important advice you can give and it is the key to survival. The cleanest packjob of all times with all bells and whistles will not save you if you dump too high right next to the wall because random shit will happen. But if you take it low enough you can get away with all kinds of stuff. Remember, given that there is a talus with trees underneath the wall, it is WAY better to land into the trees with a 180 than hit the wall.

I personally have a rule for myself that I will never jump a solid, slider-up object with a 4-7 second delay. I'm not interested in the extra off-heading risk. That said, I am interested in this conversation for academic reasons. A few thoughts and/or questions below. Let me know if I'm wrong here, and if so I'd love to be corrected.


I would think you would want the nose wide open to speed up opening as much as possible. Slider-up off headings are largely a function of the extra time it takes for the canopy to pressurize/snivel, no?


I use the primary stow (indirect control) on all jumps, period. On terminal jumps, and especially tracking terminal jumps, I use a LOT of direct control. I'll wrap it 3-4 times to slow my openings since I've been slammed on terminal jumps before. Given the situation at hand, I would think less direct control (fewer wraps of the rubber band) would be appropriate to speed the opening a bit. A couple wraps would still help to stage deployment though.


Tracking. Always tracking. Get far, far away.


I jump a much smaller canopy so I have no idea what specific PC size would be right for you. But for me I would upsize one PC level, again in the spirit of a quicker (hopefully more on-heading) opening. And to an earlier point, to account for a shorter-than-planned delay.

Interesting discussion. Thanks for the post.

I would say yes in a way. It also has to do with the time it takes the slider to make it's way down the lines which is directly tied to the time it takes the canopy to fill with air. The faster you can get the slider to come down the less time the canopy has to search for a heading. If the slider takes a long time then wind or small weight distributions in the harness will have a much more dramatic effect on the heading. I would deploy in a track and take the longest delay possible to increase air speed/flow to the canopy. I would also only use a single wrap indirect stow and open the nose with no rolls.

5 sec slider up solid object, that is for me the worst combination for heading performamce I would avoid that.
If I had to jump, it would be for fastest opening possible, nose fully exposed, no direct control of slider, lowest pull possible.

Hello guys,
Really many thanks for all the hints , I appreciate and evaluate all of them... I really like this forum because there is a high level of participation, great.

About heading , from my experience, the body position really matters, and has an impact on the heading... But is also interesting to read the different point of view about noses , slider control and so on...again, thanks :)

I will make some tests from a balloon , just to experience some of the hints given , of course keeping in mind that 99 jumps can be just perfect while the 100, even if apparently done in the same way of the previous can be totally different...

Take care mates

Taking 5 seconds out of a balloon at 3,000' AGL with zero strike hazards around you and the inability to experience the ground rush is a whole different ball game than taking 5 seconds off a slider-up, sub-terminal, solid object and watching the trees you are about to impale try and poke you in the eyes. Still better than nothing though.

I'll bet you count a little faster on that solid object jump ...

i might suggest going slider down 4 seconds and take the slammer. you will prolly pull then anyway

Personal preference.

 

yes of course you are right , but I want to test the canopy opening given certain conditions: noses slightly rolled, slider with soft direct control, heading, opening time...
:) rookie stuff :)

go to France where you can practice from Millau or if you really want a solid object behind you go to LB valley, Gimmelwald exit, its overhung and you can even track it for a slight second before you pitch. its one of my fav exits in the valley, SU and SD shit

yildiz

Was thinking exactly the same.

this. for sure. we have something here thats beautiful, but for fucks sake, if you pitch too early, you may end up in a world of pain, donny. it goes from being a hair positive, to finally getting negative after you pass the 4 second shelf. i hate this fuckin thing. i wish i had giant walls in my backyard, instead of just in my head.

Tested at the weekend -

Nose rolled symmetrically to the sides, with the center cell exposed.

PC - 42 (As i thought i would probably not make 5 secs).

Both direct and indirect slider control.

Box Man.

4.5 second delay.

Worked well.