leroydb 0 #1 November 11, 2003 Idea: Been thinking... I know that's dangerous... Could you make a multiple point attachment d-bag for bird man jumps? I have seen it used on base canopies, why not a d-bag? I am sure someone has probally already thought of this but I am curious to why is a multi -point d-bad used?Leroy ..I knew I was an unwanted baby when I saw my bath toys were a toaster and a radio... Quote Share this post Link to post Share on other sites
TomAiello 25 #2 November 11, 2003 What would the advantage be?-- Tom Aiello [email protected] SnakeRiverBASE.com Quote Share this post Link to post Share on other sites
leroydb 0 #3 November 11, 2003 I am not sure... thats why i am posing the question I am thinking that it "MIGHT" promote a more on heading deployment, less chance for a spinning mal???Leroy ..I knew I was an unwanted baby when I saw my bath toys were a toaster and a radio... Quote Share this post Link to post Share on other sites
TomAiello 25 #4 November 11, 2003 To cross-post my response to your crosspost... I believe the Multiple Bridle Attachment (multi) was intended to: a) reduce center cell strip Center cell strip is caused by the extraction force "ripping" the center cell out of the freepacked canopy before (or while) the rest of the canopy is extracted from the container. This problem does not occur on canopies packed in bags, since the bag keeps the canopy contained, along with it's center cell. b) reduce tail slump The weight of the lines in the tail pocket causes the tail of the freepacked BASE canopy to "slump" during extraction. This can lead to tail inversion. It also makes the pack job assymetric during inflation. A canopy packed in a bag does not have any additional weight on the tail (because the lines are on the outside of the bag), and holds the tail in place until line stretch anyway. Neither of the two problems that the multi is intended to address occur on bagged canopies. What advantages do you see for using a multi with a deployment bag system?-- Tom Aiello [email protected] SnakeRiverBASE.com Quote Share this post Link to post Share on other sites
TomAiello 25 #5 November 11, 2003 QuoteI am thinking that it "MIGHT" promote a more on heading deployment... The multi is not intended (except incidentally, as the result of getting a neater pack job to line stretch) to improve opening heading. In fact, some very experienced BASE jumpers (including, interestingly enough, some leading BASE wingsuit pilots) have removed the multi from their canopies because they were concerned that it actually degraded opening heading. Quote...less chance for a spinning mal? I'm not sure that it would help, and the consequences of a spinner with a multi could potentially be even worse than without (since the multi would have some potential to spin up and entangle or compress the topskin of the canopy). Don't most spinning malfunctions occur as a result of the bag spinning on the way to line stretch? I'm not overly educated on skydiving, so someone correct me here if I'm wrong. But, if the mal results from the bag spinning prior to canopy extraction, then the hypothetical "multi-bag" would have no effect, because the spinning would take place before the multi was deployed (hence before it could have any possible stabilizing influence on the canopy).-- Tom Aiello [email protected] SnakeRiverBASE.com Quote Share this post Link to post Share on other sites
leroydb 0 #6 November 11, 2003 This is why I was posting the question... to find out if it would help or harm..... see now I wont go and kill myself wuite jsut yet, thanksLeroy ..I knew I was an unwanted baby when I saw my bath toys were a toaster and a radio... Quote Share this post Link to post Share on other sites
TazDevil 0 #7 November 12, 2003 Something of this nature is already being done. I believe that Henry at Wings was the first on the idea. It is not a multi attachment but simply a yolk (similar to the reserve d-bag of most manufacturers) Basically, take a triangle piece of material and sew one side all the way across the bottom of the d-bag and then you end up with a point of the triangle approx. 6-12" toward the pilot and connect that point of the triangle to the bridle. I think it helps bring the bag out of the tray cleaner (I don't have cut away corners on the rig) and possibly gives stability while lines are paying out. I have over 100 BM jumps on a stabilized bag.... no complaints Quote Share this post Link to post Share on other sites
TomAiello 25 #8 November 12, 2003 So the idea is to stabilize the bag while it travels to line stretch?-- Tom Aiello [email protected] SnakeRiverBASE.com Quote Share this post Link to post Share on other sites
leroydb 0 #9 November 12, 2003 yea... maybe if it had more material? like a tirangle? i think it would help deployment...Leroy ..I knew I was an unwanted baby when I saw my bath toys were a toaster and a radio... Quote Share this post Link to post Share on other sites
diablopilot 2 #10 November 12, 2003 I think the idea is to pull it out of the pack tray with equal tension across it's width, rather than from a center point as a traditional bridle does. It's not so much an aerodynamics thing, more of a don't let one side of the bag hang up in the tray, thus imparting a twisting or spining motion to the bag.---------------------------------------------- You're not as good as you think you are. Seriously. Quote Share this post Link to post Share on other sites
jmfreefly 0 #11 November 13, 2003 Yep, I got one of these with my new wings. It was impossible for me to understand what the heck it looked like or how it worked (even when sent a pic of just the bag from SRI). I finally just emailed Jari, and he said "Yeah, it works", so I got it. After seeing the finished product, it makes sense on why I didn't understand before -- the triangle is sewn to the bridle. I have put about 50 or so jumps on the bag, and my seat of the pants feeling is that it does help somewhat.. maybe '30%' less off heading openings.. It does make packing a little wierd at first, as you have this extra material to deal with while closing. The fact that it is sewn to the PC kind of sucks.. but ah well. I guess when the PC dies, I can just pick the stitching and re-stitch. Maybe I will try to take a pic .. Quote Share this post Link to post Share on other sites
jmfreefly 0 #12 December 12, 2003 With the help of Kevin922, here are pics of the dbag. Some may be a little dark/low contrast, but hopefully it makes sense. The pics are here: http://www.interone.net/gallery/view_album.php?set_albumName=album03 (Scroll to the bottom) Eventually he is going to clean them up and put them on his site: www.flybirdman.com Hope that helps. Quote Share this post Link to post Share on other sites
