pchapman 278 #1 January 14, 2003 Here's a question perhaps best answered by those who were active jumpers in the waning days of round reserves. It has long been said that round canopies manlfunction more often than squares. But I think much of that is based on knowledge of the old days of main and reserve rounds that didn't use diapers (or, for troop parachutes, before mesh anti-inversion netting). (a) Anyone have an idea how round reserves with diapers fare for opening reliability? I'm just guessing that their effective reliability is no worse than squares, and even perhaps a bit better because some types of malfunctions with them are more controllable & survivable. (b) When did round reserves start getting diapers? From reading old adverts and the Poynter manuals, it seems like at one time (early 80s?) a lot of emphasis was made on making round reserves as lightweight as possible. E.g., some certifications in the Low Speed category, National Phantoms before the days of the added kevlar bands, stories about the Pioneer TriCon (don't know what the issue was, but it was downgraded from Standard to Low Speed category) (c) Just how much of a problem were these light weight reserves, as far as resulting in reserve damage during rogue openings at terminal velocity? It would be interesting to read USPA accident reports from those days. Blowing a gore or two is still quite survivable, but if the lower lateral band blows, even with other lateral bands up top, I guess it's usually game over. Quote Share this post Link to post Share on other sites
wmw999 2,334 #2 January 14, 2003 No numbers, but anecdotal information (i.e. I jumped a lot of rounds). Numbers on reserve malfunctions are going to be hard to find, simply because the sample size is so small. I don't ever remember actually seeing a round reserve malfunction, in about 6-7 years of very active jumping, over about a 10-year period. Square reserves began to be a factor only in the last couple of years before I laid off. The only round reserve I remember that was packed without a diaper or bag of some sort was the military surplus round. They could open hard. Diapers improved chances of avoiding a lineover or inversion by having the canopy not inflate until the lines had some tension on them. I don't remember packing any round reserves with anything but a diaper or nothing on them; no bags or sleeves. I don't know about earlier (pre 1977 or so) sport rounds. I don't remember ever hearing more than third-hand about a reserve blowing up. But I know that a couple did, simply because there aren't that many third hands. In about 500 round jumps, I had 2 cutaways that were due to canopy malfunctions. I also have a 20-ft diameter round reserve. It packs quite small. I'm sure there are people out there who have all of the old Parachutist magazines with accident reports as far back as they went. 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
Kirils 1 #3 January 15, 2003 I jumped a round main and reserve until 1972, and had a round reserve till 1985. I think the current square reserves and their deployment systems are far superior. How many of you have had to deploy a bellywart reserve and had to pull it back in, throw and shake it to get it to open? Most of you under the age of 50 don't know how good you have it."Slow down! You are too young to be moving that fast!" Old Man Crawfish Quote Share this post Link to post Share on other sites
jbrasher 1 #4 January 15, 2003 a. beter than w/o, usually. b. around the early 8's sounds fine but I wounldn't put it past the Germans circa 1930-40's to have done it first. c. I've seen/heard of several that had problems, usually due to gross overloading or tumbling during deployment. I have also seen several rounds with blown gores landed and survived. Red, White and Blue Skies, John T. Brasher D-5166 Quote Share this post Link to post Share on other sites
steve1 5 #5 January 15, 2003 I quit packing reserves in about 1975. I don't think they had diapers until after that date. At least I never heard of them. Out of about 300 para-commander jumps, I had two malfunctions. I think both were caused by having too short of a retainer line which caused my chute to deploy with the sleeve tangled in some modification holes. I also made about 50 army static-line jumps on rounds. I did see a few May-West type malfunctions, by other jumpers, but had good openings on every military jump I made. I have no doubt rounds do malfunction more often than today's square canopies. It's amazing to hear of people with thousands of jumps who have never had a mally. I know very little about the anti-inversion netting they use today in the military. It might help a lot. When I first started jumping in the army, most reserves didn't have pilot chutes. You were trained, in the event of a spinning malfunction to throw your reserve out in the direction of the spin. A friend of mine was jumping with the Canadian Army, on a training exercise, when he had a line over malfunction. He did as he was trained and threw his reserve out in the direction of the spin. The only trouble was, it started up inside his main. So he had to pull it back in and try to throw it out again. About this time he hit the ground. Luckily he was a tough old bird and it didn't hurt him much. At least he was able to party down with everyone that night, and after a few beers felt great. Aren't you glad you didn't jump back then? Steve1 Quote Share this post Link to post Share on other sites
murrays 0 #6 January 15, 2003 QuoteFrom reading old adverts and the Poynter manuals, it seems like at one time (early 80s?) a lot of emphasis was made on making round reserves as lightweight as possible. E.g., some certifications in the Low Speed category, National Phantoms before the days of the added kevlar bands, stories about the Pioneer TriCon (don't know what the issue was, but it was downgraded from Standard to Low Speed category) (c) Just how much of a problem were these light weight reserves, as far as resulting in reserve damage during rogue openings at terminal velocity? Several years ago...17 maybe? I saw a National Phantom 28 being examined by CSPA's technical Director at the time, Duncan Grant. This was one of the reserves without the kevlar reinforcing bands...and likely one of the reasons they added the bands. The reserve had been deployed by a student at Morden, Manitoba. One of the grommets on the diaper wasn't properly seated and it somehow grabbed the canopy and started tearing it. The tear went from the lower lateral band to the apex...you could literally drive a truck through it. I started jumping at Morden some time after I saw this parachute and the guy jumping it was very lucky to have survived. Apparently, the reserve was streamering, everybody on the ground thought he was toast, then it inflated when he was just off the deck and then collapsed. Had it inflated momentarily higher he likely would have died, according to the description I heard. My first reserve, a 26' Navy Conical that still had the sea pockets on it didn't have a diaper. I used it on my first reserve ride. Cutaway from a crw wrap. I remember a sound almost like a rifle "crack" when it opened but I don't remember it as being a hard opening even though it was fast. Saved my life but I bought a new set of gear with a square reserve the next year. I've never jumped a round since.I am certain that people had more reserve rides when jumping rounds. Tom McCathy from Gananoque had I don't know how many reserve rides in his first 2000 round jumps and then went several thousand when he started jumping squares. He had a complete inversion on a round reserve once. he told me he opened his reserve, checked it...something seemed wrong but he couldn't figure out what it was in his adrenaline charged state. Then, when he picked up his reserve he realized that his reserve pilot chute was inside the canopy and not outside. His reserve had turned itself completely inside out! What had looked odd was the pilot chute dangling from the apex inside the canopy...it just hadn't registered.-- Murray "No tyranny is so irksome as petty tyranny: the officious demands of policemen, government clerks, and electromechanical gadgets." - Edward Abbey Quote Share this post Link to post Share on other sites
fergs 0 #7 January 15, 2003 I packed many non-diapered and diapered round reserves from early 70's to early 80's. Some were with a pilot chute, others without. Many were front mounted reserves, others piggy back systems. Some were used in anger - all worked. I've had 3 reserve rides in last 30 years - all on round reserves. The first was an intentional cutuway with one-shot capewells and a front mounted 17' GQ reserve. That was 1973 or 74. Then a cutuway from a brand new (its' very first jump) strato-cloud in 1978 or so. That was a piggy back system, R-2 release (the old capewell fittings retrofitted with a combo leverage and velcro tape), navy conical 26' non diapered reserve. Finally, in 1981 a cutaway from a total (well, not exactly a total .... a pull-out deployment where my old bow-line knot on the bridle simply came undone - it was a real "throw-away" pilot chute .... I literally threw it away, hahahaha). SOS system made the decision to cutaway or not cutaway easy. It was a 26' PISA conical reserve, also non diapered. Haven't had a mal since then, which I put down to sloppy and fast pack jobs - but touch wood, I do expect a malfunction sometime in this millenium, hahahaha. Jumped rounds in early 70's before going to three cornered contraptions, then squares, with my first ring-and-rope strato star in 1976. Also dispatched many students on free-fall and static lined round canopies. Occasionally they malfunctioned - mostly line overs. Malfunction rate on round canopies was probably greater than we now see on square canopies, but cannot back up that belief with cold hard facts and figures. But I never saw a round reserve have any problems. Interested to hear of other oldies experiences. Blue Skies, fergs Quote Share this post Link to post Share on other sites
billvon 2,772 #8 January 15, 2003 I think that, at a very basic level, rounds are more reliable than squares. However, the deployment systems used on rounds are not as reliable, mainly because they're older. A true test - take a modern square reserve and put it up against a round with a modern reserve PC, a free sleeve, and anti-inversion netting. I'd be willing to bet you'd see better reliability from the round. Quote Share this post Link to post Share on other sites
riggerrob 613 #9 January 15, 2003 billvon, The only way your theory is going to work is if you use the latest generation of rounds with sliders (BRS or Butler BAT series). Unfortunately none of those are certified as man-capable reserves. Quote Share this post Link to post Share on other sites
billvon 2,772 #10 January 15, 2003 >Unfortunately none of those are certified as man-capable reserves. Yep, and they probably never will be. No point. Quote Share this post Link to post Share on other sites
riggerrob 613 #11 January 16, 2003 billvon, Rounds are less reliable because they take longer to fill. Rounds open in a "snivel, snivel, snap" sequence and it is very difficult to predict how long they will snivel. If you remember Poynter's Manual, rounds have very little spreading force at the skirt so it flops around for a while before sorting itself out. Sometimes some of the skirt blows across and starts to inflate on the outside of the skirt on the far side. This is the first step in a classic line-over, Mae West. I may have only done 70 jumps on rounds, but two of them included line-overs. I may have landed both canopies safely, but they had so many dozen small holes that they were promptly scrapped. Back to round opening sequence. Once the skirt has decided to open, then air rushs to the apex, where it starts to back up and the canopy inflates from the top down. Round canopies often "over inflate" and sometimes they get confused during the rebound. The whole inflation process on a round parachute is long, complicated and difficult to predict. A variety of inventions (taschengurts, spreader guns and Webb chutes) can help spread the skirt, but they have never been available on skydiving gear. Ram-airs on the other hand have simple inflation characteristics. Basically you expose the bottom skin to the wind and it inflates. Cell inflation is a secondary consideration. Quote Share this post Link to post Share on other sites
billvon 2,772 #12 January 16, 2003 >Sometimes some of the skirt blows across and starts to inflate on > the outside of the skirt on the far side. This is the first step in a > classic line-over, Mae West. Anti-inversion netting makes the odds of this drastically lower. >Round canopies often "over inflate" and sometimes they get > confused during the rebound. Not as big an issue if they have sliders. >Ram-airs on the other hand have simple inflation characteristics. > Basically you expose the bottom skin to the wind and it inflates. Cell > inflation is a secondary consideration. Unfortunately, simple inflation is not sufficient to make a ram air canopy fly; it needs both cell inflation and airspeed to land safely, and several mals (like lineovers) do not allow it to fly in a survivable manner to the ground. If you do find yourself with a reserve lineover, which type of canopy do you hope it is? Quote Share this post Link to post Share on other sites
relyon 0 #13 January 16, 2003 QuoteIf you do find yourself with a reserve lineover, which type of canopy do you hope it is? I hope I never have a reserve lineover, regardless of what the reserve is. If I have on I'll attempt to find the line and cut it. If I don't, you'll be reading about it in Incidents. Bob Quote Share this post Link to post Share on other sites
brettpobastad 0 #14 April 6, 2003 RR Your wrong about ram-air canopies opening more orderly and quicker than round canopies. What data do you have on this subject? PS I've never heard of a canopy getting 'confused' while opening. Quote Share this post Link to post Share on other sites
mikeat10500 12 #15 April 6, 2003 Parachutes are round. The ram air inflated wing is a toy for swooping or CRW. If you want to slow down a 300mph+ dragster you use an aerodynamic decelerator...and they are round. If you want to lift a 10lb bag off your back you use a pilot chute. Ok lets get out our pilot chutes, wave them around until inflated and check what shape they are. You see...you rely on a round parachute to open your square every time. If someone put a square in where you reserve goes than you have to mains. .......mike ----------------------------------- Mike Wheadon B-3715,HEMP#1 Higher Expectations for Modern Parachutists. Quote Share this post Link to post Share on other sites
mikeat10500 12 #16 April 6, 2003 You will find opening times for my reserve on pg36 of Para Gear #67. 1.1 to 2.5 seconds. Why don't all reserve manufacturers advertise opening times? ...mike ----------------------------------- Mike Wheadon B-3715,HEMP#1 Higher Expectations for Modern Parachutists. Quote Share this post Link to post Share on other sites
riggerrob 613 #17 April 6, 2003 If you don't believe what I have to say about round parachutes getting "confused" during opening, refer to Manley Butler's paper on development of his HX series of round parachutes. http://www.butlerparachutes.com/ I have suffered two inversion type malfunctions on round parachutes (out of 70 jumps on rounds) and two line-overs on ram-air canopies (out of almost 4,000 on squares). Pretty poor odds if you ask me! Both the round canopies were packed by military riggers (Canadian Army and West German Army) and I packed both line-overs on the squares. I will freely admit that I packed the squares in a sloppy manner. Quote Share this post Link to post Share on other sites
Hooknswoop 19 #18 April 6, 2003 Quote You will find opening times for my reserve on pg36 of Para Gear #67. 1.1 to 2.5 seconds. And it also lists the Turn Rate (LOL), Forward Speed (LOL!) and Rate of Descent (OUCH!). In BASE jumping, rounds are known for unpredictable opening speeds. Don't pull low w/ a round on a BASE jump. I have 14 reserve rides on squares, all stand-up landings, on the spot I chose. Hook Quote Share this post Link to post Share on other sites
mikeat10500 12 #19 April 6, 2003 QuoteIf you don't believe what I have to say about round parachutes getting "confused" during opening Oh I believe ya Rob...I had a look through Dan Pointer's manuals once. Quote I have suffered two inversion type malfunctions on round parachutes (out of 70 jumps on rounds) and two line-overs on ram-air canopies (out of almost 4,000 on squares). Pretty poor odds if you ask me! Both the round canopies were packed by military riggers (Canadian Army and West German Army) Well that explains the mals...I demand a retest!!! Quote and I packed both line-overs on the squares. I will freely admit that I packed the squares in a sloppy manner. Yes this is why I jump a square main. You can pack it half drunk in the dark and it still works...I never packed a mal I could not land! ...mike----------------------------------- Mike Wheadon B-3715,HEMP#1 Higher Expectations for Modern Parachutists. Quote Share this post Link to post Share on other sites
mikeat10500 12 #20 April 6, 2003 Hook Laugh if ya want...but hooked that bad boy over a fence once at about 30 feet agl. I don't try to stand up the landings, but I probably could. I always pick the spot where I will land...sometimes it's not until 30 feet agl! ...mike ----------------------------------- Mike Wheadon B-3715,HEMP#1 Higher Expectations for Modern Parachutists. Quote Share this post Link to post Share on other sites
wmw999 2,334 #21 April 7, 2003 QuoteI have suffered two inversion type malfunctions on round parachutes (out of 70 jumps on rounds) Each has its advantage; but I'd have to say that's a really terrible malfunction rate, round or square. Bad luck most likely. I have a whole lot more round jumps than that, and no lineovers. A couple of cutaways when my stabilizers got tangled, but no lineovers. Each is anecdotal evidence. 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
E150 0 #22 April 7, 2003 I awlways thougth it was the other way round Quote Share this post Link to post Share on other sites
riggerrob 613 #23 April 7, 2003 QuoteQuoteI have suffered two inversion type malfunctions on round parachutes (out of 70 jumps on rounds) Each has its advantage; but I'd have to say that's a really terrible malfunction rate, round or square. Bad luck most likely. I have a whole lot more round jumps than that, and no lineovers. A couple of cutaways when my stabilizers got tangled, but no lineovers. Each is anecdotal evidence. Wendy W. I have had a total of three malfunctions on round canopies. My first malfunction was on a Crossbow (similar to a Para-Commander). I blamed the tangled stabilizers on another freefall student who was learning how to pack. My second mal was on a Canadian Army Military Freefall rig. They had just modified the sleeve retainer line and asked us to do a bunch of jumps on them to see if the modification worked. I suffered a total inversion and burned dozens of small holes in the canopy. Despite the reversed steering, I managed to land it beside the bowl. My third round mal was on a West German Army static-line T-10. The canopy suffered a partial inversion which burned dozens of small holes in the canopy. After I landed it, the poor canopy went straight to the scrap bin. Inversions are a well understood malfunction on non-netted T-10s. I have not jumped a round parachute since then (1986). Quote Share this post Link to post Share on other sites
dgskydive 0 #24 April 7, 2003 I have! Somewhere under 800 feet. Not something I ever want to do again. As far as rounds malfunctioning more than squares, The old saying goes "round is sound". I have seen thousands and thousands of round canopy jumps and been on nearly one hundred of them and have seen less malfunctions with rounds in all those jumps then I saw last week alone at the DZ. That being said I would still rather have a square reserve and main.Dom Quote Share this post Link to post Share on other sites
mikeat10500 12 #25 April 8, 2003 Rob Are you saying you landed and walked away from 3 round parachute mals...that could have been avoided? Who's side are you on? ...mike Quote I have had a total of three malfunctions on round canopies. My first malfunction was on a Crossbow (similar to a Para-Commander). I blamed the tangled stabilizers on another freefall student who was learning how to pack. My second mal was on a Canadian Army Military Freefall rig. They had just modified the sleeve retainer line and asked us to do a bunch of jumps on them to see if the modification worked. I suffered a total inversion and burned dozens of small holes in the canopy. Despite the reversed steering, I managed to land it beside the bowl. My third round mal was on a West German Army static-line T-10. The canopy suffered a partial inversion which burned dozens of small holes in the canopy. After I landed it, the poor canopy went straight to the scrap bin. Inversions are a well understood malfunction on non-netted T-10s. I have not jumped a round parachute since then (1986). ----------------------------------- Mike Wheadon B-3715,HEMP#1 Higher Expectations for Modern Parachutists. Quote Share this post Link to post Share on other sites