BlindBrick 0 #1 May 24, 2004 Being a big jumper, I have been having a hell of a, no make that impossible, time finding a high performance canopy that won't put me at an isane wingloading for my experience and landing altitude. I'm to the point that I'm just about fustrated enough to try to make my own main. At my old dz, we hae a prototype canopy that never left that stage because ever landing resutled in broken legs. Given that, I want to try to make a half-way scientific approach to the design of the canopy. Can anyone recommend some texts that might help me with this? -Blind"If you end up in an alligator's jaws, naked, you probably did something to deserve it." Quote Share this post Link to post Share on other sites
markbaur 0 #2 May 24, 2004 The best text is an old canopy. Take it apart, make copies of the pieces, make a new canopy (or at least a couple of cells, perhaps including a stabilizer, perhaps the pilot chute attachment point). Your reproduction canopy is unlikely to be jumpable, but the exercise will give you an understanding of the construction process and materials, which in turn will be the basis of your design(s). Mark Quote Share this post Link to post Share on other sites
mjosparky 3 #3 May 24, 2004 See if you can locate a copy of "Performance, Design and Construction of Ram-Air inflated, Gliding parachute wings" by Manley Butler. It was written in 1985 but the principles still apply. http://www.butlerparachutes.com/ SparkyMy idea of a fair fight is clubbing baby seals Quote Share this post Link to post Share on other sites
slotperfect 7 #4 May 24, 2004 Another suggestion would be to send a shotgun email to different canopy manufacturers, providing your exit weight, experience level, DZ altitude, and desire to fly a high performance canopy. You are not the Lone Ranger in your situation, so they might just have a recommendation for you. There is a convenient list of some of those manufacturers (the ones that are registered dotcommers) stuck to the top of this forum. Good luck!Arrive Safely John Quote Share this post Link to post Share on other sites
darkwing 4 #5 May 24, 2004 I think there are really two issues here. One, locating a suitable performance enhanced canopy. I agree with the suggestion that you should contact some manufacturers. It looks to me like you would be looking for something about 250 sqft, and in the Sabre2/Pilot class. I will caution you about getting too zoomie, too quickly. Also you should contact Brian Germain, at Big Air Sportz. He is a great guy and builds excellent canopies. He might have a solution for you. The second issue is that of making canopies yourself. If you aren't an experienced rigger, then it would be a big, big job for you. As said above, your first canopy should be a copy of something, but unfortunatly there isn't something you want to copy, which means you need to do some engineering also, which is not a good way to start for your first time. You would end up spending a LOT of money and time getting a canopy which would be what you want. Think about raw materials, sewing machines, errors.... I have built canopies, and I don't recommend it for the beginner. -- Jeff My Skydiving History Quote Share this post Link to post Share on other sites
skydiver30960 0 #6 May 24, 2004 I'm with slotperfect and darkwing on this one... manufacturers have experience with everything from double digit square footage all the way up to fully loaded (and OVERloaded) tandem mains. How big is big, BlindBrick? Is your profile current, it lists 131 jumps, so I'm guessing you aren't looking for anything super-zippy-mega-crossbraced or anything like that, just something with a little more kick than the PD-9 cell you have listed? Are you thinking zero P square? Semi-elliptical? Even for your size, I'm still with slotperfect. If you aren't already an aeronautical engineer or have some SERIOUS experience with commercial sewing, it'll be a LONG time before you could make anything jumpable. Think about it, skydivers can be some cheap bastards, but how many of us are making our own canopies! I'm sure somebody out there will have something that meets your needs... Edit to add: "and darkwing" because great minds think alike, and post at the same time! Elvisio "so much sewing, so little time" Rodriguez Quote Share this post Link to post Share on other sites
slotperfect 7 #7 May 24, 2004 Chiming in on sd30960's input, aimed at BlindBrick: I am an experienced Rigger and I can sew very well. I would never take on building my own canopy. I am not a design engineer, nor do I feel I have the skills or experience from being apprenticed to a canopy manufacturer to do so. There is a perfect canopy, both in size and performance, out there somewhere for you. You may just have to be a bit more diligent in your search. Seek advice from the Instructors and Staff at your DZ that have seen you fly your current canopy. They can help you start looking in a safe size and performance range.Arrive Safely John Quote Share this post Link to post Share on other sites
BlindBrick 0 #8 May 24, 2004 I've tried a lot of different manufactuers and the response in general was that they didn't make HP canopies that big. I have zero asperations to swoop and fly my landings very conservatively; however, I do want to be able to do some very agressive canopy manuevers above 3 grand. Given my weight, experience, tempatures, and altitudes I expect to be landing at(5,000 msl+) I am thinking a fully elliptical loaded at about 1.0-1.15 which would put the canopy at 270-280 sf. Airlocks would also be really nice as I am intimately familar with just how suspectible canopies that large are to turbulent air. -Blind"If you end up in an alligator's jaws, naked, you probably did something to deserve it." Quote Share this post Link to post Share on other sites
skydiver30960 0 #9 May 24, 2004 Post edited because I really overcomplicated things... PD makes the Sabre2 up to 260 sqft. It's a bit smaller than you wanted, and not fully elliptical. BUT, the combination of those two things may sort of cancel out. The wingloading will be a bit higher so you'll get a bit zippier performance, but with just a semi-elliptical the openings will be more predictable and if, on landing, you ever feel like you need to shut it down and make it behave you'll be able to do so. I've also jumped with a guy who had a Triathlon 260. So the bigger canopies are definitely out there... Elvisio "gotta go to the dentist" Rodriguez Quote Share this post Link to post Share on other sites
BBKid 0 #10 May 24, 2004 Icarus will make ANY canopy size you ask for (within reason I assume), and I'm sure they'd be able to make a 280sqft Safire2/Omni if you asked. It might cost a bit more than an off the shelf Sabre2 260 - if they are common enough to be described as off the shelf - but better than making your own by far. The other alternative to consider is to lose some weight. I'm not making any judgment about what makes up your body weight, but in some instances it's a viable option. Edit to include link. Nick --------------------------- "I've pierced my foot on a spike!!!" Quote Share this post Link to post Share on other sites
BlindBrick 0 #11 May 24, 2004 Quote The other alternative to consider is to lose some weight. I'm not making any judgment about what makes up your body weight, but in some instances it's a viable option. Yeah, but since I am nearing 200 mph belly flying(I can outfall most of the headsdowners at my old DZ) I wanted to keep my weight and learn headsdown to see if I could break 300. That's actually semi-serious, but totally serious, I deal with stress two ways, I jump or I eat. Since I am currently not jumping, I am eating. It's a kind of Catch-22 situation. I need to lose weight to jump but I need to jump to lose weight. -Blind"If you end up in an alligator's jaws, naked, you probably did something to deserve it." Quote Share this post Link to post Share on other sites
skymedic 0 #12 May 25, 2004 QuoteYeah, but since I am nearing 200 mph belly flying(I can outfall most of the headsdowners at my old DZ) I wanted to keep my weight and learn headsdown to see if I could break 300. do you know what would happen to your poor body if you had a 300mph premature???.....ouch....keep that in mind in a semi serious sort of way.... Marc otherwise known as Mr.Fallinwoman.... Quote Share this post Link to post Share on other sites
BlindBrick 0 #13 May 25, 2004 Quotedo you know what would happen to your poor body if you had a 300mph premature???.....ouch....keep that in mind in a semi serious sort of way.... Actually I hav, and that's why i am not oging to be doing any heads down until i get me new free-fly friendly container this summer. I know that won't totally eliminate the risk, but it should go a long ways towards lowering it. -Blind"If you end up in an alligator's jaws, naked, you probably did something to deserve it." Quote Share this post Link to post Share on other sites
skymedic 0 #14 May 25, 2004 sounds like a smart plan....coaching is your friend when it comes to playing in the inverted world.... Marc otherwise known as Mr.Fallinwoman.... Quote Share this post Link to post Share on other sites
riggerrob 562 #15 May 25, 2004 Take it from some one who has sewn together a couple of kit canopies and read dozens of articles on canopy design: hit up the major manufacturers. Icarus promises to build any size of canopy you want, so ask them to sew together an Safire 270. You might also want to ask Performance Designs about a larger Silhouette. One of our B certificate jumpers is well over 200 pounds and quite happy with his Silhouette 230. Canadian Search and Rescue Technicians fly quite nicely with their Silhouette 300 canopies. Mind you, they jump with far more rucksacks, rifles, snowshoes and medical equipment than you are ever likely to need. Quote Share this post Link to post Share on other sites
BlindBrick 0 #16 May 25, 2004 I called up my old DZO and he's getting me a quote on a 270 sf Safire 2. I've also PM a Jump Shack guy about a quote for a Firebolt 270. What are your opinions on these two canopies? -Blind"If you end up in an alligator's jaws, naked, you probably did something to deserve it." Quote Share this post Link to post Share on other sites
