Carrying on here a discussion that started and currently ongoing on Dropzone.
To Gus: don't use the setup of your second photo!!! In that way, to break the break cord loop (that needs in absolute a force of 96 lb - 44 kg), you need to apply 96 lb - 44 kg to that branch containing the break cord loop: to do that, you need to apply 192 lb - 87 kg to your bridle. Doing like your setup, your body-your harness-your risers-your lines-your parachute-your bridle need to apply a force of 192 lb - 87 kg to break the break cord loop: TOO MUCH!!!!!!!
To nicknitro71: Your simple setup is just like mine (see my photos) with the difference that in the loop of your break cord, beyond the two loops of your C.W.Y. (Carry With You), you must include also the loop in your bridle (where PC is attached), otherwise, doing like in your photo, you end up needing 192 lb - 87 kg to your bridle to break the loop: TOO MUCH!!!!!
To K - K763: Yes, I saw the bridle extension and relevant setup as per Apex's website. Very mice and smart way of doing a SL jump. But. Your setup would leave EVERYTHING (Static Line + Carabiner) onto the handrail/object, thing that: 1) either you don't bother to loose and to be noticed by guards/general public/whatever; 2) or you must go up to exit point again to recover everything.
Nothing against the above, but my CWY (Carry With You) setup was born with something different in mind: NOT TO LEAVE ANY TRACE BEHIND AFTER THE SL JUMP!!!!!!!!!!!!
My setup was born after few discussions with Dexter, and then I received a very precious hint by CRWPER, who suggested me to tie my C.W.Y. to my (special) bridle with a break cord loop (instead of larksheadknotting it onto my bridle as I thought of doing firstly): in case of a (possible) hangup of my C.W.Y. on structure, C.W.Y. itself would be released breaking the break cord loop.
Comprising with break cord loop n° 3 loops (n° 2 loops belonging to C.W.Y. and n° 1 loop to bridle) you end up needing the "standard" 96 lb - 44 kg of force for breaking the break cord loop.
The "explanation" of the 96 lb - 44 kg is the following: we are using a calibrated 80 lb - 36 kg break cord, it means that in a laboratory if you put a single line of break cord in the "jaws" of a dynamometer, you end breaking it at 80 lb - 36 kg (plus minus a natural tolerance). If you do a loop with above break cord, now you need (theoretically) 160 lb - 72 kg to break such a loop (the loop contains two branches of break cord, each needing a force of 80 lb - 36 kg to break). But you do not "close" your loop with sewing or other very smart method, you "close" your loop with a knot.
ANY knot weakens the cord itself (=failure of cord would happen in correspondence of knot).
Doing the surgeon knot we all do to close the brak cord loop weakens of 40% the break force of cord itself (Dan Poynter manual, I have been told), so we are left with 60% of breaking force: our break cord loop would break at 0.6 x 160 lb = 96 lb - 44 kg. A good value for our SL jumps: high enough to withstand with opening forces required by container/velcro/pin/whatever, accelerations/whatever, low enough not to cause problems to the opening of parachute/integrity of bridle/harness/whatever.
So, to make short a long story: Apex method is fantastic, but my CWY SL setup is aimed basically (and only) to not leave any evidence on exit point, in rder to have NO NEED of returning to exit point to pick stuff left behind.
A word about the photos I posted here: it cannot be seen, but my setup includes LEAVING THE PC ONTO THE (special) BRIDLE, where bridle loop (with PC attachment) is something like 1 ft - 30 cm beyond that knot you can see (knot been passed through by break cord loop), so there are still 9 ft - 2.74 m between PC attachment and pin (or shrivel flap).
Just my 0.02.
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