Hooknswoop 19 #26 February 28, 2003 QuoteSo the cypres fires at about 350 - 400 feet after a cutaway at 700. don't give much time for an opening / picking a spot to land. And the Cypres firing at 750 feet at terminal doesn't give you much time either. It wasn't designed too. If you fall 366 ft in 5 seconds to get to Cypres firing speed after a cutaway at 800 feet, that leaves 434 feet for deployment, not much room in either case, but should be enough to get a completely deployed reserve out before impact. Saddling in under a reserve at less than 300 feet, a jumper shouldn't care that they don't have much altitude left to find a landing area, etc, they should just be happy to be alive. If you don't have the altitude to get stable after cutting away, you have already made some mistakes, 1) Pulled too low, or 2) Stayed with a malfunctioning canopy too long, or are unable to find or pull the reserve ripcord immediately. If you are low with a malfunction, an immediate reserve pull (manually [best] or by the RSL [if installed, second best] is extremely important. Best advice is to avoid this situation. Where and RSL helps down low, if you make a mistake and get there, or are unable to activate the reserve manually, it hurts up high. Stability makes for a better opening, that is a fact. An RSL can take away the option of being stable for reserve deployment. There have been fatalities where an RSL (or action on the part of the jumper) would have prevented a fatality. There have also been fatalities where the RSL contributed to the fatality (broken riser resulting in a main/reserve entanglement, RSL activated reserve on main deployment resulting in a main/reserve entanglement). There has been more "saves", by far, by RSL's than fatalities by RSL's, but again, RSL's are not perfect. The RSL debate cannot be solved, by statistics or opinions. Each jumper must educate themselves about RSL's and their function and limitations and decide for themselves to jump with one or not. The SIM's (now available on line at the USPA web page, www.USPA.org), lists the disadvantages associated with RSL's. The type of gear, the type of and the type of jumps must be considered when deciding to use an RSL. If installed, effort must be made to not rely on it to activate the reserve for the jumper. This effort starts long before a malfunction, with Emergency Procedures training. Also, an RSL can be disconnected for some jumps and re-connected for others ver easily. Make sure that a disconnected RSL is secured and will not interfere with the operation of the 3-ring release or any other part of your gear, to include flapping freely in free-fall. The Skyhook from RWS seems to have solved most of the shortcomings of the RSL Hook Quote Share this post Link to post Share on other sites
kallend 2,027 #27 February 28, 2003 Quote Quote According to an old and possibly inaccurate freefall table I have: After 5 seconds your speed will be 124 feet/second. After 5 seconds you will have fallen 366 feet. Yeah that seems pretty accurate actually. Just remembered someone telling me once that a skydiver accelerates at 18 ft/s/s . I guess that person wasn't a physicist or an engineer.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
Hooknswoop 19 #28 February 28, 2003 QuoteAccording to an old and possibly inaccurate freefall table I have: After 5 seconds your speed will be 124 feet/second. After 5 seconds you will have fallen 366 feet. -------------------------------------------------------------------------------- Yeah that seems pretty accurate actually. Just remembered someone telling me once that a skydiver accelerates at 18 ft/s/s so that seems bout right.. the first 5 seconds is around 500 feet? So on that basis you'd have to be cutaway by 1200 ft for the cypres to take effect. No a cutaway at 700 feet puts you above the firing speed of the Cypres by 434 feet, which should be enough for a reserve opening. It doesn't disarm until 130 feet. No guarantees, but cutting away at 700 feet and doing nothing, there shouldn't be any guarantees. Hook Quote Share this post Link to post Share on other sites
nacmacfeegle 0 #29 February 28, 2003 Hook... "If you don't have the altitude to get stable after cutting away, you have already made some mistakes," one possible exception, is if somebody "swoops" into your canopy, thereby trashing it.....I've seen this happen in Spain and it aint purteee.... Good reason for an RSL, she wasn't wearing one, but still got the nylon above her head.-------------------- He who receives an idea from me, receives instruction himself without lessening mine; as he who lights his taper at mine, receives light without darkening me. Thomas Jefferson Quote Share this post Link to post Share on other sites
Hooknswoop 19 #30 February 28, 2003 Quoteone possible exception, is if somebody "swoops" into your canopy, thereby trashing it.....I've seen this happen in Spain and it aint purteee.... Good reason for an RSL, she wasn't wearing one, but still got the nylon above her head. There are exceptions to everything. Crew Jumpers generally don't use RSL's and they probably have the highest jump/cutaway rate. If in a collision/wrap situation, and there is enough altitude, falling free of the mess is your best option and having to remember to disconnect the RSL, then find the little red (yellow) tab, in a wrap, disconnect it, then cutaway and pull the reserve is a lot to ask. If there isn't enough altitude, firing the reserve to get more fabric over your head is the way to go. In both of these situations, an RSL doesn't help and in the first, makes it worse. If the collision damages your main, rendering it unsafe to land but does not result in a wrap with the other jumper, either a cutaway followed by a fast reserve pull (the RSL can be of help here) or pulling the reserve to add more fabric if too low for a cutaway (RSL is no factor here) is the way to go. So of the 4 collision scenarios: Wrap High Wrap Low No-Wrap High No-Wrap Low Only in the No-Wrap Low scenario is the RSL really helpful and only if the jumper doesn't or is unable to activate the reserve manually in a timely manner. In the No-Wrap High, the RSL may be of help if, again, the jumper doesn't or is unable to manually activate the reserve. In Wrap High or Wrap Low it is either a disadvantage or moot, respectfully. One size doesn't fit all and it depends on the situation if the RSL is a help or hindrance. You have to decide what is most likely for you. Hook Quote Share this post Link to post Share on other sites
nacmacfeegle 0 #31 February 28, 2003 "One size doesn't fit all and it depends on the situation if the RSL is a help or hindrance. You have to decide what is most likely for you." Definitely on the same page as you... -------------------- He who receives an idea from me, receives instruction himself without lessening mine; as he who lights his taper at mine, receives light without darkening me. Thomas Jefferson Quote Share this post Link to post Share on other sites
billvon 2,995 #32 February 28, 2003 >On a side note does anyone know the height, approximately, >someone would have to fall to get to cypress activation speed? I ran the numbers a while back, and if you cut away from a main at 600 feet, you'd get a cypres firing at approx 200 feet. Your reserve likely would not open in time but you would at least begin to slow down before impact. Quote Share this post Link to post Share on other sites
billvon 2,995 #33 February 28, 2003 >Just remembered someone telling me once that a skydiver > accelerates at 18 ft/s/s so that seems bout right.. 32 fps^2 initially, decreasing to zero as they approach terminal. For the first 3-4 seconds you can essentially neglect drag. Quote Share this post Link to post Share on other sites
Rdutch 0 #34 February 28, 2003 ***Absolutely, but I bet it'll be a pain to get it cross-certified for anything but RWS rigs. Actually the skyhook will be easy to put on other rig's, its all a licensing issue, The skyhook doesn't modify the deployment system, thus the no need for a new tso on it. The original design required the bridle to be cut to install it, this violated the tso, the new one doesn't change the original reserve system the bridle stays intact. Someone mentioned that if you spin a weight on a rope and let go it fly's away, true, but if you cut away from a spinning main it wont stop you from doing a back/front flip as your reserve is deploying, this can cause a tangle, or a flip through your risers while deploying. The skyhook theory is to deploy your reserve before you can flip, from the pictures Ive seen so far it seem's to work great. Go to www.relativeworkshop.com I also whitnessed a test jumper with his canopy hooked up backwards do a skyhook cutaway, while spinning, to simulate an on your back deployment and that went fine also. That said even after whitnessing it first hand, as a videographer, I still think I will wait a while until I use it. Ray Small and fast what every girl dreams of! Quote Share this post Link to post Share on other sites
JayhawkJumper 0 #35 February 28, 2003 If you just got a new rig and are asking about the RSL you probably don't have a canopy that would spin up, but then again you might. you never know. Just find an instructor you trust, have a conversation with them and figure out what will work best for you. Quote Share this post Link to post Share on other sites
rigging65 0 #36 February 28, 2003 QuoteActually the skyhook will be easy to put on other rig's, its all a licensing issue, The skyhook doesn't modify the deployment system, thus the no need for a new tso on it. The original design required the bridle to be cut to install it, this violated the tso, the new one doesn't change the original reserve system the bridle stays intact. I don't think this is correct at all. You're introducing a system that interacts with a TSO'd piece of gear (the reserve deployment system). It also interacts with the RSL. By simply sewing the Hook onto the reserve bridle, you've created an alteration/modification to a TSO'd item. This requires approval to do. Both the Reserve Deployment system and the RSL must have drawings and MOS sheets onfile with the FAA. If you change anything to these items, you have to refile paperwork and get the changes approved. Now, you might be able to write these changes through as "Industry Standard" if you're MIDO is cool with you, but I can pretty much guarantee you ours wouldn't let it go at that. Having dealt with the FAA on these issues for the last year+, I can tell you this. If you change much of anything to the TSO'd portions of your rig, they're gonna want to see something proving it improves the design, or they're going to make you retest. If the Skyhook turns out to be as cool as I think it's going to, MFgs. might decide to go to the lengths to include it on their rigs, but it's not going to be as simple as just "adding it". "...and once you had tasted flight, you will walk the earth with your eyes turned skyward. For there you have been, and there you long to return..." Quote Share this post Link to post Share on other sites
Rdutch 0 #37 February 28, 2003 I talked to BillBooth about it, at the PIA and he told me that the early design of the skyhook would need a new tso, because they made the bridle 2 pieces, but since the bridle is all one piece now and the way the bridle is attatched to the skyhook, it falls under the tso that the vector reserve deployment system uses. That is why there are rigs being fitted with skyhooks right now. I've only heard of student rigs being outfitted so far, I think it has something to do with how big a student canopy is. If you have any questions Im sure Bill will answer them. But that is what I understood when I talked to him about it. Ray Small and fast what every girl dreams of! Quote Share this post Link to post Share on other sites
rigging65 0 #38 February 28, 2003 QuoteI talked to BillBooth about it, at the PIA and he told me that the early design of the skyhook would need a new tso, because they made the bridle 2 pieces, but since the bridle is all one piece now and the way the bridle is attatched to the skyhook, it falls under the tso that the vector reserve deployment system uses. That is why there are rigs being fitted with skyhooks right now. I've only heard of student rigs being outfitted so far, I think it has something to do with how big a student canopy is. If you have any questions Im sure Bill will answer them. But that is what I understood when I talked to him about it. Yes, they can be fitted to RWS rigs, but right now that's it. Any other Mfg. would require paperwork changes and modifications to their TSO (of some sort) to allow it on their rigs. That was kind of my whole point...it's not going to be real easy to get it on just any rig you want to jump, at least not right away... "...and once you had tasted flight, you will walk the earth with your eyes turned skyward. For there you have been, and there you long to return..." Quote Share this post Link to post Share on other sites
murrays 0 #39 February 28, 2003 The only situation, other than crw, that I can think of where an RSL or the Skyhook may not be advisable is camera jumping. Making sure your helmet is clear before opening your reserve is something that I think advisable. As mentioned in a previous thread on the skyhook, there have been instances where camerajumpers have cutaway from spun up canopies in situations where they couldn't tell if they had a snag or not. This would be my only reservation.If it is possible to disconnect the rsl/skyhook when jumping camera, that would be an ideal situation. I think the Skyhook is a great invention...but it will take time and real world experiences to reveal any unforeseen issues.-- Murray "No tyranny is so irksome as petty tyranny: the officious demands of policemen, government clerks, and electromechanical gadgets." - Edward Abbey Quote Share this post Link to post Share on other sites
Slink2 0 #40 March 1, 2003 I have an RSL and began wondering the same thing. I like how those that live here tell you to do a search. As if everyone that WAS here left ALL the input you will ever need to know about that subject! New members will never get to comment on the RSL.I still don't know weather to keep it or get rid of it. But I do know that I have read about more fatalities where one would have helped rather than have been a problem. Quote Share this post Link to post Share on other sites
mikeat10500 12 #41 March 1, 2003 Hi Slink Keep your RSL and keep it functional unless you are doing CRW. Very experienced people have cutaway low or only cut away and would have been saved by an RSL. Do not be concerned about being stable when the RSL activates the reserve. When you cut away it's not that you are unstable, your just not face to earth...and that's ok. mike QuoteI have an RSL and began wondering the same thing. I like how those that live here tell you to do a search. As if everyone that WAS here left ALL the input you will ever need to know about that subject! New members will never get to comment on the RSL.I still don't know weather to keep it or get rid of it. But I do know that I have read about more fatalities where one would have helped rather than have been a problem.----------------------------------- Mike Wheadon B-3715,HEMP#1 Higher Expectations for Modern Parachutists. Quote Share this post Link to post Share on other sites
