hackish 8 #1 February 5, 2009 I subscribe to a mag called Nuts and Volts. This month they had an article on how to reef a parachute for a model rocket. They tied the hem shut with a piece of spectra and built a circuit to cut it with a piece of nicrome wire at a pre-set altitude. They defined reefing as choking it off at high altitudes for a gradual deceleration so they could fully open at a lower altitude. I'm not so confident about their definition as I've always felt that reefing referred to the opening. I also think their task would be better suited to a drogue... However, I was wondering how the older rounds were typically reefed from a terminal deployment and what sort of system worked the best? -Michael Quote Share this post Link to post Share on other sites
wmw999 2,122 #2 February 5, 2009 Rounds were slowed by using sleeves and bags; deployment devices to stage the opening. The one round that had something additional was the Starlite, which had a spider slider to further slow the deployment. Wendy W.There is nothing more dangerous than breaking a basic safety rule and getting away with it. It removes fear of the consequences and builds false confidence. (tbrown) Quote Share this post Link to post Share on other sites
peek 20 #3 February 5, 2009 QuoteI subscribe to a mag called Nuts and Volts. I knew there was something wrong with you Michael! Not only are you skydiver, but you have mechanical and electronics thought running through your head too. I have been following his articles. He really puts a lot of effort into the parachute part of his project. I'm impressed. QuoteThis month they had an article on how to reef a parachute for a model rocket. They tied the hem shut with a piece of spectra and built a circuit to cut it with a piece of nicrome wire at a pre-set altitude. They defined reefing as choking it off at high altitudes for a gradual deceleration so they could fully open at a lower altitude. I'm not so confident about their definition as I've always felt that reefing referred to the opening. I also think their task would be better suited to a drogue... However, I was wondering how the older rounds were typically reefed from a terminal deployment and what sort of system worked the best? Pyrotechnic cutters are common. They make them with whatever delay you want. When you pull their firing pin as the load is pushed out the aircraft, it starts a timed burning, and at the end it fires a cutter like in an AAD. Reliable but expensive. I think several hundred dollars. At Yuma Proving Grounds I saw a nichrome wire type of cutter, but I don't think they are common. I don't know what it was based on and don't remember who made it. I was thinking of making a similar one controlled by the usual microcontroller and pressure sensor circuitry, but the pyro cutter is just so common and reliable I don't think it would be worth it. Quote Share this post Link to post Share on other sites
councilman24 36 #4 February 5, 2009 All of the following is based on a 15 year old memory of a NASA tour..... The Space Shuttle solid rocket bosters are recovered with parachutes. A PC that deploys a drogue which in turn deploys the mains. The mains are reefed and use pyrotechnic driven knife cutters to unreef. I have photos of them somewhere. The things are the size of a book. One option would be using a cypres type cutter. Some parachutes other than rounds used lines wraped around the suspension lines to stage the opening. I never saw one in person so someone a little older can chime in. I think the paradactyls used wraps before sliders were invented. Also, look at the packing intructions for a Preserve V from FFE. http://freeflightent.com/PV_Pack_Inst_V.pdf It uses two brake tapes around the lines at the skirt and 7.5" above the skirt. These are 'broken' with an apex line shorter than the canopy radius. So the break at full extension. This helps to stage the deployment for high fall rate openings. Another version is Butlers slider on his rounds. One is hemi-spherical shaped and one is simply a flat circle. A ring on each line and it is just what you would imagine with a slider on a round. I also pack an older Strong pilot rig that has a round with a spider slider. Two pieces of webbing that form an X with a gromment at each end, one for each riser's lines. This actually only goes partially to the skirt and is held short by stopper lines sewn between to suspension lines. So lots of ways to reef/stage round deployments. Along with sleeves and bags mentioned above.I'm old for my age. Terry Urban D-8631 FAA DPRE Quote Share this post Link to post Share on other sites
pchapman 261 #5 February 5, 2009 "Reefing" is a word not really used much in civilian skydiving, even if we do use devices to control, slow, or stage openings. Some really early rounds had no real reefing. They were 'canopy first' - canopy opening, unreefed, no bag or diaper, while the lines were paying out. Malfunction prone, and brutal openings at terminal. Later they went 'lines first' - a bag or sleeve for the canopy while the lines paid out. Sport reserves eventually got diapers of different sorts to hold the mouth closed until lines were paid out. Now there are a few rounds with sliders. (That's a very rough history and it depends on whether one is talking about sport, military bailout, or paratrooper static line.) On military cargo rounds, spaceship recovery, and similar big, heavy, & fast applications, it is common to reef round canopies. I'm not familiar with that territory, but the sequence can involve a lot of steps. E.g., a mortar deployed pilot chute drags out a drogue chute, which after cutters fire, deploys the reefed main parachute which has two stages of cutters firing to allow it to gradually expand to full diameter. Big canopies tend to need more reefing than just a slider. I recall that the huge 7500 ft sq ram air canopies for the X-38 crew return vehicle had a lot of pyro reefing too, that restricted its span initially until allowing it to spread fully. Quote Share this post Link to post Share on other sites
JerryBaumchen 1,048 #6 February 5, 2009 Hi Terry, What is that canopy that uses that spider slider? JerryBaumchen Quote Share this post Link to post Share on other sites
wmw999 2,122 #7 February 5, 2009 The Starlite used one. Wendy W.There is nothing more dangerous than breaking a basic safety rule and getting away with it. It removes fear of the consequences and builds false confidence. (tbrown) Quote Share this post Link to post Share on other sites
likestojump 3 #8 February 5, 2009 Butler has been using a Sombrero slider for awhile now too. and show some pretty intense stuff on their site. http://www.butlerparachutes.com/ also a pretty cool video of a C9 with and without a slider : http://www.butlerparachutes.com/C9/C9slider.wmv Quote Share this post Link to post Share on other sites
airtwardo 6 #9 February 5, 2009 Quote Hi Terry, What is that canopy that uses that spider slider? JerryBaumchen http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=2375625#2375625 ~ If you choke a Smurf, what color does it turn? ~ Quote Share this post Link to post Share on other sites
councilman24 36 #10 February 5, 2009 Jim found it. Must be king of the search engine.Strong made something call an Aerosport a while back. A have the impression it's a little bigger than a 26 but I've never measured them side by side. Has a circumferential vent about 1/4 down from the apex. Panels are completely with only radial seams holding top and bottom together. Packed in a free sleeve, nylon, with lines stowed on the sleeve in the traditional manner. Sleeve is attached to apex with a few inches of velcro. Spider slider is stoped from reaching the skirt about 24 inches (guessing from memory) below. The two locking stows are made on the sleeve and the lines folded to the top of the stows. The spider slider is folded up and stowed in the first rubber band and the rest of the stows made. Cover pulls down. Makes putting it in a Strong seat real easy. I service two of these. Serial #'s in the thirties. I finally took photos of the thing a couple of months ago when I last did one. But they're at home. I've never found another rigger who has seen one, including some of the guys at Strong. I'm old for my age. Terry Urban D-8631 FAA DPRE Quote Share this post Link to post Share on other sites
RiggerLee 61 #11 February 5, 2009 Well the term Reefing was stolen from sailing. It refers to tieing down a section of sail to reduce it's area in high winds. There are lines or ties to squize off a large fold of the sail and keep that section compressed and uninflated. What you're describeing is the clasic use of the word in parachutes. Later it seemed to be applied to all kinds of stageing devices on opening. Just for shits and grins let's see how many we can come up with. 1. I think the first system was where the milatary used a balistic cutter around the mouth of canopies to prevent over inflation till the guy or load had slowed down. As I recall it was a timed charge activated by a pin lower down on the line like a two stow diper. The fuse would start counting when you hit line streatch. I remember seeing a canopy with reefing rings on it once. The small wide rings that look like little sections of tubeing. I think it was a C-9 but the cutter was nolonger installed so I didn't get the chance to see it. I have seen larger ones that cut 1 inch tubeular webbing and they weren't that big. Any one know more? Like what type of rigs they went in? 2. I remember seeing a canopy I think it was one of the pionears with a Runter wrap. A strap locking the base opened by a pin lower on the line. Early version of a diper. I remember Stanford showing me the proper way to pack it by cutting the thing off. 3 Various forms of dipers, two, three stow, full, ashudo. 4. The velcro wrap on the delta two para wing. 5. Pilot chute controled top skin reefing. 6. Pilot chute controled around the skirt reefing. I'm listing this seperat because even though I've never had the chance to jump a Statostar with it I hear this one actualy worked. 7. The tape slider on the Starlite. 8. I've seen the picture in pointers like the rest of you of the hydrolic reefing system on the volplane but I've never gotten my hands on one. 9. PC controled reefing on squares. As I recall it was used all the way up through the Evolution. 10. I'm lumping all the sleaves, pods, and bags into one pile. 11. Modern rounds like the buttler sombraro and BRS. This shit can really work well. I've built some things like this for various purpases. 12. Some really large cargo squares that use multable cutters to stage span wise inflation. 13. At the opposit end I've packed some low altitude ejection seats that had a lanyard on top of the PC attachad to the aircraft to extract the canopy. It was cut a second later by the balistic cutter I mintioned. 14. I've never seen a balistic spreader. Any one ever played with one? 15. Remember the guy that was trying to build rounds and paragliders with inflating presureized tubes to speed opening and hold them out ridged? He ever go any where? Come on what else can we ad to the list? LeeLee [email protected] www.velocitysportswear.com Quote Share this post Link to post Share on other sites
JerryBaumchen 1,048 #12 February 5, 2009 Hi Lee, QuoteI remember Stanford showing me the proper way to pack it by cutting the thing off. I'll 2nd that. I seem to recall someone going in when the pin failed to pull free of the little pocket that it sat in. Anyone else????? JerryBaumchen Quote Share this post Link to post Share on other sites
hackish 8 #13 February 6, 2009 Wow this has turned into a wealth of new knowledge for me. I'm working on my round rating so it's nice to see how it all fits in. Last weekend I packed a baby cobra and it really had no reefing to speak of. The lines were stowed with elastics in the bottom of the belly mount pack tray and I can well imagine it beginning to inflate while it's still unstowing the lines. Ouch. Peek, yes, guilty as charged. I haven't built a rocket in years but was thinking it would be fun to build one with a ram air recovery system... Then I looked at the price of model rocket engines (the big ones). Think I will stick to skydiving. -Michael Quote Share this post Link to post Share on other sites
RiggerLee 61 #14 February 6, 2009 A what? Did you say Baby Cobra? I didn't know any one jumped those things. I thought they were grounded? What's the story? LeeLee [email protected] www.velocitysportswear.com Quote Share this post Link to post Share on other sites
councilman24 36 #15 February 6, 2009 There is a new Korean member of PIA that is making a building emergency parachute that opens using, IIRC, bungee loaded tent poles around the skirt. Saw video of the thing with live test jumps from a crane. We were all wondering if they had one with them to jump in the atrium of the embassy suites. But the reefing system is the container. The only thing holding it closed. I'm old for my age. Terry Urban D-8631 FAA DPRE Quote Share this post Link to post Share on other sites
pchapman 261 #16 February 6, 2009 Quote A what? Did you say Baby Cobra? I didn't know any one jumped those things. I thought they were grounded? What's the story? Hi Lee, They were Canadian made, popular locally in their time. I've got one in my belly mount too.I don't know the details, but they seemed to vary over the years depending on what was current technology -- some were like diaperless 26' Lopo's with 4 line releases, some late ones were much more like Phantoms. But: They were never TSO'd. No problem in Canada. Never grounded that I know of. (Although of course any early mesh better be checked.) So while not grounded for safety reasons, the lack of TSO obviously stops their use by US residents in the US. Quote Share this post Link to post Share on other sites
hackish 8 #17 February 9, 2009 If I recall correctly it was made by a company called Niagara Parachutes or something like that. This is a belly mount and I'm hoping to jump a jumbo PC this year so that will be the reserve considering the entire rig is original. Looking at the actual structure of the reserve it does not seem to have anything in particular that sets it aside from any other round reserve. I'm not extremely particular about the deployment system since it has nothing for staging and the lines are just stowed in the bottom of the deployment bag, but this does not seem that different from others of that era. Under the Canadian Rigging system our round rating is separate from the square rating so I've got to pack 10 of these rounds to get the certification. -Michael Quote Share this post Link to post Share on other sites
stratostar 5 #18 February 9, 2009 Don't put it in upside down then...... I know someone who still has one installed and in a belly wart. They got it from Bill Cole.you can't pay for kids schoolin' with love of skydiving! ~ Airtwardo Quote Share this post Link to post Share on other sites
JerryBaumchen 1,048 #19 February 9, 2009 Hi strato, I've only seen maybe three of them; and that was back in the 70's. As I recall, there is not enough slack to put the pin in upside-down. But with enough effort I'm someone could do it JerryBaumchen Quote Share this post Link to post Share on other sites
stitch 0 #20 February 13, 2009 Choking off the Apex is not reefing. Below is a link to a pdf from Apex Base that will give you all the explanations you want for freepacking a round with or w/o a diaper. And explain to you and others why the apex is choked off. Though it should be obvious. http://www.apexbase.com/store/Manuals/21-26_H2O%20Canopy.pdf"No cookies for you"- GFD "I don't think I like the sound of that" ~ MB65 Don't be a "Racer Hater" Quote Share this post Link to post Share on other sites
riggerrob 558 #21 February 15, 2009 I owned a Baby Cobra from 1979 to 1983, but never had to deploy it. All the Baby Cobras - that I packed - looked like copies of Strong/Security/National/Pioneer 26 foot conicals made of MIL Spec 0 to 30 cfm fabric. Most Baby Cobras had two-bite diapers sewn on. Niagara Parachutes faded from the skydiving scene after founder Eddie Grimm died (in an ultra-light airplane) during the mid 1980s. The last time I visited their shop was about 1989. Quote Share this post Link to post Share on other sites
likestojump 3 #22 July 27, 2014 Just got one. I am betting some of ya'lls would like pics, so this is my good deed for 2014. Quote Share this post Link to post Share on other sites
Dutton 0 #23 July 31, 2014 I packed two of these sleeved Strongs for likestojump a few months back. They were super easy! It is also interesting to note that the C-9 pilot rigs I have packed were deployed Type 1. Wonder how that feels at terminal or more. As far as BASE round packing, I've done the NRG bridge with PH 24's type 3 and type 1, with and without the rubber band. I settled on type 1 with no rubber band and have done 5 seconds no problem. Quote Share this post Link to post Share on other sites
riggerrob 558 #24 July 31, 2014 "Dutton... It is also interesting to note that the C-9 pilot rigs I have packed were deployed Type 1. Wonder how that feels at terminal or more. ..." ................................................................................. Funny! I sewed (Type 4) diapers onto hundreds of C9s when I worked for Butler and Para-Phernalia. It is silly to pack a C9 without a gadget that vastly improves opening reliability while reducing opening shock????? Quote Share this post Link to post Share on other sites
Andy9o8 0 #25 July 31, 2014 Quotebest way to reef a round? For the dyslexic, This is the best way to round a reef. Now back to our show. Quote Share this post Link to post Share on other sites
