JohnSherman 1 #26 November 9, 2013 40 years of running a loft and relining and retrimming canopies don't show any real difference in trim loss. Dacron will stretch the inside lines as they take the initial loading. Spectra will shrink the outside lines from the heat of the slider grommets. I find this to be an offset. I doubt that the coefficient of friction between the 2 is much different. We have found that Grommet material might be making difference as to the descent of the slider. SS is heaver than Brasss and the phototogs will tell you brass opens softer as the slider comes down slower. I have not personally examined this claim but it seems good on the first look. This would diminish the effect of the line friction theorie. It would not matter if the SPEED bag were used or not as long as it was used in both evaluations. I have made this evaluation both with and without the SPEED bag. SPEED bags don't open softer than regular bags they just do it consistantly, every time. They prevent the aborant opening. Sure Dacron has its place. Accuracy canopies come to mind as the increase drag helps slow the canopy down on approach. JS Quote Share this post Link to post Share on other sites
jumpsracer 5 #27 November 9, 2013 Nothing, and I mean Nothing, beats a FireBolt for openings. Call Nancy or Suzie at Jumpshack for a demo. You'll be surprised! Quote Share this post Link to post Share on other sites
erdnarob 1 #28 November 13, 2013 I am almost 15 years older than you and weight way more than 185. I jump a Katana 170. All depend on your shape and physical conditions. If you have the experience, skill...the Katana 170 will provide you with the softest openings like most of the fully elliptical canopies do. And even better, the Katana will flare powerfully. You can fly the Katana conservatively. It's a docile canopy unless you start to push it. The long toggles range makes that canopy not touchy at all. But never never do a sudden 180 degrees normal turn at low altitude since it sinks very fast. OTOH you can easily do flat turns.Learn from others mistakes, you will never live long enough to make them all. Quote Share this post Link to post Share on other sites
sralston 0 #29 November 13, 2013 FIREBOLT!!!!! I jumped a Saber 2 210 for about 70 jumps and then switched to a firebolt 236. My first jump I had to look up to make sure it had open it was so soft. Great landing also. Quote Share this post Link to post Share on other sites
jumpwally 0 #30 November 14, 2013 Really ? A Katana for someone who took a 14 yr break ? ....Wow,,just wow... smile, be nice, enjoy life FB # - 1083 Quote Share this post Link to post Share on other sites
erdnarob 1 #31 November 19, 2013 I missed the 14 years break. He was asking for something providing a soft opening. The Katana 170 is one answer. Now, before jumping it, he can make few jumps with a Sabre 2 which is the normal canopy to prepare you for the Katana. Again, it depends on his experience and skill and ...a good briefing. Again, the Katana 170 is a docile parachute when flown conservatively.Learn from others mistakes, you will never live long enough to make them all. Quote Share this post Link to post Share on other sites
masterrigger1 2 #32 November 20, 2013 Quote He was asking for something providing a soft opening. The Katana 170 is one answer. Have you ever jumped a Safire II, Crossfire 1 or II, or a Pilot? I am guessing not.... BTW,there are plenty of other canopies that open softer that a Katana and also not as heading sensitive as the Katana. Quote Again, the Katana 170 is a docile parachute when flown conservatively. You have got to be kiddingThe Katana has a high angle of attack and when flown simply straight, it still carries a lot of speed. MELSkyworks Parachute Service, LLC www.Skyworksparachuteservice.com Quote Share this post Link to post Share on other sites
likestojump 3 #33 November 20, 2013 masterrigger1 Quote He was asking for something providing a soft opening. The Katana 170 is one answer. Have you ever jumped a Safire II, Crossfire 1 or II, or a Pilot? I am guessing not.... BTW,there are plenty of other canopies that open softer that a Katana and also not as heading sensitive as the Katana. *** Again, the Katana 170 is a docile parachute when flown conservatively. You have got to be kiddingThe Katana has a high angle of attack and when flown simply straight, it still carries a lot of speed. MEL +1 Next thing we'll have people suggesting velocity 120's for 100 lbs girls because they are 7cell and fly very stable at low wingloadings. Quote Share this post Link to post Share on other sites
erdnarob 1 #34 November 20, 2013 I have jumped a Safire 1-209 and a Pilot 210. But my turn to ask you if you have tried the Katana 170. In many people mind, the Katana only exists in small sizes. Moreover, even at the same loading, a biggger parachute is reacting slower. I am loading mine at 1.6 and I repeat, it is not touchy as long as you are conservative, thanks to the long range toggles. I have about 600 jumps on mine. I have tried a Katana 150 and it provided me with the softest landing. The pitch angle of the Katana is the higher with 18 degrees. It is a great advantage and the added speed provides you extra soft landings which is good to save your bones. OTOH, I heard for the Safire 2 that the opening takes 1000 ft or so. For me it's too much. You never know when you will have to pull lower. Deploying a Safire 2 at the 2200 ft (the lowest legal) can bring you very near the AAD activation altitude (which is 260 ft higher when in a stand up position since there is no more differential pressure between chest and back). As I mentioned it, the choice of canopy depends on the jumper experience and skill. Learn from others mistakes, you will never live long enough to make them all. Quote Share this post Link to post Share on other sites
masterrigger1 2 #35 November 20, 2013 Quote A word about Spectra vs. Dacron: I see here in the form and have heard others repeatedly say that Spectra lined canopies open harder than Dacron lined canopies. I would like to take issue with this foible. I do not agree with this premise and see no proof other than subjective evaluation of the reported phenomenon. John, I just saw this post,,sorry I am late to respond. Again, the proof is in the pudding so to speak,. It is simple to prove that line material does make a difference in the openings. Simply put a spectra line set on a canopy, let someone test jump it, and then change the line set to other types and test jump it some more. We have! Now it is your turn if you do not believe it. Quote When I designed the Firebolt Tandem Main I was told (by the competition) that you could not use Spectra line on a Tandem canopy. Spectra was being used on the Strong SET 400, Flight Concepts canopies, and Precision Canopies before you built the Firebolt. Quote I have measure opening force loads, hundreds of times, on both Dacron and Spectra lined canopies and can see no difference in resultant force. I would love to see the data! The Army Demo Teams only will use Dacron on their canopies. Spectra is not allowed to be used. ( at least on their mains that I know of) Quote When I design a canopy I specify Spectra because it holds its trim better and has a better life is lighter and stronger. It might be lighter and stronger size for size, but it will not hold trim better. I have yet to see 12 plus inches of differential on a Dacron lined canopy like I have with Spectra. MELSkyworks Parachute Service, LLC www.Skyworksparachuteservice.com Quote Share this post Link to post Share on other sites
JohnSherman 1 #36 November 21, 2013 QuoteAgain, the proof is in the pudding so to speak,. It is simple to prove that line material does make a difference in the openings. Simply put a spectra line set on a canopy, let someone test jump it, and then change the line set to other types and test jump it some more. We have and we measured it with both force transducers and accelerometers. We did not depend on some subjective test jumper evaluation. We controlled the variables and used a Speed Bag which compensates for variations in line bulk. It was Booth who said you can't use Spectra on Tandem. I not only used it on the Firebolt but I used it on the original Tandem 400 which was by design a fast opener, now our tandem reserve. We pre-stretch all of our line, both Spectra and Dacron before marking and cutting. The only time I have ever seen the amount of stretch to which you refer is before pre-stretch. I wonder if the manufacturer of the product upon which you found this anomaly did. Quote Share this post Link to post Share on other sites
masterrigger1 2 #37 November 21, 2013 Quote We have and we measured it with both force transducers and accelerometers. We did not depend on some subjective test jumper evaluation. Well maybe you should use something different. The results are so diverse between two it is readily apparent to just about ant current jumper. I suggest you get some new equipment because yours can't be working correctly. Quote We pre-stretch all of our line, both Spectra and Dacron before marking and cutting. The only time I have ever seen the amount of stretch to which you refer is before pre-stretch. If you get your line from CSR (which most people do these days); it will come pre-stretched. Also, the manufacturer that built the canopy in question uses pre-stretched Spectra from CSR. MELSkyworks Parachute Service, LLC www.Skyworksparachuteservice.com Quote Share this post Link to post Share on other sites
skydiverek 55 #38 November 21, 2013 JohnShermanWe controlled the variables and used a Speed Bag which compensates for variations in line bulk. 99% of opening worldwide are NOT controled by Speedbag, and therefore Dacron CAN come handy! http://performancedesigns.com/faq.asp#8 The question is: have you packed a deliberate line-dump and measured forces in such scenario (with Spectra and Dacron)??? Quote Share this post Link to post Share on other sites
