pchapman 279 #1 November 19, 2015 I can't recall, is there a name for a student system where there are cutaway cables on the cutaway handle as normal, and cutaway cables on the reserve handle too? Where the risers have a double ended loop, each end being pinned in place by a cutaway cable. The idea is to retain the advantages of the SOS in that any handle pull by a dumb student is a correct handle pull for dealing with a mal, while still allowing using the TAS training to pull both handles, reducing later transition training. (Of course a handle pull at too low an altitude is wrong on any system.) Who does or has made such systems? I know Flying High in Canada has done rigs like that on request, but does anyone know some history? Such rigs are fairly rare. Quote Share this post Link to post Share on other sites
LavaLady 0 #2 November 19, 2015 DOS - Dual Operating System. Used by a few operators in Australia. Has come in handy a few times when a student has executed their EPs (handle pulls) out of sequence. For eons in Oz only the SOS was approved. The DOS method was introduced as a trial well over a decade ago, and now TAS is also approved. Systems in use here with the DOS (according to reports received through APF incident notifications) - Javelin, Telesis, Icon. Likely, on request from the manufacturer. Quote Share this post Link to post Share on other sites
mark 107 #3 November 19, 2015 Sunpath offered dual release at one time. Mark Quote Share this post Link to post Share on other sites
peek 21 #4 November 19, 2015 pchapmanI can't recall, is there a name for a student system where there are cutaway cables on the cutaway handle as normal, and cutaway cables on the reserve handle too? Here is a thread where various names are used. It is worth skimming. If it is too much to read, start with Rob's comment in post #16. http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=2837229;search_string=universal%20cutaway;#2837229 Quote Share this post Link to post Share on other sites
riggerrob 643 #5 November 19, 2015 Popularly called "Double Action." First time I ever saw DA was (circa 1995) when Parachutes Australia sent a prototype to Rigging Innovations. PA wanted RI's approval before incorporating the RA system into the Student Talons (they were building under license from RI). My first reaction was "too many moving parts. Personally I think DOS are an overly-complex solution to a minority problem. The risk of first-solo students pulling handles out of sequence has dropped dramatically since tandem became the norm for first-timers. Now they have gotten the first, huge adrenaline dump out if their systems, solo students are better able to focus on pulling the correct handles in the correct sequence. DOS Tolerance are as tight as Single-Operation System (SOS with 3 cables attached to reserve ripcord handle. I am just thankful that I have never needed to manufacture any if those @&$)(?! little double-ended loops. In have seen DOS manufactured by: Altico, Flying High, Sun Path and a defunct company on Alberta. Quote Share this post Link to post Share on other sites
Alexg3265 0 #6 November 19, 2015 dolphins were like that... "universal handles' i think they were referred to... maybe the triton which is its replacement may be set up the same way....?I was that kid jumping out if his tree house with a bed sheet. My dad wouldn't let me use the ladder to try the roof... Quote Share this post Link to post Share on other sites
billbooth 10 #7 November 20, 2015 Two of the reasons UPT never offered this system are; 1. The double ended 3-ring loop drastically increases the chance that the 3-ring will not release when the handle is pulled, for several reasons. We learned this from malfunctions on double ended loops on 3-ring drogue releases. This was one of the main reasons the Sigma Tandem System was developed. 2. If the 3-ring system jams up for any reason, you can't pull your reserve ripcord can you? (Unless of course you add a second reserve ripcord, and students have enough trouble with just one handle.) Even if it is not a total jam up, your reserve pull will be harder because you are pulling 3 cables through 3 housings, instead of just one, as with a normal ripcord system. There are others, but these two should do. Quote Share this post Link to post Share on other sites
pchapman 279 #8 November 20, 2015 billbooth 1. The double ended 3-ring loop drastically increases the chance that the 3-ring will not release when the handle is pulled, for several reasons. We learned this from malfunctions on double ended loops on 3-ring drogue releases. This was one of the main reasons the Sigma Tandem System was developed. There's no major geometry issue, is there? Haven't thought about it in detail. Certainly there is the misrigging possibility, although it isn't like tandem drogues being hooked up every jump. A sewn double ended loop would be stiffer though. Thanks for adding to the thread Mr B., and for the pointers everyone else. Quote Share this post Link to post Share on other sites
johnmatrix 21 #9 November 23, 2015 We still have a bunch of these Javelin Student rigs in service at my DZ in Australia. Quote Share this post Link to post Share on other sites