DBCOOPER 1 #26 December 22, 2003 Was the smaller pilot chute a fix, or was it always recommended for the Cobalts?Replying to: Re: Stall On Jump Run Emergency Procedure? by billvon If the plane is unrecoverable then exiting is a very very good idea. Quote Share this post Link to post Share on other sites
cloud9 0 #27 December 23, 2003 From the PD web site: 3. PILOT CHUTE The pilot chute has a big effect on canopy deployments. The size, type of fabric, length of bridle, apex length, mesh size, and aerodynamic shape all affect the deployment of the parachute. Some pilot chutes have too much drag at terminal velocity. This can cause these problems: 1. They slow the bagged canopy down so quickly that the chance of line dump is increased. 2. When reaching line stretch, the jumper instantly accelerates the canopy back to his speed, since it is attached to him by the fully deployed lines. This is the first force the jumper feels at line stretch. (Moments later, the canopy starts to fill with air and slows down again.) A pilot chute with too much drag will have slowed the bagged canopy down so much that the jumper will experience quite a strong force when the canopy reaches line stretch. The canopy feels this jolt too, and the pack job will be forcefully spread apart by this force. This can cause harder openings, since the now disorganized canopy will inflate more quickly. In extreme cases, it may even open hard enough to cause structural damage to the parachute system. A pilot chute with more moderate drag will get the canopy to line stretch with less severe shock to the jumper and the canopy. The line dump problem is also less likely to occur, and the pack job is more likely to be released from the bag in an orderly fashion. Although a pilot chute with more moderate drag will produce more consistent openings, a pilot chute can have too little drag. This could happen if it is too worn out, too small, malfunctioned, or designed improperly. The danger here is obvious. The pilot chute must consistently function correctly. If it does not, a bag lock, or a pilot chute in tow may result. This can happen with a ripcord system, a pull out, or a throw out, if the pilot chute problem is bad enough. Most, but not all pilot chutes from container manufacturers are compatible with Performance Designs canopies. A pilot chute made from normal F-111 type fabric should be no more than 34" in diameter. We have found 30" to 32" to be adequate for most sport sized canopies (all measurements are finished dimensions). Pilot chutes made of zero porosity fabric are more sensitive to specific design criteria, and two of similar size may have widely different drag. They are definitely more sensitive to variations in design, with factors such as mesh size and hole size at the pilot chute base making a big difference in the drag produced. The zero porosity pilot chutes that we have tried that work adequately are between 26" and 28" and have relatively fine mesh. These pilot chutes also seem to be more sensitive to variations in line stow length and line stow tightness than regular pilot chutes. Quote Share this post Link to post Share on other sites
cobaltdan 0 #28 December 23, 2003 Atair is exceedingly busy and expanding rapidly. Between building a new factory, increasing staff 50%, and military and sport production production my free time is non existant. as such i have not been dropzone.com in some time. (please do not pm me here, if you need to reach me contact the office via phone, thanks) i glazed over this thread and wanted to point out: - 22-24" pilot chutes were recommended because we recorded scientific data that showed us that a jumper could not tell the difference between a high shock caused at line stretch by a pilot chute (before the canopy leaves the bag), and a shock caused by the canopy leaving the bag and inflating. This is increasingly the case as speed increases and becomes a serious safety issue at freefly speeds. -we developed the cobalt canopy to reduce the risk of breaking your neck by a high speed deployment. if you are going to fly at 180mph your canopy should be able to open at 180mph with a force vs. time curve that is safe. this this IS effected by pilot chute size, that is for ANY canopy. using a datalogger and strain gauges on the risers you can distinctly resolve the forces subjected to a jumper during line stretch and then for all stages of a canopy deployment. we measured the force vs. time curve for pilot chutes of 18" to 30" in 2" increments. from memory at 120 mph the 22" is over 80 # pull. using a pilot chute that has more pull than necessary at 120mph just makes things worse for you in the event of a high speed premature deployment. additionally as pointed out in the past, please compare apples to apples, not every manufacturer measures the same. some manufactures that argue not to use a 22" actually manufacturer that size and call it a 24". happy holidays to all ! sincerely, daniel preston atair aerodynamics www.extremefly.com ps it was never a fix and always a recommendationDaniel Preston <><> atairaerodynamics.com (sport) atairaerospace.com (military) Quote Share this post Link to post Share on other sites
3ringheathen 0 #29 December 23, 2003 AFAIK, the smaller pilot chute has always been recomended. -Josh If you have time to panic, you have time to do something more productive. -Me* *Ron has accused me of plagiarizing this quote. He attributes it to Douglas Adams. Quote Share this post Link to post Share on other sites
3ringheathen 0 #30 December 23, 2003 QuoteQuoteAccording to your profile, you are jumping a Sharpchuter 245. Hardly a high performance canopy, and therefore, completely irrelevant to to my point. -Josh I have spent over 20 years involved in the testing and development of parachutes and parachute systems. Is that relevant to understanding the function and relationship of the various component parts of a parachute system? Apparently not. I don't know how many different ways I have to state this: Pilot chute size is *one* factor that effects openings. It's not the only factor, and certainly not the single most important factor. Never the less, it is a factor. Period. For some canopies, it's minor factor, for others it plays a more significant role. Canopy design is a delicate balance of a bunch of different factors and desired performance characteristics. It's safe to say that the Sharpchuter is not a high performance canopy, so it's no surprise that it's more tolerant of different PC sizes. The canopy is heavy enough that any pilot chute that will extract it from the bag will be satisfactory. Many crossbraced canopies are also tolerant of different PC sizes. This shouldn't be surprising as the nose is mostly closed off, so it's going to take longer to inflate. For such canopies, PC size is *less* of an issue, but there are trade offs. They tend to be trimmed very steeply and are ground hungry, the front riser pressure becomes extremely high once a turn is induced, and pack volume and purchase price are higher. In my experience, the canopy that most closely matches the Cobalt is the Crossfire. Trade offs: Cobalt is more sensitive to PC size. Crossfire control stroke starts much lower, and it snivels a great deal. This can be inappropriate for low hop and pops, many owners opt to install larger sliders. How is that different than installing a smaller PC? -Josh If you have time to panic, you have time to do something more productive. -Me* *Ron has accused me of plagiarizing this quote. He attributes it to Douglas Adams. Quote Share this post Link to post Share on other sites
3ringheathen 0 #31 December 23, 2003 QuoteQuoteI'm not familiar with rubber band less Dbags on skydiving mains. Since you say they are "being developed" I'd imagine that it's new technology. As such it doesn't prove or disprove anything relative to the designs that are currently common place. QuoteBasically they use a pouch for stowing the lines and a set of tabs to keep the bag shut until line stretch. No tight rubber bands to prevent hard openings. At least one 4-way team has put a lot of jumps on them. A search should bring up several threads on them. What kind of canopies are they jumping? As I've stated, line stows are *one* factor. If a 4 way team is jumping a canopy that is less effected than most by stow tension, it doesn't follow that stow tension is not a factor in hard openings. QuoteSticking with the automotive analogy, just because some newer cars don't have distributors, doesn't mean that those that rely on them aren't susceptible to problems from water in the distributor cap. Quote Stiching with the automotive analogy? Who used an automotive analogy? I used the automotive analogy in the thread that this spun off of. You were there, didn't you read my posts before you replied to them? QuoteYou can't compare apples and oranges. Quote When did I compare apples to oranges? You said tight rubber bands help prevent hard openings. I countered that with the example of a d-bag that uses no rubber bands and only locking stows that is not producing hard openings to show that tight rubber bands are not necessary for soft openings. I never said tight line stows were *necessary* for soft openings. Only that they are a factor. Quote A wide variety? Not compared to what exists today. Quote If the reserve PC made that big of a difference, they would have either failed because the PC was too big, or not opened within the altitude specified because the reserve PC was too small. Since they received TSO certification, this wasn’t the case. As I stated previously, a reserve is a different animal than a main. The goal is to get it open as fast as possible. There's no reason to put a smaller PC on a reserve. That doesn't mean that a smaller PC wouldn't work, but why bother? What would you hope to gain? Quote Yes, you are confused. I didn't say that reserves aren't affected by PC size. I said that you want a reserve to open as fast as possible, so you naturally put a large pilot chute on it. Quote Yes, I was/am confused. It's beginning to look like your confusion comes from failing to head the advice that appears in your sig file. No flames or insult intended, but you've been arguing things that I have not said, and ignored or overlooked things that I have stated. It's hard to reach any sort of understanding under those circumstances. Quote I'm not saying that a PD 106R wouldn't open hard with a large *PC* (*reserve*was a typo). I'm saying exactly the opposite. QuoteAre you saying a PD-106R opens harder than a PD-281R deployed out of the same type of container because they both have the same size reserve PC? No. It might open harder, but probably not significantly so. A reserve is designed to open fast to begin with. They have large, wide open noses, seven cells, small or ported sliders, and free bags. One of the reasons a large PC can cause harder openings is because of the canopy distortion associated with excessive snatch force/center cell stripping. Since a freebag isn't attached to a the canopy, much if not all, of this force is eliminated. Quote Fair enough, but your anecdotal and limited experience pail in comparison to the rigorous experimentation that companies such as PD perform. No insult intended, but a typical PD test pilot has far more jumps under far more strictly controlled circumstances than you and I combined are ever likely to accumulate, and they've reached different conclusions than you have. If you know anything about the scientific method, you know that anecdotal evidence doesn't mean all that much. Quote True enough, but I do know the difference between a hard and soft opening. I have put over 500 jumps on a single canopy, 3 different times. How many test jumps does PD put on a single size/type canopy before releasing it? A lot more than that! Quote I also know that PD claims that Sabre’s don’t open hard. I have learned that manufacturers aren’t the end-all of gear information. If they were, we wouldn’t ever need SB’s and AD’s. I agree, that was the point I was trying to make when Aggie Dave suggested that Rig manufacturers opinions are definitive. -Josh If you have time to panic, you have time to do something more productive. -Me* *Ron has accused me of plagiarizing this quote. He attributes it to Douglas Adams. Quote Share this post Link to post Share on other sites 3ringheathen 0 #32 December 23, 2003 QuoteQuoteHow about my Jedei 136? that high proformance enough? I've got 200 jumps with no stows and 200 stowed on it and can't tell the difference. All open the same. A single canopy design, let alone a single version of it, proves absolutely nothing about general factors in parachute openings. From the Icarus Canopy owners manual: We recommend making a double turn with all stow bands, to help prevent line dump. Quote Bill Booth can answer this question better then anyone seeing as he practially invented the hand deploy PC Maybe you should ask him yourself. He seems to think that PC size can affect openings: "...pilot chute size vs. the weight of your main canopy affects seperation velocity, snatch force, opening shock, and malfunction rate. More about these another time.Bill Booth..." -Josh If you have time to panic, you have time to do something more productive. -Me* *Ron has accused me of plagiarizing this quote. He attributes it to Douglas Adams. Quote Share this post Link to post Share on other sites mjosparky 3 #33 December 23, 2003 My original statement was:QuoteA PC may affect the snatch force to some degree but will have no effect on the opening shock. As the canopy starts to open the PC stops functioning completely. *** Daniel Preston stated:*** 22-24" pilot chutes were recommended because we recorded scientific data that showed us that a jumper could not tell the difference between a high shock caused at line stretch by a pilot chute (before the canopy leaves the bag), and a shock caused by the canopy leaving the bag and inflating. The high shock at line stretch he refers to is "snatch force". This can be effected by the drag coefficient of the PC. The other shock he refers to is "opening shock". This the force the canopy creates during deplopment. At this point the PC has lost most if not all of its drag in the shadow of the the canopy. They are 2 distinct things but happen so fast that can feel like one. Why would the fact that I jump a Sharpchuter have anything to do with my ability to understand canopy deployment? Believe me that is not the only canopy I have jumped.My idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites 3ringheathen 0 #34 December 23, 2003 QuoteQuoteMy original statement was:***A PC may affect the snatch force to some degree but will have no effect on the opening shock. As the canopy starts to open the PC stops functioning completely. *** Your original statement also included the following: "I have been jumping a main D-bag with just 2 locking stows and the rest of the lines in a pouch for several years. I find there is no difference in the opening when using this bag or a bag with all lines stowed...." QuoteWhy would the fact that I jump a Sharpchuter have anything to do with my ability to understand canopy deployment? Believe me that is not the only canopy I have jumped. Your choice of main doesn't prevent you from understanding canopy deployment, but it is likely to influence it. However, you cited your experience with the limited stow d-bag as some sort of proof that line stows don't effect openings. Maybe I assumed too much, and if so I aplogize, but I gathered that you've been jumping this d-bag on your primary canopy. Your experiences with a large, seven cell accuracy canopy do not prove anything at all about general factors involved in openings. Further, as Rob pointed out, you still have the most critical stows on that kind of bag. That would be the locking stows, which help to insure that the slider stays against the pack job until line stretch. The error in logic that those of you in the stows-and-PCs-don't-effect-openings camp seem to be making is at least two fold: 1) Assuming that the deceleration provided by tight line stows is what's important, and 2) Assuming that your experiences with a small sample of canopies can be extrapolated to all canopies. -Josh If you have time to panic, you have time to do something more productive. -Me* *Ron has accused me of plagiarizing this quote. He attributes it to Douglas Adams. Quote Share this post Link to post Share on other sites riggerrob 558 #35 December 23, 2003 Josh, Reading your comments here is great entertainment. Would you mind doing me a favor? Please run around Snohomish and give "happy holiday hugs" to all my old friends. Quote Share this post Link to post Share on other sites mjosparky 3 #36 December 23, 2003 QuoteThe error in logic that those of you in the stows-and-PCs-don't-effect-openings camp seem to be making is at least two fold: 1) Assuming that the deceleration provided by tight line stows is what's important, and 2) Assuming that your experiences with a small sample of canopies can be extrapolated to all canopies. -Josh Josh, I have over 500 jumps on canopies ranging from 170 to 230 without the use of any D-bag at all, and using PC's from 26" to a 7 vane 30". It appears to me that you are the one "assuming" what my experience is with any size sample of canopies is. If you re-read my posts you will find I did not mention tight line stows or the deceleration they provide.My idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites TALONSKY 0 #37 December 23, 2003 The error in logic that those of you in the stows-and-PCs-don't-effect-openings camp seem to be making is at least two fold: 1) Assuming that the deceleration provided by tight line stows is what's important, and 2) Assuming that your experiences with a small sample of canopies can be extrapolated to all canopies. -Josh I do not know about the others but the point I have made and I have yet to see a tangible argument on it. Pilot chute size may make a difference but how come no other manufacturer’s out there request a change in PC size for their canopies. If PC size really made a huge impact on opening then would it not make sense that other manufactures would be requesting PC size change. In the end I am sure PC size has an effect on opening but if the canopy is designed well they are not that sensitive to PC size. I have jumped a Falcon 195, a Safire 169, a Crossfire 129, a Crossfire 2 130, and a VX 109 all with the same size of PC and had great openings on all of them. Now I will add the Falcon started opening hard at about 1000 jumps on it (I am quite sure it was way out of trim) and it did take me a few jumps on the VX to figure out how to pack it in order not to have hard openings. That aside all did not need any fix’s to get them to open nice. You may go on and on about snatch forces and PC size but really I have yet to see other manufactures requesting a change of PC size to get nice openings as a standard part of using their canopies. Kirk Quote Share this post Link to post Share on other sites cloud9 0 #38 December 23, 2003 Quote I do not know about the others but the point I have made and I have yet to see a tangible argument on it. Pilot chute size may make a difference but how come no other manufacturer’s out there request a change in PC size for their canopies. From Atair: "using a pilot chute that has more pull than necessary at 120mph just makes things worse for you in the event of a high speed premature deployment." I think it was answered, because Atair feels like a deployment at high speeds on a Cobalt will be survivable, and the worst part could be the pilot chute. I don't know if its true or not but it explains why they recommend the smaller size. The other manufacturers don't make the same claim on high speed deployments. Quote Share this post Link to post Share on other sites TALONSKY 0 #39 December 23, 2003 Touché , that answers part of the reason why they request it on all Cobalt’s, however it still remains that when a customer has a hard opening Cobalt at standard terminal velocity one of Atair’s fixes is to go to a smaller Pilot Chute. Which still leave the question of why does a Cobalt need a smaller pilot chute to get good openings when no other manufacturer’s canopy does? Kirk Quote Share this post Link to post Share on other sites DBCOOPER 1 #40 December 23, 2003 Quotehowever it still remains that when a customer has a hard opening Cobalt at standard terminal velocity one of Atair’s fixes is to go to a smaller Pilot Chute Quotedaniel preston atair aerodynamics www.extremefly.com ps it was never a fix and always a recommendation From the Atair web page I am experiencing hard openings, what could be the problem? Please follow our checklist if you are having hard openings: 1) Did you read the "Atair 2-stage deployment" tech sheet? If not please do so. You will not fully enjoy your equipment if you do not use it correctly. 2) What diameter is your pilot chute? Is it f111 or ZP? Is it kill line? Recommended pilot for cobalt 150-170 is a 24” zero-p kill line collapsible. Recommended pilot for Cobalts 65-135 is a 22"-24" zero-p kill line collapsible. Note: many containers come standard with a 28-32" pilot. This is more than double the recommended surface area required. A 28" pilot will cause brisk openings especially at higher speeds.Replying to: Re: Stall On Jump Run Emergency Procedure? by billvon If the plane is unrecoverable then exiting is a very very good idea. Quote Share this post Link to post Share on other sites Prev 1 2 Next Page 2 of 2 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. 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3ringheathen 0 #32 December 23, 2003 QuoteQuoteHow about my Jedei 136? that high proformance enough? I've got 200 jumps with no stows and 200 stowed on it and can't tell the difference. All open the same. A single canopy design, let alone a single version of it, proves absolutely nothing about general factors in parachute openings. From the Icarus Canopy owners manual: We recommend making a double turn with all stow bands, to help prevent line dump. Quote Bill Booth can answer this question better then anyone seeing as he practially invented the hand deploy PC Maybe you should ask him yourself. He seems to think that PC size can affect openings: "...pilot chute size vs. the weight of your main canopy affects seperation velocity, snatch force, opening shock, and malfunction rate. More about these another time.Bill Booth..." -Josh If you have time to panic, you have time to do something more productive. -Me* *Ron has accused me of plagiarizing this quote. He attributes it to Douglas Adams. Quote Share this post Link to post Share on other sites
mjosparky 3 #33 December 23, 2003 My original statement was:QuoteA PC may affect the snatch force to some degree but will have no effect on the opening shock. As the canopy starts to open the PC stops functioning completely. *** Daniel Preston stated:*** 22-24" pilot chutes were recommended because we recorded scientific data that showed us that a jumper could not tell the difference between a high shock caused at line stretch by a pilot chute (before the canopy leaves the bag), and a shock caused by the canopy leaving the bag and inflating. The high shock at line stretch he refers to is "snatch force". This can be effected by the drag coefficient of the PC. The other shock he refers to is "opening shock". This the force the canopy creates during deplopment. At this point the PC has lost most if not all of its drag in the shadow of the the canopy. They are 2 distinct things but happen so fast that can feel like one. Why would the fact that I jump a Sharpchuter have anything to do with my ability to understand canopy deployment? Believe me that is not the only canopy I have jumped.My idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
3ringheathen 0 #34 December 23, 2003 QuoteQuoteMy original statement was:***A PC may affect the snatch force to some degree but will have no effect on the opening shock. As the canopy starts to open the PC stops functioning completely. *** Your original statement also included the following: "I have been jumping a main D-bag with just 2 locking stows and the rest of the lines in a pouch for several years. I find there is no difference in the opening when using this bag or a bag with all lines stowed...." QuoteWhy would the fact that I jump a Sharpchuter have anything to do with my ability to understand canopy deployment? Believe me that is not the only canopy I have jumped. Your choice of main doesn't prevent you from understanding canopy deployment, but it is likely to influence it. However, you cited your experience with the limited stow d-bag as some sort of proof that line stows don't effect openings. Maybe I assumed too much, and if so I aplogize, but I gathered that you've been jumping this d-bag on your primary canopy. Your experiences with a large, seven cell accuracy canopy do not prove anything at all about general factors involved in openings. Further, as Rob pointed out, you still have the most critical stows on that kind of bag. That would be the locking stows, which help to insure that the slider stays against the pack job until line stretch. The error in logic that those of you in the stows-and-PCs-don't-effect-openings camp seem to be making is at least two fold: 1) Assuming that the deceleration provided by tight line stows is what's important, and 2) Assuming that your experiences with a small sample of canopies can be extrapolated to all canopies. -Josh If you have time to panic, you have time to do something more productive. -Me* *Ron has accused me of plagiarizing this quote. He attributes it to Douglas Adams. Quote Share this post Link to post Share on other sites
riggerrob 558 #35 December 23, 2003 Josh, Reading your comments here is great entertainment. Would you mind doing me a favor? Please run around Snohomish and give "happy holiday hugs" to all my old friends. Quote Share this post Link to post Share on other sites
mjosparky 3 #36 December 23, 2003 QuoteThe error in logic that those of you in the stows-and-PCs-don't-effect-openings camp seem to be making is at least two fold: 1) Assuming that the deceleration provided by tight line stows is what's important, and 2) Assuming that your experiences with a small sample of canopies can be extrapolated to all canopies. -Josh Josh, I have over 500 jumps on canopies ranging from 170 to 230 without the use of any D-bag at all, and using PC's from 26" to a 7 vane 30". It appears to me that you are the one "assuming" what my experience is with any size sample of canopies is. If you re-read my posts you will find I did not mention tight line stows or the deceleration they provide.My idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
TALONSKY 0 #37 December 23, 2003 The error in logic that those of you in the stows-and-PCs-don't-effect-openings camp seem to be making is at least two fold: 1) Assuming that the deceleration provided by tight line stows is what's important, and 2) Assuming that your experiences with a small sample of canopies can be extrapolated to all canopies. -Josh I do not know about the others but the point I have made and I have yet to see a tangible argument on it. Pilot chute size may make a difference but how come no other manufacturer’s out there request a change in PC size for their canopies. If PC size really made a huge impact on opening then would it not make sense that other manufactures would be requesting PC size change. In the end I am sure PC size has an effect on opening but if the canopy is designed well they are not that sensitive to PC size. I have jumped a Falcon 195, a Safire 169, a Crossfire 129, a Crossfire 2 130, and a VX 109 all with the same size of PC and had great openings on all of them. Now I will add the Falcon started opening hard at about 1000 jumps on it (I am quite sure it was way out of trim) and it did take me a few jumps on the VX to figure out how to pack it in order not to have hard openings. That aside all did not need any fix’s to get them to open nice. You may go on and on about snatch forces and PC size but really I have yet to see other manufactures requesting a change of PC size to get nice openings as a standard part of using their canopies. Kirk Quote Share this post Link to post Share on other sites
cloud9 0 #38 December 23, 2003 Quote I do not know about the others but the point I have made and I have yet to see a tangible argument on it. Pilot chute size may make a difference but how come no other manufacturer’s out there request a change in PC size for their canopies. From Atair: "using a pilot chute that has more pull than necessary at 120mph just makes things worse for you in the event of a high speed premature deployment." I think it was answered, because Atair feels like a deployment at high speeds on a Cobalt will be survivable, and the worst part could be the pilot chute. I don't know if its true or not but it explains why they recommend the smaller size. The other manufacturers don't make the same claim on high speed deployments. Quote Share this post Link to post Share on other sites
TALONSKY 0 #39 December 23, 2003 Touché , that answers part of the reason why they request it on all Cobalt’s, however it still remains that when a customer has a hard opening Cobalt at standard terminal velocity one of Atair’s fixes is to go to a smaller Pilot Chute. Which still leave the question of why does a Cobalt need a smaller pilot chute to get good openings when no other manufacturer’s canopy does? Kirk Quote Share this post Link to post Share on other sites
DBCOOPER 1 #40 December 23, 2003 Quotehowever it still remains that when a customer has a hard opening Cobalt at standard terminal velocity one of Atair’s fixes is to go to a smaller Pilot Chute Quotedaniel preston atair aerodynamics www.extremefly.com ps it was never a fix and always a recommendation From the Atair web page I am experiencing hard openings, what could be the problem? Please follow our checklist if you are having hard openings: 1) Did you read the "Atair 2-stage deployment" tech sheet? If not please do so. You will not fully enjoy your equipment if you do not use it correctly. 2) What diameter is your pilot chute? Is it f111 or ZP? Is it kill line? Recommended pilot for cobalt 150-170 is a 24” zero-p kill line collapsible. Recommended pilot for Cobalts 65-135 is a 22"-24" zero-p kill line collapsible. Note: many containers come standard with a 28-32" pilot. This is more than double the recommended surface area required. A 28" pilot will cause brisk openings especially at higher speeds.Replying to: Re: Stall On Jump Run Emergency Procedure? by billvon If the plane is unrecoverable then exiting is a very very good idea. Quote Share this post Link to post Share on other sites
