dzpilot 0 #1 October 29, 2009 Is there any hard rule to the relationship between main and reserve sizing: ie 160 main 160 reserve. I am down sizing from a 160 main to a 149 main and have a 160 smart reserve. any and all comments thanks. Quote Share this post Link to post Share on other sites
councilman24 36 #2 October 29, 2009 You'll get all sorts of answers. They should be the same, they don't need to be the same, the reserve should be bigger, etc. etc. etc. Any answer with a 'hard rule' is an OPINION. Unfortunately often times the container size combinations from the manufacturer of choice dictate the limts of the decision. My bottom line, most people shouldn't be jumping a non zp 7 cell that is as small as their main, and as small as the largest the container sized for their main will allow. But many get away with it. For your situation. Don't worry about needing a smaller reserve. Just make sure it's big enough. I'm old for my age. Terry Urban D-8631 FAA DPRE Quote Share this post Link to post Share on other sites
dzpilot 0 #3 October 29, 2009 Thanks, I didn't feel I had a problem however when I thought about it the question came to mind. Is there a rule? I have survived 25,000 hrs of flight time by learning from the mistakes of others, no sense stopping now. Quote Share this post Link to post Share on other sites
tetra316 0 #4 October 29, 2009 I have a PD 143 reserve that I bought for my first rig at 50 jumps. My mains started at a PD 170 down to a katana 107. I do not ever plan on downsizing my reserve regardless of what size or type of main I have. Quote Share this post Link to post Share on other sites
kingbunky 3 #5 October 29, 2009 mine are about the same size (170 main, 175 reserve) because i figure if i need my reserve, things are already going wrong, don't need to throw a downsized canopy into the mix. bad enough it's one i haven't jumped. most of the discussion takes place around how the canopies will behave in a two out situation and there are as many opinions as there are possible combinations. i don't know what your experience level is (profiles people, profiles! at least the skydiving info), but the combination you are considering seems okay, if the main size is appropriate."Hang on a sec, the young'uns are throwin' beer cans at a golf cart." MB4252 TDS699 killing threads since 2001 Quote Share this post Link to post Share on other sites
councilman24 36 #6 October 29, 2009 In the old days, early ram air reserves, the reserve was almost always smaller because they didn't come as big as the mains. And most of us couldn't jump a canopy that small, or didn't want to. In the not quite so old days reserves came out in the same sizes as mains. Either the same canopy (Raven's) or similar canopeis with small changes (Glide Path). Some people bought matching sets. (Even matching colors but not a good idea to not be able to tell quickly which is out, main or reserve) Partly because they wanted to land a reserve that was the same as their main and partly because we believed that two similar sized canopies would behave better together. Others believed that they SHOULDN'T be the same size because canopies with two different line lengths can form a biplane easier if two out. (BTW two out is the only reason I can think of that size RELATIONSHIP comes into discussion. Other than what combinations of size a container manufacturer offers.) Now, with most mains being much higher performance and for many people much smaller than the reserve they SHOULD jump it IMHO it just doesn't matter anymore. The main isn't going to behave with much of anything. My oldtimer advice? Get a reserve that it appropriate for you and hope you can get a container that will hold your choosen main. For newbies not much of an issue. Or old, injured farts like me. For pilots flying pocket rockets they may be forced to choose a reserve that is smaller than optimum. (Hmmm, I'm being nice in my language today.) Rule? No, just lots of opinion. Read this http://www.performancedesigns.com/docs/dualsq.pdf and PD's reserve flight characteristic document http://www.performancedesigns.com/docs/Reserve-Flight-Char-v3.pdf for more discussion. I'm old for my age. Terry Urban D-8631 FAA DPRE Quote Share this post Link to post Share on other sites
dragon2 0 #7 October 29, 2009 Get a reserve you can land safely anywhere, under any conditions, without problems. Then it's the right size Generally for a newer jumper (and for smart not-so-new jumpers) that's a wingload of 1:1 or less. Bigger is better in a reserve ciel bleu, Saskia Quote Share this post Link to post Share on other sites
freeatlast 0 #8 October 29, 2009 Quote Get a reserve you can land safely anywhere, under any conditions, without problems. Then it's the right size Generally for a newer jumper (and for smart not-so-new jumpers) that's a wingload of 1:1 or less. Bigger is better in a reserve Just remember that in the worst case scenario - YOU will not be landing the canopy at all - it will be landing itself! Therefore Bigger is DEFINATELY better (in my opinion) .... Quote Share this post Link to post Share on other sites
dzpilot 0 #9 October 29, 2009 thanks everyone....I agree I would like to stay with the biggest reserve I can which is my smart 160 that keeps the WL at 1.13 for me. Quote Share this post Link to post Share on other sites
Gary73 8 #10 October 30, 2009 Considering that your next reserve deployment may be at (or above) terminal velocity, never exceed the maximum recommended exit weight on a reserve. If you want to downsize your main below the limits of your current container, talk to your rigger about padding the main D-bag. It's fairly easy and allows significant downsizing without changing the container or reserve. "Extraordinary claims require extraordinary evidence." - Carl Sagan Quote Share this post Link to post Share on other sites
Bertt 0 #11 October 30, 2009 When you read the "Dual Square Report" referenced by Councilman24, keep in mind that it's not a "Square Reserve, Highly Tapered Main" report. You should read and understand it, but it's my opinion that it's less relevant to most skydivers now than when it was written.You don't have to outrun the bear. Quote Share this post Link to post Share on other sites
dragon2 0 #12 October 30, 2009 Quote When you read the "Dual Square Report" referenced by Councilman24, keep in mind that it's not a "Square Reserve, Highly Tapered Main" report. You should read and understand it, but it's my opinion that it's less relevant to most skydivers now than when it was written. Enevn when I had a 2out with a student 230 and a 250-ish student reserve (thanx to FXC fire @ 2.5k), they still downplaned on me after 1000ft of flying in a staggered plane. These were very similar canopies and they still wouldn't play well with each other. I'd never pick a reserve based on the main size, just pick a reserve you can land well anywhere and pick a main you like to fly. ciel bleu, Saskia Quote Share this post Link to post Share on other sites
skydiverek 60 #13 October 30, 2009 Quotethey still downplaned on me after 1000ft of flying in a staggered plane. Did you mean BIPLANE? Quote Share this post Link to post Share on other sites
dragon2 0 #14 October 30, 2009 QuoteQuotethey still downplaned on me after 1000ft of flying in a staggered plane. Did you mean BIPLANE? Main in front, reserve in back, staggered a bit so not quite straight behind each other. ciel bleu, Saskia Quote Share this post Link to post Share on other sites