rmcvey 0 #1 February 1, 2003 I jump an Atair Cobalt and have read on numerous occasions Atair recomends a 22" PC for a 135sqft canopy, and i seem to remember a 20" for sub 120???? Annnyway... Ive got a new rig, and jumped it for the first time today. and when ordering a rig i stated i wanted a 22" PC. After a chat with the manufacturer i decided to go with a 24" ZP collapsable Pilotchute, a size bigger than Atair recomends. So i dump at 3500 like usual and wait. and wait a bit more. hhhm getting nervous now, doesnt usually take this long..............pooof, canopy starts opening. I would say it took around 3 seconds, 4 at the most, before i felt anything. So i jumped it again to make sure it wasnt a hesitation or what not. Same again, about 3 seconds (i counted this time) from lobbing the pc to feeling any sort reaction (ie risers lifting off my back) Any thoughts?? new PC needed?? Quote Share this post Link to post Share on other sites
hookitt 1 #2 February 1, 2003 If you can deal with that type of hesitation feel again, get a video of the opening. *what brand pilot chute? *What type and size of cantainer do you have? *how tight does the main fit into the main packtray *How long is the bridle from the pin to the base of the pilot chute? Here are the search results from a search on Pilot Chute Size. There are many discussions and also posts from People like Bill Booth.My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto Quote Share this post Link to post Share on other sites
rmcvey 0 #3 February 1, 2003 i looked through the search results and found this: *** Go with manufacturers recommendation. But, if you get given or find something that works for you. Stick with that. I now favour the old, 'if it's not broke don't fix it' rule. I say this becasue I had an interesting experiment with pilotchute size. I fly a Cobalt 135. I was using the the standard 28" ZP pilotchute that came with my container. Out of about 20 jumps, 16 or 17 would be beautiful. I'd get the very occasional brisk opening and a few off headers. Pretty good stats considering all the variables that come into play at opening time. But I thought I could get 20 out of 20 picture perfect with the recommended pilot chute (22" ZP). So I put a new 22" ZP PC on and wham. I got a noticeable delay in bag liftout and then 3 absolute slammers. I tried dumping slow, fast and in a track. Same thing, hesy then whack. Why? Who knows. I put my old 28" back on and am enjoying lovely two stage openings again. If the occasional one is brisk and a few are off heading that's fine.Quote On my second jump i also had an unusually hard opening (my neck is hurting now) but have no idea why it happened. Im also realising now that my canopy/container choice may be the cause. Im jumping a Wings W5 (should fit 100-120sqft) with a 135. Is the the bag getting stuck in the corners of the container??? This would explain things. Is there a different way i can pack my container so the bag is extracted easier?? (Yes, i know your gonna flame me about bad kit combination) Quote Share this post Link to post Share on other sites rgoper 0 #4 February 1, 2003 QuoteAtair recomends a 22" PC for a 135sqft canopy i'd have to go with manufacturer's specs on this one, there is a reason for it. although, having said that, i was flying a Hornet with a 36" zp/pc/bridle before i purchased my Cobalt (both 170's^2) and the Hornet opened better, i jumped the Cobalt with the 36" zp/pc/bridle first jump, opening, etc was perfect. then i went to Atair's specs (i already had it with me at the dz that day) and changed over to the 24" zp/pc/bridle, now i never changed back to the 36" set, but my life with the Cobalt has been a living hell ever since. i'm not a mechanical engineer, but i know that container manufacturer's send out what they deem acceptable for any canopy size range that will fit into the container, no matter what "Brand" your flying.--Richard-- "We Will Not Be Shaken By Thugs, And Terroist" Quote Share this post Link to post Share on other sites cobaltdan 0 #5 February 1, 2003 we recommend a "jim cazer" manufactured 22" zp collapsable for our canopies up to 135 and a 24" for canopies over. a properly manufactured 22" pilot has far more drag force than required to open any small-medium size container and canopy, ditto for a 24" and larger canopies. anything larger is unnecessary and can adversly effect line snatch force, deployment, and equipment wear. construction techniques that you can get away with on larger pilots, is not up to par on smaller ones. hence the misconception that smaller pilots do not work well. additionally there is a discrepency in how people lable size, i.e. cut size or sewn size? of all pilots chutes we have seen jim cazer and rws are the only ones manufactured correctly for use in small sizes. btw bill booth told me while inspecting our 22" pilot is that rws will be making a similar standard size. bill confirmed all the correct construction techniques on the jim cazer design and explained the construction errors of other manufacturers to me. perhaps he will post some comments. as far as the posters delay of 3-4 seconds. there is something wrong with your pilot chute. sincerely, daniel preston atair aerodynamics www.extremefly.comDaniel Preston <><> atairaerodynamics.com (sport) atairaerospace.com (military) Quote Share this post Link to post Share on other sites hookitt 1 #6 February 1, 2003 <> rmcvey, The question I forgot to include, What brand pilot chute are you using? I will certainly make an attempt to use a 20 or 22 inch pilot chute in the future just to satisfy my own curiosity of it's affectiveness. If I don't try it, I can not comment on it. Edit: I erased a comment, I felt was unnecessary,My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto Quote Share this post Link to post Share on other sites rmcvey 0 #7 February 2, 2003 The Pilotchute came from Wings. I specifically asked for a 24" ZP. Ive tested to see how the apex compares to the skirt and it is about 1.5" below the skirt when held upside down. Ive measured the diameter of the pilotchute when laid out flat, and it measures 22". ????? 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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rgoper 0 #4 February 1, 2003 QuoteAtair recomends a 22" PC for a 135sqft canopy i'd have to go with manufacturer's specs on this one, there is a reason for it. although, having said that, i was flying a Hornet with a 36" zp/pc/bridle before i purchased my Cobalt (both 170's^2) and the Hornet opened better, i jumped the Cobalt with the 36" zp/pc/bridle first jump, opening, etc was perfect. then i went to Atair's specs (i already had it with me at the dz that day) and changed over to the 24" zp/pc/bridle, now i never changed back to the 36" set, but my life with the Cobalt has been a living hell ever since. i'm not a mechanical engineer, but i know that container manufacturer's send out what they deem acceptable for any canopy size range that will fit into the container, no matter what "Brand" your flying.--Richard-- "We Will Not Be Shaken By Thugs, And Terroist" Quote Share this post Link to post Share on other sites
cobaltdan 0 #5 February 1, 2003 we recommend a "jim cazer" manufactured 22" zp collapsable for our canopies up to 135 and a 24" for canopies over. a properly manufactured 22" pilot has far more drag force than required to open any small-medium size container and canopy, ditto for a 24" and larger canopies. anything larger is unnecessary and can adversly effect line snatch force, deployment, and equipment wear. construction techniques that you can get away with on larger pilots, is not up to par on smaller ones. hence the misconception that smaller pilots do not work well. additionally there is a discrepency in how people lable size, i.e. cut size or sewn size? of all pilots chutes we have seen jim cazer and rws are the only ones manufactured correctly for use in small sizes. btw bill booth told me while inspecting our 22" pilot is that rws will be making a similar standard size. bill confirmed all the correct construction techniques on the jim cazer design and explained the construction errors of other manufacturers to me. perhaps he will post some comments. as far as the posters delay of 3-4 seconds. there is something wrong with your pilot chute. sincerely, daniel preston atair aerodynamics www.extremefly.comDaniel Preston <><> atairaerodynamics.com (sport) atairaerospace.com (military) Quote Share this post Link to post Share on other sites
hookitt 1 #6 February 1, 2003 <> rmcvey, The question I forgot to include, What brand pilot chute are you using? I will certainly make an attempt to use a 20 or 22 inch pilot chute in the future just to satisfy my own curiosity of it's affectiveness. If I don't try it, I can not comment on it. Edit: I erased a comment, I felt was unnecessary,My grammar sometimes resembles that of magnetic refrigerator poetry... Ghetto Quote Share this post Link to post Share on other sites
rmcvey 0 #7 February 2, 2003 The Pilotchute came from Wings. I specifically asked for a 24" ZP. Ive tested to see how the apex compares to the skirt and it is about 1.5" below the skirt when held upside down. Ive measured the diameter of the pilotchute when laid out flat, and it measures 22". ????? Quote Share this post Link to post Share on other sites
