alan

Yes Paul, I agree, what was discussed was a matter of degrees....including turbulence, both light and the canopy collapsing variety. Problem is, you don't always know or realize you are in the latter until it happens. Also, I was trying to focus the dicussion on landing approaches and they are a matter of degrees also....are you on downwind, final, or a carving approach, what kind of canpy (one of the newer HP variety was my focus), the altitude in the approach, etc.. I've never disagreed with the notion that all canopies can collapse. As far as using brakes to put the canopy back into a configuration for re-inflation after collapse, again, I would prefer to avoid the collapse in the first place even though I realize that that is not always possible. But I do know that brakes will put the canopy closer to collapse, especially in heavy turbulence. Re-inflation is, as you put it, a matter of degrees also. At 50 feet, on final, on let's say a Cobalt as one example out of many, I doubt brakes would be of much use for re-inflation. Sure, you would likely hit the ground with less energy, but why assume the worst ( turbulence that will collapse the canopy) instead of using speed to avoid the collapse? And at 50', perhaps dead is dead, no matter how fast you are going when you die. It is a matter of degrees, judgement, and experience. Please note that that was my point all along.....Do not just take the old advice of brakes on todays newer canopies and not question or test it. BTW, I have noticed in a later post in this thread by Michelle, that the Evolution School of Canopy Flight apparently shares my opinion and I believe Jim S. is a pretty credible authority, at least as credible as bill von, so I would still urge people to not just acccept the advice of using brakes when flying in turbulence during a landing approach. alan

No one made any assumptions. It was pointed out that the FARs specify who can make alterations to a main and that a Master Rigger is included in those who can. It was informational in nature since the original post was unclear. I have run across a surprising number of jumpers and riggers that are unclear on the rules as to who can alter a main canopy. A follow up post clearly said "if" the rigger was performing illegal mods it was an issue. alan

I don't mean to pick on you, but it seems as if the course may not be such a great value. It appears not to have covered or if it did, left much of an impression on you, what probably contributes to more skydiving related injuries than any one other factor. I'm sure the personal insights that are added are valuable, especially when you say with a certain amount of pride that you have been personally coached by one of the best. But, no certain recollection of this being covered?????? What a shame. I do have to say that I agree with your non-instructor point of view, but bill von certainly makes an arguement that brakes will minimize the injury because of the slower speed at impact. My view is that it minimizes injuries that become more probably because of the brakes. He and someone else even came up with some quotes about flying paragliders in turbulence, although none of them seemed to address the issue of landing, just what do do at altitude, presumeably in the extreme turbulence encountered in mountain flying. I hope no one was taking much of that stuff too seriously, but rather went out and got some advice at the DZ and under supervision, experimented progressively to find out how their canopies fly in real life. alan

No, I don't think anyone has been saying that 1000' openings are not possible, just rare, especially on canopies that have not been modified or specifally designed to open longer. Your comments seem to confirm that. For quite some time now, I have been attempting to get people here to realize that todays slow opening canopies open in about 600' to 800'. You also seem to be confirming that, with yours' on the longer end of the spectrum. Some open in 400' to 600' and still provide very soft, comfortable openings. Then we get into those who have 1000' "snivels"......consistently no less. They must all be jumping canopies that were designed to take longer than desired to open. Any way, I asked if you had video showing a standard Cobalt consistently taking 1000' to open. I guess that would be a "no" for now. Hey while I have you, what are your thoughts on using 1/4 to 1/2 brakes while landing in turbulence under a Cobalt? What kind of factor would wing loading play in the 1.2 to 2.2 range? Maybe you could start a thread in the canopy forum with your reply. alan

I'm curious, what did they have to say about landing in turbulence under modern canopies. Do they advocate using 1/4 or 1/2 brakes on final or full flight? Seems like an important topic, I would hope they covered it. alan

You might want to check the trim specs on your outboard "A" lines. It is possible they have shrunk or are simply just out of trim. They could also be the cause of the bucking and may even contribute to a partial collapse under the right circumstances. Just a thought to toss in with the other answers. alan

Dan, I think anyone who has been around for a while will agree that the new breed of tandem canopies takes longer to open (although I have video of several opening in 2 sec flat....main, not reserve), but the focus of the threads on this topic has usually been on sport canopies. You are talking about a special use canopy designed to take longer. Do you have any links with a standard Cobalt showing them to "consistently" take a thousand feet or more to open? And let's not forget, some of these claims are for 1000' "snivels", not the whole opening. alan

Yes, I agree, no harm...no foul. I wonder if the rigger understood the risk he was taking. I wasn't trying to be too serious and I'm not very good at clicking on all the goofy faces, but this forum is for the exchange of information and I thought it was important to point this detail out. You'd be surprised at how many riggers are out there that would not even realize they are risking their ticket and perhaps a lawsuit by doing this. When I was a kid palying with BB guns, my mom would say, "Yes, it's all fun and games until somebody looses an eye." I wonder what she was trying to teach me. alan

Yes, Scuba shops should have suitable silicone, maybe a little pricey though. When at ACE, just check out the labels on the variety of sprays available, some will be food grade and others won't. If they are it will say so on the label. Food grade just means it can be used as a lubricant on machinery, belts, etc. in a food processing environment and by no means is intended for direct consumption. Even the food grade cans have the "DANGER! EXTREMELY FLAMMABLE", and "HARMFUL OR FATAL IF SWALLOWED" warnings on them. alan

You do realize that you are travelling vertically at about 176'/sec when you break off as planned at 3500'? Better do some simple math and you will realize how unlikely it is for you to track "flat but long" or get out of Dodge religiously and still open at 3000' Turn, track, check air, wave off, and deploy all in less than 3 seconds??? That being said, it sounds as if the unlicensed jumper made a serious error and you handled it well. Does the other person have a "Coach" or Instructor? Maybe a gentle and discreet mention of it to them would be helpful to someone else down the road. alan

Most of us skeptics aren't referencing a canopy that has been modified to such an extent, just a stock version of any of the popular canopies in use today. 1000' openings are a rare exception for sport canopies and yours would fall into that category, especially since you admit it was a smacker and then you had it modified. As Phree has pointed out, get video and time it. Has anyone else noticed that every time this has come up here, not one manufacturer has posted anything to support the 1000' opening claims? Not even the ones that like to promote the soft opening canopies they sell? Dan Preston from Atair claims his canopies open soft and are freefly safe. He posts here often with technical data. Nothing from him on the subject, and judging from the posts here by Cobalt owners, they do open soft as a general rule. I talked to John LeBlanc about it once quite awhile ago and I think I even posted a cut and paste of parts of an e-mail he sent me. He basically said most claims of 1000' openings are exaggerated and on the rare occasions that they do get a canopy back because it opens slow and his test jumpers confirm it, their comment is usually something like "what are they complaining about and do they want to sell it?" BTW, unless your local rigger met some very specific requirements under the FARs, his modification to your main canopy was illegal. Anyone can make a main and jump it, but only a master rigger or the manufacturer can peform an alteration. That is probably why that rule is in place. alan

I wrote a rather extensive evaluation of it last year. I think you may still be able to find it on this site somewhere. Great canopy and great openings. alan

Kill-line wear is a problem, I have had to replace several for customers that have broken. They also tend to shrink from heat generated by the friction from the collapse on opening. I apply a food grade silicone to mine to reduce wear and friction that will shrink it. A pc with a too short kill-line may not function properly. There have been several good threads about pc's here lately (although not addressing your question specifically), do a search. Bill Booth made a very detailed post about proper pc design. The split ring works very well and in fact, Rigging Innovations supplies them with their new rigs.....the latest Talons and Voodoos that I have assembled came with the split ring instead of the rapide link. The ring does not cause wear on the line, the two loops, or the grommet. I'd never use the rapide link again. alan

ACE Hardware has it. usually near the automotive dept. alan

I've been using soft links now for over 3 years and close to a 1000 jumps I would guess. Never had to chase a pc yet and they are showing no appreciable wear. They are easier/quicker to use and change pc's than screwing around with a larkshead on a bridle that doesn't already have the loop for it. I wouldn't use one on a canopy that has a webbing-ring-webbing bridle attachment ( I think PD canopies use this ) because of the fabric to fabric wear. They work well when attaching fabric (webbing) to metal though. alan

If you use fresh mil spec rubber bands and spray them with food grade silicone they will last as long or longer than tube stowes and hold your lines properly. My rubber bands often last 200 to 300 jumps. I even use the small bands on the HMA lines which are much thinner than microline and they still hold fine without double stowing. The silicone spray is also ideal (and recommended by several manufacturers) for cleaning and lubricating your cutaway cables at least once a month. Want to make your closing loops last longer? Make them out of Spectra and spary them with the silicone. One word of caution though, Spectra is very easily damaged by the friction heat from zipping a pull-up cord out, even once, and it is hidden against the pin. Don't use it if you use a packer that you can't trust to slowly remove the pull-up cord. alan

Phree, get a copy of a Rigging Innovations Owner's Manual, it contains a very thorough checklist for the assembly and inspection of a harness container system with a main and reserve canopy. alan

We're talking about flying in brakes during turbulent conditions near the ground. A flat turn in turbulence near the ground implies you are in brakes, maybe not 1/4 or 1/2. but maybe you are. Then it would be bad. BTW, I can land my VX nicely in 1/4 brakes. 1/2 brakes, well maybe there are better pilots than me out there, any of you care to comment? I've tried the 1/4 brake thing you advocate in mild to strong turbulence. you can come up with as many theories as you want to. Actual life real practice has demonstrate dto me that you have great arguements but they don't work in the real world. I've jumped a wide variety of the new higher performance canopies in bith calm and turbulent conditions. I can land any of them nicely in 1/4 brakes on a calm day. When I attempt to do it in turbulence, the canopy becomes very difficult to control and I often(usually) have a less than glamorous landing with a canopy that is stalled or very near it. Increased AOA, when it exceeds the critical angle, willcause the canopy to stall. If the AOA is not immediately reduced (let up a little on the toggles), the canopy will collapse or fortune cooky. That is the problem, the stall occurs before the collapse, except possible in extreme cases of violently turbulent conditions. In that case, neither brakes nor full air speed will be of much help. See my comments above. In my experience, rarely does turbulence alone cause a collapse. A collapse is usually after a stall has occured while someone was flying in 1/2 brakes during turbulence. My experience has mostly been in the last 10 to 12 years. Yours goes back much further to older canopy designs. Maybe that has had some carry over effect. Neither do I, but then I don't dismiss as much as you do either. It is an important factor and your arguements seem to dismiss it on the basis of extreme cases of turbulence, not the kind we ordinarily find ourselves jumping in and when we see the crash and burns. Here is where we have to agree to disagree. I do note that you have gone from 1/4 or 1/2 brakes to "some small amount." You know Bill, after I plane out and am surfing, I always have "some small amount" of brakes in (well, except for rear riser landings, but those I finish with brakes). It is normal on every canopy I jump, from a Manta 288 to a VX 89. I just don't like to use the brakes on the approach....as in before the rovery arc. Maybe semantics has been our problem. Again, that is a really rare case....like a dust devil. We just don't usually jump in conditions that are that turbulent. I would argue that if it is that turbulent that it will collapse a full flight canopy, then it will do the same to one in brakes, perhaps not in the same manner but the end result is the same. I've hit strong mechanical turbulence (rotors from buildings and trees in 20 mph winds) at full flight (60+mph) and felt some sudden bumps but no collapse. The only brakes I use are a bump in the recovery arc to plane out and then the normal smooth application to surf and flare. Not much surf BTW. So bill, just how fast are we talking about here and what kind of turbulence? Agreed. Actually, for the stall to have ocurred, you would already be in brakes and usually pretty deep brakes. What you do is let up a little to let the canopy recover and build up speed with minimal surge. Exactly my point all along. Riding in brakes 30 feet up in turbulance is a very good way to find yourself in a stall that you won't be able to recover from. Adding brakes in a stall is absurd and I doubt you teach that in your FJC. As the canopy rocks back just prior to a stall, you can prevent the stall by letting up a few inches. Once the canopy stalls, don't let the brakes all the way up, just ease aup a few inches and hold them there until the canopy recovers, then smoothly return to full flight. Does any of that sound familiar? The old C172 stalls, the drops over as the wing tries to build speed and recover. The pilot pulls back on the yoke. It won't recover. I wonder what flight manual recommends adding flaps in a stall. Oh yeah, those old rigid airfoils are different. Funny, Quade says a wing is a wing and the aerodynamic principals are the same. Maybe he is wrong. I could go back in the archives and dig up a post by you where you argued the opposite, that our canopies can't go fast enough to experience "structural failure". I guess you define that however it is most beneficial to your current arguement. Yeah, agree to disagree. My advice is anyone reading this has seen good arguements both ways. Go out on your canopy in see for yourselves. Start in calm conditions and try landing in 1/4 or 1/2 brakes and no brakes, then work progressively into more turbulent conditions until it makes you uncomfortable. Then quit. You have found your limit and what works best for your on that canopy. As you get more experience you may find that your comfort level has expanded and you have a bigger envelope. The real trick is knowing when to quit, when you are out of the envelope. Many of us find this several times over the years and it is usually punctuated with a cast (or worse) for 6 or 8 weeks. Neat story, except we are not standing in a wind, we are flying in it and are not a fixed object, we are part over that ocean of air that the turbulence occurs in. We are also not exposing ourselves to those extremes and the house is not an aerodynamic structure. OK, if you say so, I don't agree though. My grandmother fell and broke her hip. At 94 that is pretty serious so I'm off to NJ to tend to her. Hate to break off the debate, but I'll be gone for awhile. Time to end it anyway. I wonder why Quade, Chuck, Hook and few others didn't offer an opinion, they certainly have a knowledge of the aerodynamics combined with practical experience. alan

Odd, a less efficient airfoil would stall at a higher airspeed with less AOA. Turbulence will more easily cause that threshold to be crossed on an airfoil flying closer to it, ie. a canopy in brakes or a C172 in flaps at a reduced airspeed. Additionally, the discussion was not about the realtive violence of the stall, but the the occurance of the stall. I don't know what you mean by holding as much energy in your body as possible before landing. I meant to not dissipate it in turbulence during the landing approach by prematurely using the brakes to buffer out the effects of the turbulence. I meant to use the mass of the canopy combined with the jumper and the speed of that mass to counter effect the energy imposed on the system by turbulence. Once the turbulence has been dealt with, then dissipate that energy as we normally would with the flare technique that works best for the particular jumper/canopy. That has kinda been my point all along. I don't think that the majority of the newer canopies at the wing loadings that seem to be popular with todays pilots can be safely flared in 1/4 or 1/2 brakes in turbulent conditions. Hell, for that matter, most of the pilots I see can't land well in good conditions in 1/2 brakes. Definitely slows you. I think it makes you greatly more susceptable to turbulence, but not just because of reduced internal pressure of the canopy. An increased AOA and external pressure changes can effect a stall and/or a collapse. Applying brakes squeezes air out and allows relatively smaller forces outside the canopy to exaggerate the effect. It's not just about how fast you are going. It is a combination of the design parameters of the particular canopy, AOA, internal pressure and external pressure (turbulence). Going slow buffers the perception of the turbulence and is a factor that by itself can reduce the effects, but the whole picture results in a greater probability of an impact with the ground. You might also consider that at a higher speed, one might feel a sharper, more abrupt bump from the turbulence, but you pass through it before it moves you very far. In other words, by going slower you allow it to act on you longer and move you farther. Again, it makes the collapse or stall more likely to happen in the first place. I would rather avoid the injury all together than minimize an unnecessary one. And don't confuse a stall with a collapse. Yes, being in brakes may help a collapsed canopy reinflate more quickly, but it won't necessarily help it recver from a stall, it may actually inhibit stall recovery as in a secondary stall. Again, old advice from the old days, with big old canopies that in brakes acted more like a "parachute" than a non-rigid ramair wing. We're not talking about structural failure here. We're talking about turbulence near the ground causing a wing to abruptly stop flying or change altitude. A wing stalling or collapsing is a symptom of the effects of turbulence. Skydivers as a general rule don't jump in conditions that would cause a Cessna's wing to fold. And, if fewer canopy pilots followed the advice to fly in brakes on landing approach in turbulence, you would see fewer crashing with their wings collapsed. If you go faster,t he changes happen faster and you are exposed to the forces for less time, so they will move you less but more abruptly. The turbulence is the same. You don't create more or less of it, you can control how much you let it affect you. alan

Really? How so? Are you implying that a C172 pilot with his engine out would land with flaps down and a reduced airspeed in turbulence as compared to what he would do in calm conditions? Engine or no, that pilot is not going to add flaps and reduce his airspeed when landing in turbulence. Franck, I think we are on the same page. That is pretty much a summary of what I said in the original post about brakes being bad advice on todays newer canopy designs and expanded on in my subsequent posts. alan

Yes, or Talk Back or Gear reviews, depending on which part of the thread you are reading. I never felt it belonged here in the first place. But here it started and that is where I had to reply with my opinions. alan

They kinda go hand in hand. Increase the angle of attack too much or decrease it too much and the stagnation point moves above or below the nose inlet. Either way, it has a venturi effect and will depressurize the canopy. Any wing that exceeds its' critical angle of attack will stall and a stall should not be confused with a collapse. Yes and inducing a secondary stall by stabbing the brakes in a panicked attempt to recover from a stall caused by turbulence can cause you to impact with less energy than just letting the stalled canopy surge and recover. But, a smooth controlled application after the surge may allow the canopy to recover before impact and therby no injury results. None is better than reduced. We have to bear in mind that some situatiuons are simply not recoverable. So yes, letting the canopy surge and applying smooth, aggressive brakes won't always save you and you may hit the ground with more energy than if you go to full brakes and just "parachute" it in. But, letting the canopy fly or even using a little careful front riser may let you avoid the entire situation. I would generally choose prevention over cure or treatment. I believe that on most modern canopies, increasing the angle of attack does not take it farther away from the angle at which it stops flying, but actually moves it closer and makes it more susceptable to turbulence induced stalls. I think this is the point at which we fundamentally are not in agreement. Sounds like good advice and leads me to believe you are approaching this more from an at altitude point of view rather than on landing approach. You can also "see" your gide ratio improve as well as feel it. I use the old "accuracy trick". Find the point in front of you that doesn't appear to move as you approach it, then as you apply brakes it appears to sink as you approach it. You are improving your glide ratio as long as that happens. As soon as it appears to sink, you have gone into too much brake and the glide starts to drop off. Agreed and as a side point, I have never flown a paraglider, just a wide variety of canopies. alan

Yes, good point. I do come in (surf) a little higher as well and yes we are talking primarily about x-braced canopies although I don't exclude canopies such as the Crossfire, Stiletto, Vengeance and such. alan

Yes, in my opinion it is. But you know that it has a very long recovery arc to begin with, so it is still very long compared to other canopies. alan

Reduced pressurization results in amore distorted and much less efficient canopy. One that is much more prone to significant reaction to turbulence. Up high, no big deal, close to the ground and you might eat some of it. It also puts the canopy in a better position to collapse in the first place. So again, altitude should affect the decision here. That is true and all very nice but it also increases the likelyhood of impact with the ground. So, we can choose to reduce our energy and minimize injuries or we can choose to conserve energy and avoid the injury in the first place. Agreed. But, I think the chances of the two foot dip are higher under the Tri. in brakes than the canopy at 2:1 in full flight. BTW, what would be the assumed wing loading of the Tri? 1:1, 1.2:1, 1.4:1? It does matter. Another way to look at it is any time you are moving slower, you have less energy to transfer into injury. But, and this is a big but, I still maintain that with the majority of todays newer designs, you are increasing the likelyhood of turbulkence dropping you into the ground by flying in brakes on landing approach. A light aircraft pilot, say a C152 or C172, does not add flaps and reduce airspeed when making a landing approach. The common practice is to add airspeed (1/2 the gust) and use no flaps. Why is that so hard to understand and apply to todays canopies. Of course we could argue that if we reduced airspeed and used flaps, the crash would be less severe. Most pilots choose to follow the flight manual and avoid the crash all together. Absolutely agreed. True, but I'll add that flying at full speed will keep it inflated in turbulence that would collapse it at slower speeds in brakes. flying in 1/4 to 1/2 brakes may help you survive a bad incidence of turbulence. *** I think it will reduce the amount of energy with which you might impact the ground, but I also think you are more likely to impact the gound. alan