Ronaldo

Speaking about newbie swoops here are a couple from last weekend. It was also the first time someone took pictures of my landings. By the way, the photographer is excellent, he does miracles with that camera. The yellow&blue canopy is a friend's Pilot 168 that I jumped for the first time, the other one is my Cobalt 150. Please don't make fun of my home made ff pants Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

During packing I had the impression that Icarus canopies present more slack near the bridle attachment point (maybe the ring is positioned in a slightly different area). It could be just me but I was never able to pull the bridle attachment as far as shown in the picture. Blue skies! Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

I used to psychopack a lot and I noticed that for larger canopies the extension really helps. On a larger canopy the bridle would have to run a long path from the center of the roll to the link thus making it very difficult to bag the canopy. For smaller canopies it is not so necessary (but helps). Be careful with the length of the extension specially if someday you (or someone else) PRO pack the canopy. An extension that is too long may wrap part of the tail when bagging, causing damage on opening. Safe skies Ronaldo Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

Hi Rob, Thanks for clarifying the license issue. The FAA equivalent in Brazil is ANAC (previously DAC). Similarly to what you described about Canada and Russia, ANAC have absolutely no involvement with parachute equipment but only with issues regarding parachuting operations (licensing aircrafts, pilots and air space (NOTAMs). We don’t have any kind of rigger course or certification except for the military (they have their own rules). As a fact, FAA’s riggers licenses are accepted by our local regulations. I totally understand your point about Standards. My wife and I have been involved with the aviation industry for a while. We both know how complicate and incompatible regulations can be. I don't think we'll ever have a world regulation for sport parachuting (we still don't have one for aviation). Safe skies! Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

I’ve traveled to US a couple of times but mostly on business so I did not have a chance to jump. We have our own skydiving organization here; it is called CBPq. Up to now my reserve is being packed by a guy who is just listed at their web site as a “reserve packer”. He is the one that signs my data card. I understand your concerns when I say that I re-close the container, that’s why I’ll learn how to pack and thus sign my own card. The majority of the reserve packers listed are not USPA licensed riggers. If I want my reserve repacked by a rigger I’d have to ship it to another state. According to current regulations a reserve parachute must be packed by a CBPq registered packer or rigger (previously you just needed a C license to do it). When I start packing my reserve I will definitely fill an application form to make it legal. I’m not that good as you mentioned, I just feel the need to know as much as I can about that piece of webbing and fabric that saves life at weekends. As I said before, it may be easier to trust a rigger if you live in US, but I just don’t feel I can do it blindly here. The careless attitude I see here from many jumpers is what really worries me. To pass a rigging course I’m pretty sure I’ll have to study a lot.

Sometimes I think I’m the only one who does not trust my life to anyone but me. It really amazes me when I hear my friends say that they have never seen the color of their own reserves. Most of them have never read their rig’s owner’s manual. Some others can’t even pack their mains. How far can you trust your rigger (or packer)? Maybe in US you can blind trust your rigger because almost everything written is in English but this is not the case here in Brazil. We have very few USPA licensed riggers, the majority of reserve repacks here are done by more experienced skydivers (some of them not so experienced). Most of these guys can’t even read a manual in English! How should I expect them to correctly assemble and pack my reserve? I was the first to get a Wings at my DZ. Even giving a printed manual my reserve container was incorrectly closed. I had to translate the manual but I still open the container after repack simply because I know I will close it better (I always get better PC launches when I close it). I do my own assembling and inspection (main and reserve), check line continuity, install and remove links, sliders, check line trim, change brake lines, I even make small repairs. My next reserve repack will be probably done by me. I’m not saying that everyone should start messing with their own equipment but I just feel that knowing a little bit about it does really good to your peace of mind. Maybe it’s just engineer paranoia . Blue skies Ronaldo Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

I do remember reading a post about this but it could have been written by someone else. If he really said that then I can stop my monthly maintenance with no worries. Blue skies! Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

Actually I think he said that rotating the rings is useless and does nothing to improve releasing. It serves only to move oil and dirty from your hands to the webbing. Bending and flexing is what really improves the mechanism. I guess washing the risers helps too. Safe skies! Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

Did you check brake line length on both canopies while in the air? Many people just switch canopies without paying attention to this which obviously leads to an unfair comparison. Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

No manufacturer will take responsibility if any part of the system fails, why would a packer do? Parachute openings are chaotic events, even if everything looks perfect on the ground, things can still go wrong in the air. When you get a bad opening from a packer, the only thing you can do is tell the guy and point obvious mistakes (if they are obvious). My Cobalt has 7 small patches on the trailing edge due to a packer not stowing the bridle extension correctly when putting the canopy into the bag. I did not blame him; after all I put the extension because I was psycho packing the canopy. Yes, he could have paid more attention, but I traded the reliability of my own packing to get extra minutes for debriefing my coached jumps. In the end the best option is to pack for yourself. If you must use a packer, at least set your brakes, uncollapse slider and PC and check bridle routing and container closure. Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

I do agree that line stows create bag whip, specially because they are not all placed in the same plane as the bridle but IMO bag inertia and pilot chute speed play a very important role in not giving the bag much chance to rotate. I think that it would take hundreds of jumps with controlled packing and deployment to show at least a measurable difference in line twists with or without stows. Besides that, any advantages of free stowing might be overcome by the potential for packing error (tension knots, for example). I also would expect free stows to be more effective on smaller (lighter) canopies as they would be more sensitive to bag whip. IMHO line twists are caused by the way the bag leaves the container (caught by a flap or a corner or having the last stow too close to the links). I’m only considering bag twists, not twists during inflation, which are usually caused by body position. BTW, I don't have much skydiving experience so please take all this as an engineer's opinion Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

Get the linespecs from Aerodyne and have someone to help you check the lineset. The best option is always to contact the manufacturer first but here are some ideas: You may try to pull on rear risers slightly to speed up the inflation. Do it slowly and evenly to avoid line twists. I'm not sure if it is a good advice at 45 jumps so someone please correct me if I'm wrong. I guess another option is to cut a small hole on the slider (your rigger can do it). Start with a very small one and increase diameter until you reach the perfect opening for you. It is important to pack the same way while making these test jumps. Good luck Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

Cool, I have a few more questions if you don't mind: Did you have any particular reason for making this modified bag? Was it to speed up packing, reduce line twists or just to prove everybody that line stows have little or no influence on the openings. Also, what were your impressions through all these jumps (cleaner and faster deployments, lower incidence of line twists or no change at all)? Have you ever tried some kind of tuck tab design? BTW, nice sewing job! Safe skies! Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

Did you notice any wear caused by the Velcro? Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

Hi Billy, I think it is not a matter of which material is better but which one suits you and your canopy better. Generally speaking the most common options are: Microline – lasts longer, has low bulk and low drag but changes dimensions considerably and does not absorb the shock (such as in a hard opening); Dacron – can absorb part of the shock in a hard opening which may save your neck (I have no idea of how it changes trim as you jump), increases pack volume and drag; Vectran – stay in trim for the lifespan of the lineset, has low bulk and low drag but does not absorb shock and has a shorter lifespan than Microline. Your best bet should be stay with the original material according to manufacturer specs. They have designed the canopy taking the material properties in consideration so it is most certainly appropriate. Personally I prefer Vectran because I like the idea of keeping the performance and opening characteristics unchanged through the life of the canopy. If you decide to change materials, make sure they are compatible with your system. For example, some manufacturers use a modified trim chart for Microline that includes some “errors” to compensate for line shrinkage and/or elongation. This way the canopy reaches the perfect trim only after a certain number of jumps. If you decide to build a lineset with Vectran based on this chart you’ll get a canopy that is out of the ideal trim from first to the last jump. Vectran requires also stainless steel grommets for the slider as it is extremely abrasive to brass. I think you can get Dacron at least in red and white but I’m almost sure there are no color options for Microline and Vectran. BTW, I’m neither a rigger nor experienced skydiver, just a mechanical engineer who tries to understand as much as possible about gear by reading a lot. There are a lot of very experienced people here that can add a lot more and correct any misinformation that I may have said. Hope it helps Blue skies! Ronaldo Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

Call Roy Torgeirson at Rigs&Things Paraservice. Kick ass dealer, has helped me a lot (I'm in Brazil) and will sure help you. Toll Free # 1-877-TOP-RIGS Phone: 1-863-675-4628 Edit: I forgot the e-mail: [email protected] Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

Another good reason I see to do this test is the opportunity to adjust brake line length to get the maximum flare. It would help a lot in a real emergency situation. I think I'll do this test jump! I have the perfect plane and DZ for it. It's a big farm on the countryside with a very nice runway and a few ultralight aircrafts that I often jump from. (including a friend's trike which I like a lot). It is a very large and safe place with plenty of space and no traffic. Is there any problem to the reserve besides depreciation of resale value (i.e. increase porosity)? Safe skies! Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

I used to think about this all the time when I had a Tempo. Now I have a PDR which makes me a little bit more comfortable, but I still haven't give up on the idea. I think not having a bridle attachment on the canopy is the major issue now. Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

Hi Mark, I don’t have much experience but I really don’t think that a 7 cell canopy loaded at less than 1.0lbs/sqft would be so sensitive to harness input (as you mentioned, you almost had to pull one toggle down to your waist). The first thing you can do is check the lineset regarding symmetry (all lines, including brakes). If the lineset is OK then you definitely have a problem on the fabric (panels cut or sewn wrong, reinforcement tape shrinkage, etc). I’ve seen 2 canopies with built in turns (one was mine), both new generation models. No matter how precise the laser cutting gets, a human being still sews everything so mistakes will always happen. I guess better tools, training and quality control are helping reduce these mistakes on newer designs. BTW, what just happened to you was the main reason I switched my Tempo for a PDR. Tempos seem to have a history of built-in turns. I still would feel much more comfortable if I had the opportunity to jump it as a main. Congratulations for performing your EPs well. I wish you a quick recovery. Blue skies! Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

I was also curious so I did a quick test rubbing a piece of Vectran line against a brass grommet to see if there was really a possibility of damage. It took only a few seconds to see the marks inside the grommet. Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

Thanks Mel, you’re right, I need ss grommets because I may reline my Cobalt with Vectran in a near future. I just did an h-mod on it to fix some opening issues, so far it seems to be working well but I still have an Xfire on the closet in case I get another slammer. Although I can have access to a large press and die set I’m starting to think it would be much simpler to order one. BTW, could you install these grommets for me? Is it possible to replace the original ones instead of making a new slider? Safe skies Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

Good idea, I guess canopy manufacturers will be the best option. BTW, thanks for the DJ & Associates link. I didn't know that one, very good source of supplies. Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

Tried that, but it seems like they have only small dia grommets. Shipping is not a problem, I've bought from Para-gear a couple of times. Customs is the real problem Thanks Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

Hi, Does anybody know where I can order stainless steel slider grommets (small quantity)? Safe skies Ronaldo Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted

If you get the line specs, please let me know who gave you. I had a Xfire149 that needed a new line set (Vectran not HMA). I tried as much as I could to get the line trim chart without sucess. Engineering Law #5: The most vital dimension on any plan drawing stands the most chance of being omitted