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phorty

Cutaway cables

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Hi everyone,
I exercised my three ring release system today for the first time on my newly aquired rig and noticed that the cable clears the loop on the right risers before the left side does. In fact there appears to be another couple of inches of cable to go on the left side when the right side releases. I thought that all the rigs releases were custom made and as such should release at the same time for a stable chop and reserve deployment. What do ya'll think? Should I have my rigger correct the problem before I jump it again(which could be a while) or ASAP? Thanks!

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This may be a deliberate design feature.
If your rig is designed to have an RSL on the left riser (even if there isn't one fitted now), then the right riser should release before the left one.
2 inches sounds like a big difference, though - as always, it's best to check with a rigger.
Geoff

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Geoff is right. The RSL riser should release last. Your rig is fine! He is also right about the cutaway cable length being custom fit to each rig. I know that Javelins and Vectors are built that way. Of course, if you lose your cutaway handle and replace it with a new one, you may have to trim the ends to get it to fit correctly. Your Rigger can do this for you with a pair of cutters and a lighter. Kudos to you for being that observant!
Respectfully,
SP

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Yes, you want a guaranteed first right side release first with an RSL in use.
In my mind with a two inch longer RSL side cable, along with an aggressive pull/cut away, would translate to about a 65 ms (1/16 sec) second delay after the right side. (I'm assuming a two inch difference (0.166 ft)
Anyone want to make a guess how far the right riser ring is above the harness ring when the left side releases? (assuming an aggressive pull/cut away)
Dave Brownell

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This was a quicky calculation assuming no relative speed difference, i.e how far would you fall from rest in 1/16 sec?
10 m/s^2 * (1/16)^2 = 0.04m
I would guess that there is some additional upward force (drag) from the canopy, and possibly some angular momentum/centrifugal force if you are spinning.
I am not a physicist, nor do I play one on tv.

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Quote

But he did stay at a holiday Inn express last night

Damn, beat me to it!
Seriously though, I am GUESSING about 12in released riser travel as the second riser is being released. I noticed the differences in the cable lengths (from loop to end of cable) when I was inspecting my release system a few months back and chalked it up to design and wanting the RSL side to release first to possibly reduce the risk of reserve PC entanglement. Another consideration besides wanting the RSL riser to release first would be housing flex/strech due to a loaded harness. This might or might not be equal depending on the mal (more weight suspended under the RSL side would strech the harness/housings more on that side which would use some of the cable length as a result. FWIW my RSL side release cable is 1 1/4" longer than the other side.
Craig

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Craig said:
Seriously though, I am GUESSING about 12in released riser travel as the second riser is being released. I noticed the differences in the cable lengths (from loop to end of cable) when I was inspecting my release system a few months back and chalked it up to design and wanting the RSL side to release first to possibly reduce the risk of reserve PC entanglement. Another consideration besides wanting the RSL riser to release first would be housing flex/stretch due to a loaded harness. This might or might not be equal depending on the mal (more weight suspended under the RSL side would stretch the harness/housings more on that side which would use some of the cable length as a result. FWIW my RSL side release cable is 1 1/4" longer than the other side.
Craig
DB> You do mean the "non" RSL side, ideally releasing first.
I would agree with 12" - 36" being a riser release difference figure.
Dave Brownell

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"What do ya'll think? Should I have my rigger correct the problem before I jump it again(which could be a while) or ASAP? Thanks!"
phorty,
You or your rigger should contact the manufacturer for the correct specifications for the cables and how to check them properly. It may vary from manufacturer to manufacturer. My advice would be to do this before jumping the rig.
Be safe,
alan

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i'm not sure how the tso reads on certain rigs. but i do know that the reserve ripcord is a tso'd item so the cutaway may be as well. master rigger only...and even then it's kind of a grey area... contact manufacturer and find out if the tso applies to that specific part.
blue ones

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i checked on yer question today...apparently the cutaway is NOT a tso item because it is not directly related to the reserve system itself...however there is a delay on one side(the rsl riser) so that the last thing that happens in the sequence is that the rsl gets pulled as the main canopy goes away...if the order were reversed there is a chance of the rsl pulling too soon and the reserve pilot chute deploying into a bad main canopy...
hope this helps
blue skies

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