somethinelse 0 #1 March 15, 2007 I've seen posts about canopies that'll open softly- and that they tend to be snivelly- opening slowly. Also read up about fast openings that open hard, possibly hurting you sometimes. So far I actually have experienced both types. But is it possible to have a fairly fast opening canopy that opens relatively softly?? And are there certain canopies that tend to be more gentle in their openings even tho they're fast? -LiLa. Quote Share this post Link to post Share on other sites
champu 1 #2 March 15, 2007 Being snivelly doesn't necessarily mean opening softly. Soft openings come from graceful and symmetrical inflation of the cells whether your canopy just sniveled for one second or for three. Snivelling only slows you down so much, after that you're wasting altitude. I've found rolling stuff and tucking things is a good way to make your canopy snivel longer, but controlling your slider, keeping your packjob symmetrical, making sure your lines are in trim, and staying even in your harness during deployment will make your canopy inflate symmetrically. Quote Share this post Link to post Share on other sites
Spizzzarko 0 #3 March 15, 2007 Opening shock comes from the transfering of decelleration forces to the body. If a canopy is starting to fly as it is opening then quite a bit of that shock is taken away. PD did quite a bit of testing on this and put that knowledge into their new reserve. Quote Share this post Link to post Share on other sites
somethinelse 0 #4 March 15, 2007 It's good to know there's different factors that come into play in how a canopy will open: packing carefully, canopy used and good body positioning... Thanks so much to both of you for enlightening me. I really appreciate it! LiLa. Quote Share this post Link to post Share on other sites
NWFlyer 2 #5 March 15, 2007 QuoteIt's good to know there's different factors that come into play in how a canopy will open: packing carefully, canopy used and good body positioning... Thanks so much to both of you for enlightening me. I really appreciate it! LiLa. This article has a lot of great information about how body position can affect openings."There is only one basic human right, the right to do as you damn well please. And with it comes the only basic human duty, the duty to take the consequences." -P.J. O'Rourke Quote Share this post Link to post Share on other sites
potvinj 0 #6 March 15, 2007 Yes indeed, while jumping your canopy repeatedly (at the same suspended weight and freefall speed), you will find that those slow openings will always yield softer openings than the faster openings. The reason for this is that during a slow opening, the drag generated by the partially-opened canopy is high enough to slow you down some (even during the slider-up/snivel)- so when the canopy is finally reaching its maximum surface area (during slider-descent), you are actually falling at a somewhat slower rate than during a swift opening. So your canopy will generate less drag at that moment and the opening shock will feel softer. If you go to this page http://www.pcprg.com/pifprog.htm you will find an easy-to-use computer program that tells how much force may hit you - depending on the duration of the opening. So, to not get hit by swift and hard openings, you always make sure that you dont trash-pack, have your deployment bag regularly inspected by a rigger, and maintain a good body position at deployment time. J Quote Share this post Link to post Share on other sites
diablopilot 2 #7 March 15, 2007 QuoteOpening shock comes from the transfering of decelleration forces to the body. If a canopy is starting to fly as it is opening then quite a bit of that shock is taken away. PD did quite a bit of testing on this and put that knowledge into their new reserve. So their canopies are opening closer to full flight?---------------------------------------------- You're not as good as you think you are. Seriously. Quote Share this post Link to post Share on other sites
Spizzzarko 0 #8 March 15, 2007 I wouldn't go so far as to say that. As you well know tere are many factors that determin opening shocks. Speed is a major one. Brake settings, nose design, slider size, exct exct exct. Quote Share this post Link to post Share on other sites
JohnMitchell 16 #9 March 15, 2007 I'd say perceived opening shock is a function of peak G-loading and the speed of it's onset. To slow from 120 mph to 10 mph is going to cause a G-load, the more rapid the deceleration, the higher the average G-load over that shorter time. By controlling the speed of the G-onset and then maintaining a constant G-loading until slowed should give you the softest perceived opening for any given time frame, I think. Achieving that lofty goal through engineering and packing is easier said than done. Quote Share this post Link to post Share on other sites SansSuit 1 #10 March 16, 2007 QuoteSo, to not get hit by swift and hard openings, you always make sure that you dont trash-pack, have your deployment bag regularly inspected by a rigger, and maintain a good body position at deployment time. I'm sure I know this, but for those that don't, please explain the part about how the d-bag creates a swift and/or hard openings.Peace, -Dawson. http://www.SansSuit.com The Society for the Advancement of Naked Skydiving Quote Share this post Link to post Share on other sites jakee 1,489 #11 March 16, 2007 Quote I'd say perceived opening shock is a function of peak G-loading and the speed of it's onset. I second this. I think snatch (rate of change of accelleration) is at least as important as peak g itself in determining how an opening feels. As an example, I have had a Safire2 opening that took 800ft give me more of a shock (the instant the canopy came out of the bag) than many Sabre1 openings that took 400ft that were smooth and progressive the whole way through. (Purely an example and not meant to suggest anything about Safire2 or Sabre1 openings as a whole)Do you want to have an ideagasm? Quote Share this post Link to post Share on other sites potvinj 0 #12 March 16, 2007 D-bag inspection: I was thinking about ways a mis-sized or neglected D-bag might contribute to very hard openings - for example by allowing the relative wind to start unfolding the canopy, and perhaps opening the canopy before the suspension lines are completely stretched. So I would: 1) make sure the rubber bands are always tight on the line bights - so to avoid line dumps (a concern especially with big canopies), or to avoid the canopy pushing the bag flap 1/2-opened when being extracted out of the container by the pilot chute. 2) make sure that the canopy is not "sloshing" about in an oversized bag - here I would want the folds to to unfurl only AFTER the canopy has been pulled out of the bag BY the suspension lines. In other words, I want a canopy that stays titghtly folded inside a bag that is sized just right. I would hate to have one of those off-staged openings, especially "sans" suit! ouch! J Quote Share this post Link to post Share on other sites potvinj 0 #13 March 16, 2007 Im glad you're bringing this up - in terms of the force generated, I have seen only a small number of cases where the snatch force IS the peak load. However, I agree with you that a brisk snatch, even when lower that max load, can hurt a lot since it is snatch that makes the body rotate from belly-to-Earth to toe-first. In that transition a wrong movement of the head and neck can bring pain and the feeling of hard opening. Moreover, I have read elsewhere that a very brisk snatch could also precipitate the unfolding of the canopy nose/inlets and encourage fast inflation and a harder-than-normal opening. So, yes, snatch might be as important of a factor. J Quote Share this post Link to post Share on other sites DrewEckhardt 0 #14 March 16, 2007 QuoteI've seen posts about canopies that'll open softly- and that they tend to be snivelly- opening slowly. Also read up about fast openings that open hard, possibly hurting you sometimes. So far I actually have experienced both types. But is it possible to have a fairly fast opening canopy that opens relatively softly?? Depends how you define "fairly fast" and "relatively softly." It's all relative and fairly subjective. My Monarch135 opens in less time and more firmly than a Spectre. About like a Sabre which I last jumped when that was the canopy for people who didn't want a Stiletto. I hadn't jumped it in a few years and was unpleasantly surprised. Physics just aren't going to allow a canopy to open as fast as a Monarch and as soft as a Spectre. I think it's about as hard and fast as my Fox 245 with a mesh slider or my Dagger 244 with a sail slider. PD143R and PD126R reserves open plenty quick but more progressively than those canopies. My Stiletto 120 and Samurai 105 also open in less time but more firmly than a Spectre. I can jump either all day comfortably and think that trade-off is reasonable. Brian's said that he thinks many canopies take too long to open, so I'd expect the same trade-off in the Lotus. Quote Share this post Link to post Share on other sites jbanning 0 #15 March 16, 2007 My Diablo 190 opens soft as hell, but it has also eaten up close to 1300' before, I think also the amount of jumpa a cnaopy has on it can be a slight factor also, and stowing of slider and also what you do with the nose. Quote Share this post Link to post Share on other sites JohnMitchell 16 #16 March 16, 2007 QuoteI have seen only a small number of cases where the snatch force IS the peak load. However, I agree with you that a brisk snatch, even when lower that max load, I don't think Jakee meant snatch force on the bag, but on the jumper, in other words, the rapid onset of deceleration. But yes, snatch force usually means on the bag, which can lead to line dump. And I have had high snatch forces that give you a little "smack" during deployment. Quote Share this post Link to post Share on other sites JohnMitchell 16 #17 March 16, 2007 Quote As an example, I have had a Safire2 opening that took 800ft give me more of a shock (the instant the canopy came out of the bag) than many Sabre1 openings that took 400ft that were smooth and progressive the whole way through. Yep, the old "snivel, snivel, snivel-WHACK!." Quote Share this post Link to post Share on other sites DougH 270 #18 March 16, 2007 QuoteMy Diablo 190 opens soft as hell, but it has also eaten up close to 1300' before. "The restraining order says you're only allowed to touch me in freefall" =P Quote Share this post Link to post Share on other sites ps5601 0 #19 March 16, 2007 To the OP, the short answer is YES. Many people (myself included) have had terminal velocity reserve deployments. These CAN be slammers due to a range of factors (poor body position, poor packing, poor canopy design) - however it is possible to have a fairly smooth deployment. My terminal velocity reserve deployment was "brisk" to say the least, but it was also smooth and not painful at all. In fact I have had much worse main deployments. As was mentioned above, the deciding factor is max G-force, and the angle that force is applied through your body (90 degrees to the body 'cos you are belly to Earth, or straight through 'cos you have already been stood up). Blue skies Paul Quote Share this post Link to post Share on other sites jakee 1,489 #20 March 16, 2007 QuoteI don't think Jakee meant snatch force on the bag, but on the jumper, in other words, the rapid onset of deceleration. Yes, I do apologise, I was mixing skydiving terms and physics terms What I should have written was that jolt (or jerk - rate of change of acceleration, how quickly the acceleration increases) is as important as peak acceleration itself in how most openings feel. In my experience (limited of course), that can occur either when the canopy leaves the bag, or the 'snivel snivel bang'.Do you want to have an ideagasm? Quote Share this post Link to post Share on other sites dharma1976 0 #21 March 16, 2007 yes in an open yet contained container... are you in markteting???? find what you are comfortable with as far as speed talk to your rigger and most of all be safe.... Davehttp://www.skyjunky.com CSpenceFLY - I can't believe the number of people willing to bet their life on someone else doing the right thing. Quote Share this post Link to post Share on other sites somethinelse 0 #22 March 16, 2007 thanx all. Thanx everybody...VERY interesting! Boy do I have a lot to learn. ANd No, I'm NOT in marketing, I'm just doing my own research, I guess. Expereincing a lot of other peoples packing too when I've rented rigs, YA know??? I can see that it would probably would be a really good idea to repack anything that I rent, until I got my own rig, especially so as to know what it is I'll be dealing with. B Safe, Have Fun... Blues, LiLa. Quote Share this post Link to post Share on other sites packerboy 3 #23 March 17, 2007 My limited experience with a Katana (10 jumps), all fast and pillowy soft openings. -------------------------------------------------- In matters of style, swim with the current; in matters of principle, stand like a rock. ~ Thomas Jefferson Quote Share this post Link to post Share on other sites Join the conversation You can post now and register later. If you have an account, sign in now to post with your account. Note: Your post will require moderator approval before it will be visible. Reply to this topic... × Pasted as rich text. 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SansSuit 1 #10 March 16, 2007 QuoteSo, to not get hit by swift and hard openings, you always make sure that you dont trash-pack, have your deployment bag regularly inspected by a rigger, and maintain a good body position at deployment time. I'm sure I know this, but for those that don't, please explain the part about how the d-bag creates a swift and/or hard openings.Peace, -Dawson. http://www.SansSuit.com The Society for the Advancement of Naked Skydiving Quote Share this post Link to post Share on other sites
jakee 1,489 #11 March 16, 2007 Quote I'd say perceived opening shock is a function of peak G-loading and the speed of it's onset. I second this. I think snatch (rate of change of accelleration) is at least as important as peak g itself in determining how an opening feels. As an example, I have had a Safire2 opening that took 800ft give me more of a shock (the instant the canopy came out of the bag) than many Sabre1 openings that took 400ft that were smooth and progressive the whole way through. (Purely an example and not meant to suggest anything about Safire2 or Sabre1 openings as a whole)Do you want to have an ideagasm? Quote Share this post Link to post Share on other sites
potvinj 0 #12 March 16, 2007 D-bag inspection: I was thinking about ways a mis-sized or neglected D-bag might contribute to very hard openings - for example by allowing the relative wind to start unfolding the canopy, and perhaps opening the canopy before the suspension lines are completely stretched. So I would: 1) make sure the rubber bands are always tight on the line bights - so to avoid line dumps (a concern especially with big canopies), or to avoid the canopy pushing the bag flap 1/2-opened when being extracted out of the container by the pilot chute. 2) make sure that the canopy is not "sloshing" about in an oversized bag - here I would want the folds to to unfurl only AFTER the canopy has been pulled out of the bag BY the suspension lines. In other words, I want a canopy that stays titghtly folded inside a bag that is sized just right. I would hate to have one of those off-staged openings, especially "sans" suit! ouch! J Quote Share this post Link to post Share on other sites
potvinj 0 #13 March 16, 2007 Im glad you're bringing this up - in terms of the force generated, I have seen only a small number of cases where the snatch force IS the peak load. However, I agree with you that a brisk snatch, even when lower that max load, can hurt a lot since it is snatch that makes the body rotate from belly-to-Earth to toe-first. In that transition a wrong movement of the head and neck can bring pain and the feeling of hard opening. Moreover, I have read elsewhere that a very brisk snatch could also precipitate the unfolding of the canopy nose/inlets and encourage fast inflation and a harder-than-normal opening. So, yes, snatch might be as important of a factor. J Quote Share this post Link to post Share on other sites
DrewEckhardt 0 #14 March 16, 2007 QuoteI've seen posts about canopies that'll open softly- and that they tend to be snivelly- opening slowly. Also read up about fast openings that open hard, possibly hurting you sometimes. So far I actually have experienced both types. But is it possible to have a fairly fast opening canopy that opens relatively softly?? Depends how you define "fairly fast" and "relatively softly." It's all relative and fairly subjective. My Monarch135 opens in less time and more firmly than a Spectre. About like a Sabre which I last jumped when that was the canopy for people who didn't want a Stiletto. I hadn't jumped it in a few years and was unpleasantly surprised. Physics just aren't going to allow a canopy to open as fast as a Monarch and as soft as a Spectre. I think it's about as hard and fast as my Fox 245 with a mesh slider or my Dagger 244 with a sail slider. PD143R and PD126R reserves open plenty quick but more progressively than those canopies. My Stiletto 120 and Samurai 105 also open in less time but more firmly than a Spectre. I can jump either all day comfortably and think that trade-off is reasonable. Brian's said that he thinks many canopies take too long to open, so I'd expect the same trade-off in the Lotus. Quote Share this post Link to post Share on other sites
jbanning 0 #15 March 16, 2007 My Diablo 190 opens soft as hell, but it has also eaten up close to 1300' before, I think also the amount of jumpa a cnaopy has on it can be a slight factor also, and stowing of slider and also what you do with the nose. Quote Share this post Link to post Share on other sites
JohnMitchell 16 #16 March 16, 2007 QuoteI have seen only a small number of cases where the snatch force IS the peak load. However, I agree with you that a brisk snatch, even when lower that max load, I don't think Jakee meant snatch force on the bag, but on the jumper, in other words, the rapid onset of deceleration. But yes, snatch force usually means on the bag, which can lead to line dump. And I have had high snatch forces that give you a little "smack" during deployment. Quote Share this post Link to post Share on other sites
JohnMitchell 16 #17 March 16, 2007 Quote As an example, I have had a Safire2 opening that took 800ft give me more of a shock (the instant the canopy came out of the bag) than many Sabre1 openings that took 400ft that were smooth and progressive the whole way through. Yep, the old "snivel, snivel, snivel-WHACK!." Quote Share this post Link to post Share on other sites DougH 270 #18 March 16, 2007 QuoteMy Diablo 190 opens soft as hell, but it has also eaten up close to 1300' before. "The restraining order says you're only allowed to touch me in freefall" =P Quote Share this post Link to post Share on other sites ps5601 0 #19 March 16, 2007 To the OP, the short answer is YES. Many people (myself included) have had terminal velocity reserve deployments. These CAN be slammers due to a range of factors (poor body position, poor packing, poor canopy design) - however it is possible to have a fairly smooth deployment. My terminal velocity reserve deployment was "brisk" to say the least, but it was also smooth and not painful at all. In fact I have had much worse main deployments. As was mentioned above, the deciding factor is max G-force, and the angle that force is applied through your body (90 degrees to the body 'cos you are belly to Earth, or straight through 'cos you have already been stood up). Blue skies Paul Quote Share this post Link to post Share on other sites jakee 1,489 #20 March 16, 2007 QuoteI don't think Jakee meant snatch force on the bag, but on the jumper, in other words, the rapid onset of deceleration. Yes, I do apologise, I was mixing skydiving terms and physics terms What I should have written was that jolt (or jerk - rate of change of acceleration, how quickly the acceleration increases) is as important as peak acceleration itself in how most openings feel. In my experience (limited of course), that can occur either when the canopy leaves the bag, or the 'snivel snivel bang'.Do you want to have an ideagasm? Quote Share this post Link to post Share on other sites dharma1976 0 #21 March 16, 2007 yes in an open yet contained container... are you in markteting???? find what you are comfortable with as far as speed talk to your rigger and most of all be safe.... Davehttp://www.skyjunky.com CSpenceFLY - I can't believe the number of people willing to bet their life on someone else doing the right thing. Quote Share this post Link to post Share on other sites somethinelse 0 #22 March 16, 2007 thanx all. Thanx everybody...VERY interesting! Boy do I have a lot to learn. ANd No, I'm NOT in marketing, I'm just doing my own research, I guess. Expereincing a lot of other peoples packing too when I've rented rigs, YA know??? I can see that it would probably would be a really good idea to repack anything that I rent, until I got my own rig, especially so as to know what it is I'll be dealing with. B Safe, Have Fun... Blues, LiLa. Quote Share this post Link to post Share on other sites packerboy 3 #23 March 17, 2007 My limited experience with a Katana (10 jumps), all fast and pillowy soft openings. -------------------------------------------------- In matters of style, swim with the current; in matters of principle, stand like a rock. ~ Thomas Jefferson Quote Share this post Link to post Share on other sites Join the conversation You can post now and register later. If you have an account, sign in now to post with your account. Note: Your post will require moderator approval before it will be visible. Reply to this topic... × Pasted as rich text. Paste as plain text instead Only 75 emoji are allowed. × Your link has been automatically embedded. Display as a link instead × Your previous content has been restored. Clear editor × You cannot paste images directly. Upload or insert images from URL. Insert image from URL × Desktop Tablet Phone Submit Reply 0
DougH 270 #18 March 16, 2007 QuoteMy Diablo 190 opens soft as hell, but it has also eaten up close to 1300' before. "The restraining order says you're only allowed to touch me in freefall" =P Quote Share this post Link to post Share on other sites
ps5601 0 #19 March 16, 2007 To the OP, the short answer is YES. Many people (myself included) have had terminal velocity reserve deployments. These CAN be slammers due to a range of factors (poor body position, poor packing, poor canopy design) - however it is possible to have a fairly smooth deployment. My terminal velocity reserve deployment was "brisk" to say the least, but it was also smooth and not painful at all. In fact I have had much worse main deployments. As was mentioned above, the deciding factor is max G-force, and the angle that force is applied through your body (90 degrees to the body 'cos you are belly to Earth, or straight through 'cos you have already been stood up). Blue skies Paul Quote Share this post Link to post Share on other sites
jakee 1,489 #20 March 16, 2007 QuoteI don't think Jakee meant snatch force on the bag, but on the jumper, in other words, the rapid onset of deceleration. Yes, I do apologise, I was mixing skydiving terms and physics terms What I should have written was that jolt (or jerk - rate of change of acceleration, how quickly the acceleration increases) is as important as peak acceleration itself in how most openings feel. In my experience (limited of course), that can occur either when the canopy leaves the bag, or the 'snivel snivel bang'.Do you want to have an ideagasm? Quote Share this post Link to post Share on other sites
dharma1976 0 #21 March 16, 2007 yes in an open yet contained container... are you in markteting???? find what you are comfortable with as far as speed talk to your rigger and most of all be safe.... Davehttp://www.skyjunky.com CSpenceFLY - I can't believe the number of people willing to bet their life on someone else doing the right thing. Quote Share this post Link to post Share on other sites
somethinelse 0 #22 March 16, 2007 thanx all. Thanx everybody...VERY interesting! Boy do I have a lot to learn. ANd No, I'm NOT in marketing, I'm just doing my own research, I guess. Expereincing a lot of other peoples packing too when I've rented rigs, YA know??? I can see that it would probably would be a really good idea to repack anything that I rent, until I got my own rig, especially so as to know what it is I'll be dealing with. B Safe, Have Fun... Blues, LiLa. Quote Share this post Link to post Share on other sites
packerboy 3 #23 March 17, 2007 My limited experience with a Katana (10 jumps), all fast and pillowy soft openings. -------------------------------------------------- In matters of style, swim with the current; in matters of principle, stand like a rock. ~ Thomas Jefferson Quote Share this post Link to post Share on other sites
