f1shlips 2 #26 September 22, 2004 QuoteThe term used is: functionaly open within 3 seconds. In typical FAA parlance it looks prety cut and dried on the surface but if look inside the meaning of the phrase it can be interpreted in different ways by different people. Is there a "common" usage that is generally accepted right now? If so, what is it?-- drop zone (drop'zone) n. An incestuous sesspool of broken people. -- Attributed to a whuffo girlfriend. Quote Share this post Link to post Share on other sites
riggermick 6 #27 September 22, 2004 QuoteQuoteThe term used is: functionaly open within 3 seconds. In typical FAA parlance it looks prety cut and dried on the surface but if look inside the meaning of the phrase it can be interpreted in different ways by different people. Is there a "common" usage that is generally accepted right now? If so, what is it? No. That's why I gave the explanation. If you ever decide to design, build and test your own equipment you'll understand just how difficult it can be. More importantly you'll find out just how uncooperative your competitors will be when it comes to getting experienced advice and/or tips on doing things. It's a very small market and these guys are very protective of thier "secret stuff". Been there done that. Mick. Quote Share this post Link to post Share on other sites
mjosparky 3 #28 September 22, 2004 Quote it must deploy in 3 seconds or less after a cutaway. If you don't cutaway, don't count on having a reserve out in 3 seconds. The term used is: functionaly open within 3 seconds. In typical FAA parlance it looks prety cut and dried on the surface but if look inside the meaning of the phrase it can be interpreted in different ways by different people. IE: is "functionaly open" enough to slow you down and damage you a little bit or even a lot? Or does it mean open to the point of no damage to you at all? Both are correct as no clear definition is ever given, but that is typical for the 8015 b and FAR's. I'm just sayin. Mick. Testing to receive a TSO, AS8015-B Minimum Performance Standards for Parachute Assemblies and Components, Personnel, is a lot like jumping. You can do everything right and still be wrong. As Mick said, you can have 5 different people read AS8015-B and get 6 different interpretations. SparkyMy idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
cssriggers 0 #29 September 24, 2004 This is fascinating to me ... mainly because I've seen 16 low main pulls resulting in Cypres fires in the past five years. All resulted in 2-out situations (read - reserve fully deployed. Sometimes quite a delay after full main deployment.) The only time I saw trailing reserve PCs/freebags was on old student gear with large mains (VERY low WLs and slow speeds) and fXCs. Obviously it happens in other situations, and I realize my experience is limited. I believe the incident that Spizzarko referred to is here: http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=1096907;sb=post_latest_reply;so=ASC;forum_view=forum_view_collapsed;;page=unread#unread While this was not an AAD situation, it's food for thought. I'm not saying that reserves will always open in 3 seconds, no matter what's going on. I am saying that I've seen them deploy pretty reliably after a Cypres fire, with the main fully open or in a state of deployment - except in the case of very large student mains and FXCs. I believe speed is a big factor. Above all I'd hate to see people down & dirty --doubting the ability of their reserve to open low if they're really having a bad day -- no matter what's going on with ther main, and no matter what happened in Russia.Alpha Mike Foxtrot, JHL Quote Share this post Link to post Share on other sites
Raistlin 0 #30 September 24, 2004 I'll chip in a bit late, just to say that after the cypres fired, the reserves did not deploy and the springchutes remained loaded, says direct witness to the incident, my instructor. He adds that none of the riggers who packed the reserves are internationally certified, and that while they are blamed for this mal, he thinks it was the manufacturer's mishap... Seeing how the loop cut by cypres locked the flaps, would that flinger thing have helped in this situation? Quote Share this post Link to post Share on other sites
celestial 0 #31 September 24, 2006 Strong in general doesn't really make sense. Having been on the inside.... I don't trust it as far as I can throw it... Quote Share this post Link to post Share on other sites
bclark 0 #32 September 24, 2006 I have seen with my own eyes the reserve ripcord on a Quasar pulled, with a 5 second delay between pin extraction and the pilot chute "flopping" rather than launching onto the floor. This was 4 years ago. Could be the rig, could be the rigger. But i have seen it. The handle was pulled on the ground prior to scheduled repack. Quote Share this post Link to post Share on other sites
riggerrob 558 #33 September 24, 2006 QuoteQuoteHas there ever been a case of a reserve container having the pin pulled and due to the flaps not opening or not opening quick enough that it caused a fatality or a problem? A few months ago a foreign(french?) 4 way team smoked it down and all had cypress fires. However, all of their reserves did not deploy from the Mirages they were jumping. They all realized what had happened and deployed their mains and landed safely. So yes, it has happened. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Eric Fradet has explained this phenomenon in detail. Basically, if the reserve closing loop is too long, it can get pinched between the top of the (spring-loaded) reserve pilot chutes and the underside of a grommet. This pinching can prevent reserve side flaps from sliding apart. This problem has been documented on Mirage and Vector 3 containers. We saw a similar "table total" with an obscure version of the Telesis student main container. The Telesis variant with a spring-loaded pilot chute, two ripcords and an FXC ... all on the main container ... got too complicated. If the main loop was too long and you pulled the reserve-side ripcord, nothing happened. The closing loop got pinched between the top of the pilot chute and the underside of of a grommet. That pinching created just enough friction to prevent the main container from opening. R.I.'s short term solution was to shorten (sorry about the pun) the main closing loop as much as possible. Sandy said that the long term solution was to never sell another Telesis with that main configuration. FXC Quote Share this post Link to post Share on other sites
LouDiamond 1 #34 September 24, 2006 Yes, there was a detailed explanation and it even made some of the magazines.....2 years and 5 days ago in 2004 when I made that post. "It's just skydiving..additional drama is not required" Some people dream about flying, I live my dream SKYMONKEY PUBLISHING Quote Share this post Link to post Share on other sites
Jeffrey 0 #35 September 25, 2006 It appears two different phenomenons are being discussed here at once. One is container hesitation after ripcord pull and the other by means of loop being cut per AAD cutter. I would like to expand a little on a portion of Robs post pertaining to the AAD cutter. I keep hearing everyone’s opionion on this topic so here is mine. At this time two years ago I was only half way through a test program that would end up lasting me well over 6 months. In that 6 month period I compiled a tremendous amount of data after actuating the reserve by cutting the loops of every Mirage I could get my hands on. From the smallest to the largest and that’s a lot. I used 2 methods to accomplish this. One by means of using out of date Cypres cutters generously supplied by Kai at AirTec and the other by building 2 mechanical cutters. I will post photos of them if anyone’s interested, they worked very well. The following data was entered on a spread sheet during each test: Date, Rig Type and Size, Ser #, Pack Job (was graded 1-5), Rigs Owner, Loop Length, Lubricated (amount of silicon was graded 0-5), Cut @ (length loop was cut at from pin), Cutter Type (Manual or Cypres), Duration Packed, Launch Results (was graded 1-5), Plus notes where taken as to the many additional conditions I threw at it to manipulate the results. All cut loops were then bagged separately with an identifying data card and filed. The following is just some of our findings from the program: When the cutter is mounted below the reserve PC and the loop is cut by the AAD cutter, the energy from the PC spring is released and the length of loop remaining from the pin to where it was cut must pass through all the grommets above it. This length can range anywhere from 1.5” to 2.5”. When the cutter is above the reserve PC, it will always cut at 0.75”. The grommets are the major contributing factor to causing this type of heisting or lock. As the remaining loop snakes past them and the grommets reach that sweet spot, they produce friction on the loop in the same exact manner as your leg strap hardware. To confirm this I pounded and even grounded out only the section of grommet that comes into contact with the loop. You can’t lock one up that way. I only wish I could have found a way to manufacture them that way. Something I keep hearing and really bothers me is that it’s all in the loop length. “If your loop is never longer than this, or use a short loop and the potential to the problem is gone”. This is only partially true. We found that it’s not so much the overall loop length, it’s the distance from the cutter to pin and YOU CANT SEE THAT AFTER A RIG IS PACKED. I had some really good looking pack jobs cut the loop on the outside of what I would be comfortable with. I had to cut the loop to a lot of pack jobs to confirm this. Maybe next time I will expand a little on where I feel the location and depth of the failure bar is set for this phenomenon. I hope there is, but to my knowledge AirTec is the only other company to invest more time into this than I have. Also by the way after spending this much time studying this phenomenon, only one other manufacture approached me to discuss my findings. Jeff Quote Share this post Link to post Share on other sites
alexey 6 #36 September 25, 2006 QuoteI will post photos of them if anyone’s interested, they worked very well. Yes, please....Lexa Quote Share this post Link to post Share on other sites
bob.dino 0 #37 September 25, 2006 QuoteMaybe next time I will expand a little on where I feel the location and depth of the failure bar is set for this phenomenon. I'd love to read more on this. In-depth information posted here becomes searchable and can be read by interested folk for years to come. Quote Share this post Link to post Share on other sites
Liemberg 0 #38 September 25, 2006 Apparently you are one of the few, if not the only one, who has studied this phenomenon on a somewhat deeper level than what is usually the case in this small industry. Thanks for that. From your findings would it be safe to say - from a design point of view - that a cutter directly under the pin, below the last closing flap is "the better functional design"? (apart from looks / cosmetics) This would allow the grommets to always "start peeling from the top" whatever the loops length, tension, the pack job underneath, etcetera. Then again I could be too optimistic and this "container lock" on the remainder of the loop inside could still be possible. After all a lot of us have seen - either live or on video - main containers with spring loaded pilots remaining closed after the ripcord had been pulled and that one - as everybody knows - is usually positioned right on top of the last closing flap... I'm glad I'm not designing containers cause there's enough involved to get a permanent headache... "Whoever in discussion adduces authority uses not intellect but memory." - Leonardo da Vinci A thousand words... Quote Share this post Link to post Share on other sites
NickDG 23 #39 September 25, 2006 There are two kinds of reserve containers - Pop Tops and everything else. Everything else is just a version of the same thing - trapping the reserve pilot chute inside the container. Because the reserve ripcord pin is "exposed" on the latter, i.e. not tucked away against your back like on a Pop Top, the addition of the extra pin protection flaps, and with today's tighter reserves, cosmetic flaps, are a crutch supporting not a totally bad design, but not the best either. The problem of more flaps was addressed by adding a stronger spring to the reserve pilot chute and this can cause the possibility of the loop material being pinned between the half dozen, or so, grommets locked in place by the pressure of an aggressive pilot chute spring. Even a slight hesitation in the loop clearing the grommets can really take the starch out of your pilot chute launching. Somebody is chasing their tail here – fix one problem and create another. You don't "trap" your main's pilot chute in the container - so why do it on your reserve? You want a system that just "let's go." A reserve pilot chute should expend it's energy launching out of your burble, not pushing flap after flap after flap out of the way . . . John Sherman's Racer version of the Pop Top is essentially the same today as it was in the 1970s because it works. Later on Mick's Reflex, also a Pop Top, did make improvements. But, that was more a testament to Mick's talent than flaws in the original system. The situation nowadays is rig preference is being driven by the jumpers and not the manufactures. In the early days they gave us what they had – now they are giving us what we want – and what the hell do we know? NickD BASE 194 Quote Share this post Link to post Share on other sites
Jeffrey 0 #40 September 25, 2006 Lexa, Dave, and Peter, In my last post I really only scratched the surface on what I know about this topic. Unfortunately I don’t have a lot of time to invest into posting here. Ill try to post more of my findings on the topic as time allows. Meanwhile here are some of Pics of the tools I used and one of the tricks I used to manipulate some of the tests. I could get up to 20 cuts before having to make another blade. I got pretty good at it by the end. Nick, Did you know I use to build the SST and Racer for many years back in the mid 70’s? Jeff Quote Share this post Link to post Share on other sites
JerryBaumchen 1,048 #41 September 25, 2006 Hi Jeffrey, Can you provide any parts info on the small cutter? Also, any methods on making each part. Information is invaluable. I am sure many people would like to make their own cutter(s) and play around with activating their rig(s). I know that I want to. Jerry Quote Share this post Link to post Share on other sites
billvon 2,396 #42 September 25, 2006 >Has there ever been a case of a reserve container having the >pin pulled and due to the flaps not opening or not opening quick >enough that it caused a fatality or a problem? An early Talon had this problem. It was a small container, and the largish reserve PC barely cleared the flaps. A jumper had a hard pull and deployed the reserve. The pin cleared the loop, but the PC did not launch due to interference from the container She then went back to the main PC, struggled and finally got it out. She landed safely. This incident led to some changes in the Talon's reserve system. Quote Share this post Link to post Share on other sites
skydiverek 54 #43 September 25, 2006 Wow, that looks like some medieval items of torture ! But seriously - thanks for the research! We would love to find out more! Quote Share this post Link to post Share on other sites
dorbie 0 #44 September 25, 2006 QuoteQuote A few months ago a foreign(french?) 4 way team smoked it down and all had cypress fires. However, all of their reserves did not deploy from the Mirages they were jumping. They all realized what had happened and deployed their mains and landed safely. So yes, it has happened. Do you know if the reserves they had were too large for the containers used? It just seems incredibly odd to me that a container would have the pin pulled and not pop open due to the pressure of the springloaded PC pushing up against the flaps (non-pop top obviously). Beyond that there are obvious issues, but I'm just talking about the flaps not opening. <--one confused aggie. Maybe they were packed by the same rigger and didn't have the recent cutter mod. Enough manufacturers have upped the spring pressure over time, this distributes teh work to the flaps (IMHO). It's just not true this has never been a concern there have been rumours, incidents, test bench videos and container mods all around this issue, justified or not. Needed or not it'll put some minds at ease and is probably better than yet another more powerful pilot chute spring, it's certanly something you can market. Quote Share this post Link to post Share on other sites
sundevil777 93 #45 September 25, 2006 Even Racers have had PCs that did not launch. To say that these might have been bad rigging is not so different than the bad rigging that contributed to the cypres cutter location issue.People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am Quote Share this post Link to post Share on other sites
BigSky 2 #46 September 25, 2006 Isn't this poroblem why some of the old school rigs use to have what they called the "Jesus String"? Maybe something like that would be a good Idea today“Sometimes when I reflect back on all the beer I drink I feel ashamed. Then I look into the glass and think about the workers in the brewery and their hopes and dreams. If I didn’t drink this beer, th Quote Share this post Link to post Share on other sites
Liemberg 0 #47 September 26, 2006 QuoteMaybe they were packed by the same rigger and didn't have the recent cutter mod. Actually it is this same incident that was at the basis of the recent mirage cutter mod... You are posting in an old thread. "Whoever in discussion adduces authority uses not intellect but memory." - Leonardo da Vinci A thousand words... Quote Share this post Link to post Share on other sites
