pchapman

For many years I've used 2 elastic straps on my good old SSE Altimaster II. One strap between the mount holes at the top corners, one between those at the bottom corners. The straps are from a sewing store. Holes can be drilled out more if one wants to thread a bigger strap. With the elastic straps the alti can be put on very quickly; no fiddling with trying to thread a strap through a narrow plastic slot like typical hand mount small altis. Down side is replacing the elastic every year or two, and the alti isn't as snug on one's hand as a normal Alti III mount. Round cross section bungees work too and are more durable but aren't as comfortable. That's the way I see it done for all the student altimeters.

He's right, I was wrong. Some containers for T-10's, Para Commanders, etc, through the 60s at least, were cotton. And it's right in Poynters too.

There seems to be some competition out there! In the latest issue of a European paragliding magazine I receive, a review of speedflying style canopies shows that there are 19 different paraglider manufacturers with one or more different canopies available. I'm not sure what the market can sustain in the long run, but it seems that most players in the paragliding market believe they need one in their product palette. Too bad that PD couldn't get into the market, whether it is due to reasons of technology, cost, user's desired flight characteristics, or distribution reasons.

Who knows, it is possible. One rigging attitude is to not pack something if one doesn't feel comfortable with the safety overall, according to more modern standards. A different one is to pack something if it meets all the regular standards according to the normal rigging tests. The ad of course fails to mention what canopy is in there. In rigging we don't have a good handle on loss of strength of webbing over time, and we don't (in US & Canada) have arbitrary life limits. The military will have better data but it isn't something most riggers have access to. So a rigger might have packed the thing, saying that the webbing looks OK the best he can tell, and that he pull tested the hell out of the canopy but it passed. Maybe he hoped the thing would tear, but it didn't, so he had no hard evidence that the rig was unairworthy. I had a situation like that one time when I was faced with a 40 year old ex-military rig for a glider pilot. I packed it but gave the guy plenty of advice on why he might want to upgrade. A buddy's belly wart reserve container for his Para Commander rig is a '57, but the canopy is newer and it isn't as if he's hawking the thing on eBay. By '58, containers should all be nylon, considering the US was getting into nylon before the end of WWII. To find an old belly wart to practice packing on, another avenue is to find a DZ that's been open 30+ years, to see what they have in the closet!

Very useful to hear that, to contrast with an argument I've been told a couple times: "We don't need helmets on our instructors because we're jumping from a big plane (Otter or Caravan) so it isn't like you guys trying to squeeze out of a 182."

MotherGoose knows this but for completeness: In Canada, at CSPA dropzones, jumpers acting as Coaches or Instructors must wear a helmet. (Not that that is always followed.) (Helmets are actually required for all jumpers, except those with a D licence, where the DZO allows it.)

Replying to some of the comments: - I felt comfortable when chopping and going back to freefall, but it was indeed too low. Should have had a higher planned chop altitude so that if I was a few seconds late and busted the hard deck I'd still have more margin. - When I chopped and half rolled to get belly to earth, it was a surprise that I had too much momentum and went past it, and so had to keep going once more around. Like many chops from mals, if one is trying to get stable before pulling, it can take a bit of time and a few hundred feet. (Between video and Protrack, it seems the chop to the pull took about 2.5-3s and 250-300ft.) If things had gone really wrong and one couldn't cut away at high G or whatever, the last ditch plan would have been to just dump the main. Even with a canopy entanglement it might well slow things enough to better allow chopping the 37, then the main, and then go to reserve. - I have to learn to put on the dry test pilot voice when I do odd things on video.

So, what's new in the world of flying miniature canopies that are intended to be cut away and not landed? At the end of this post I've put together a quick list of some of the miniature canopies I've heard of. Any others around? Here's the little story of the one I built: A year ago I figured as a winter rigging project I'd build a miniature canopy and jump it. Not having the resources of a parachute manufacturing company, I took the easy way out and modified a stock canopy. Taking an out-of-service Stiletto 97 with 3000+ jumps on it, the center 5 cells were cut out and it was sewn back together. Voila! It wasn't quite so simple, as the tail got trimmed too, brake lines had to be repositioned, and a new bridle attachment with reinforcing tapes inside the canopy had to be created. An old pilot chute was cut down to 16" in diameter. The full length lines were retained, avoiding a lot of trim length recalculation and sewing. I figure that with the long lines and the new aspect ratio of only 1.4, it might lead to slower spiralling and lower G forces if things got out of hand, compared to the very short line length canopies that have been jumped. So far I've made just one jump on this 4-cell, "Ex-Stiletto 37". Yes, PD know about this slightly modified product of theirs and got a chuckle out of it, although of course they advise of the dangers. It was jumped using a harness set up for deploying a 3rd canopy from a belly container, worn beneath a regular rig. I did make sure to build the cutaway harness with a big, easily grabbed loop-style cutaway handle. The canopy actually flew OK despite the lack of trim changes from when it was larger and more efficient. But it was hyper-sensitive to input, spiralling at the slightest provocation. Not so cool was that with all the spiralling I did let myself get sucked lower than the already low-ish altitude planned for the cutaway. So the chop was a little below normal minimum pull height, before going to a large reliable F-111 main canopy. It felt like chopping from a mal, which in effect it was. On a back-to-wind deployment off the step of a C-182, the canopy snapped open quickly but not hard at the slow airspeed. Stability was better with the brakes set, which might be the safest way to fly it. The canopy got squirrelly when releasing the brakes, despite trying to pop them simultaneously. With the short wingspan but long lines, the slider sat less than half way down, but that didn't influence the flying. Small inputs, whether by harness or just pressing against a riser, would send the 37 into diving spirals. A difficulty was that if it whipped into a turn, one would shift in the harness or press against the risers, suddenly changing the turn again. The G loading in spirals felt quite normal. Given that I was going in and out of spirals all the time, the Protrack data isn't too useful, but descent rates stayed between 40 and 70 mph the whole time under canopy. Eventually I did get myself line twisted. Ironically with what was now effectively a single point suspension, the canopy showed its inherent stability, levelled out, and flew straight on its own -- but it was time to chop. A few photos are included here, shot with a big lens from the circling C-182, and I had posted a video at skydivingmovies.com last fall: Ex-Stilletto_37_flight__intentional_cutaway_low_res.wmv Background on other miniature canopies that I've heard of. No guarantees of being right, but this is what I understand from dz.com etc.: For landed canopies, the VX-46 was landed by a number of people, but Luigi Cani then took things down to the VX-39 and then the JVX-37. Above that size there have been various canopies in the 50's and 60's size range that people have jumped regularly. Luigi has put a lot of time into small canopies, but even he had to work his way along. In 2004 it was written on dz.com, "Luigi said he couldn't even hold the 39 on heading at first, and that's after plenty of jumps on the 46." The Xaos 21-21 was jumped by a few people (C. Martin, J.Provenzano, A. Farrington at least), and used for the wingsuit/canopy docking in Eloy in 2004. (The dock was after the original Jari & Vladi wingsuit/canopy dock in 2002 with a modified but landed Velocity 84 system.) A Cobalt 40 cutaway canopy was being jumped, including for a wingsuit/canopy dock in 2005 at Burnaby, Ontario (S. Curtis, S. Gouws) A Cobalt 25 was jumped (by 'catfish and eric') in 2002. There was talk of a Firebolt 18 having being built but I never heard of it actually being jumped. Ted Strong built 14 and 25 square foot canopy and jumped them back in about 1999. He mentioned this on skydiveradio. He had one OK jump, and a few others where the canopy immediately spun up on him, so he didn't continue with live tests. In sport skydiving, there's perhaps less enthusiasm about miniature canopies after Chris Martin died in 2004, although it sounds like there has been plenty of development of ultra-high wing loading canopies for unmanned military payload purposes.

I find the Racer is one rig where I like to use a molar strap. With the various packing methods I'm used to, the freebag has nothing to hold it compressed during a big part of the packing process, unlike a molar freebag or even a regular single pin freebag with a temporary locking cord through it. So the bag bulges and doesn't restrain the canopy well -- when you prefer it to be well restrained to provide the 'well' for the pilot chute in the middle. Just my personal preference.

So you figure the R44 still is OK in mass and control characteristics for having 200 lbs move out to a skid and then drop off? Not knowing helos well, that's what I'd ask more about as one goes to lighter helicopters. The equivalent in normal helo ops would be dropping people off to the ground when hovering a couple feet above rough terrain. (Would it be worse in a hover than in good translational lift?) Maybe it's only at the level of very light 2 seaters that that kind of movement and then sudden loss of mass would start to be a serious CG and control issue?

7 cell, 156 ft sq, 80 kg max ("recommended" I suppose) - briefly mentioned in Poynters II I only have a couple pages from the manual, which shows an odd and intricate flat pack method, perhaps from before propacking reserves had really caught on. I'd ignore those old instructions anyway. Unlikely to be TSO'd.

All other things being equal, to get 4 or more incidents out of 7 happening to females, if the proportion of female jumpers is 20%, is only a 3.3% probability. That's from the cumulative distribution function of the binomial theorem. I have no stake in this; I was just curious whether the 'odd' numbers seen by jtnesbitt were likely to have occurred due to chance or not. Since "all else being equal" is never quite true in real life, was there anything else that stuck out in your analysis, JT? Low experience level perhaps?

A photo I took of an A-1 spider type pilot chute is attached. The big spring mechanism that attaches to 4 arms goes inside the pilot chute, so it is inside out in the photo. This one was built in '59. It's an early design... reading Poynter's I see that the classic MA-1 vane pilot chute was preceded by the A-3, which in turn was preceded by the A-1, the early ones of which were made of silk.

Would you like to share any information or just tell us that you know more than us?

I can't really answer your question but I looked up what little is in Poynter as I had never heard of the canopy: 5 cell, 190 ft sq., F-111 fabric, 400 lb lines, bag deployed, hole cut in slider. TSO'd in the Low Speed category. Weight 7 lbs. Introduced April 1981. [Edit - found more:] Pioneer once had a service bulletin covering what seems like all of their main and reserve canopies. Some of the dacron lines they used had resin that made them a bit too sticky and stiff, so all the canopies had to be inspected. Basically if the lines seemed OK, they were OK, if they were too sticky, one could wash and talcum powder the lines & return the canopy to service. Plug: This bulletin popped up in the Canadian (CSPA) Technical Bulletin list, an online copy & index of which is made available through Skydive Kamloops. http://skydivekamloops.org/rigging/tb/TB27.pdf

How unusual was it for students to jump Para Commanders using a no-cutaway, no pilot chute in the belly mount reserve technique? One school in my area used to use Para Commanders in that way for students after they graduated from T-10's. I always thought that was a bit odd, given the Para Commander's reputation for spinning in a mal. What was the general opinion for anyone jumping PC's with manual reserve deployment procedures? (On a related note: So when did 1 1/2 shot Capewells start to be used, relative to "high performance" rounds like the Para Commander?)

For anyone scared of the "17 ft" round, I'll note that it APPEARS that GQ uses INFLATED diameter not constructed diameter for rounds. Even their modern rounds for civilian pilot bailout rigs are typically quoted at 4.8m diameter, which is 15 3/4 ft, clearly a different measuring scheme. (And amazingly the accident report for that possible roll pack fatality showed up on the web at http://www.atsb.gov.au/publications/investigation_reports/1974/AAIR/pdf/197400007.pdf. Poorly sequenced round openings can be bad -- that one was deployed by a tumbling jumper at terminal with nothing out, from a belly mount, with no pilot chute, and no diaper (I presume as it was '74). Yuck. It inverted during deployment and burned big enough holes that it wouldn't stay inflated.)

They're hardly that bad, even if landings can be a bit athletic. I think there are a bunch of people who stalled out Microravens on landing over the years who would have been better off under rounds! Peter (My 1st reserve ride was a Phantom 24 in 2002, backing up in 15-18mph surface winds. Rolled that one out, unlike my ParaCommander mains, which I usually stand up.)

To deal with that aside: The ParaFlite Evolution was not much like the cross braced PD Excalibur. The Evolution was a partial ZP and later full ZP canopy with a lot of unusual design quirks, from the early days of ZP canopy design. I have a post or two about them on dz.com.

I like the common sense approach that mid cycle open & recloses are OK. But it says, "The rigger who reseals the container is responsible for the airworthiness of the parachute system at the time it is returned to service." One may just have to ignore that and accept the risk, if one thinks (as I do) that the concept is B.S. An aircraft mechanic who is asked to inspect the spark plugs only can't know if the elevator cable is fraying and shouldn't be held responsible for the airworthiness of the entire aircraft. If there were a problem with a mid cycle reclose, I'd just argue, "Yes I'm responsible, but obviously in this context it means that I can only be responsible for the things that I can see during the open & reclose. I can't be responsible inspecting things that are invisible, duh!" Whether or not one buys into what may be an illogical extreme, it still suggests that one must inspect the things one can inspect. So for an open & reclose, one must budget for a full external inspection of the rig. It wouldn't be an excuse to say, "I didn't look for or find the broken harness stitching, as my customer specifically asked me to replace the cypres battery and not to waste his money on anything else." Riggers will probably just continue to do or not do open & reclose jobs according to their personal preference.

I'll disagree in principle with LouDiamond's saying that with big changes in direction, the spreadsheet method will result in errors. (B.S.!) But in PRACTICE, I'll agree. (Good point!) It isn't that the math is fundamentally and magically wrong when there's a shift of over 90 degrees. But the solution can become very, very sensitive to the assumptions made. And many assumptions have to be made when designing the software. At small distances, a predicted direction may not make sense. If the spot is calculated to be 10 feet from directly overhead (or something like"0.023 miles" = 120 ft), it isn't that useful to have the computer spit out a jump run direction which could be north, south, east, or west. The jumper is exposed to the wind at different altitudes for different times, depending on rate of descent in freefall and under canopy. Does the calculation include extra sub-terminal time, or for simplicity just assume terminal speed? Belly terminal, right? And for the longer period when the jumper is under canopy, at some assumed descent rate, does one assume the jumper is open at 3000', 2700', 2500', or what? That becomes critical in this example with wildly varying winds at different altitudes. Aren't wind forecasts feet MSL? So does the software assume the DZ is at sea level or is its MSL altitude taken into account? The software likely assumes the perfectly spotted jumper should drift to the target as he touches down. Who knows, someone else might decide to write software so that a jumper would drift above the target when they reach 1000', so there's still time to set up a proper circuit at a busy DZ. One also needs to know if the calculation simply uses blocks of air at a constant speed, or averages between the reported heights. E.g., is the 3000' value assumed to take place everywhere between 3000' and 5999', or 1500' to 4499', or only at 3000' -- with it linearly averaging up and down to the ground and 6000' values. To get ridiculously fancy, one could vary the wind speed from the ground up using an exponential curve to better simulate actual wind shear profiles in a viscous fluid, for which one must also take into account the height over ground that the "ground" reading was taken, and the degree of turbulent mixing of the air in that day's weather conditions. The calculator in this case doesn't seem to deal with minor changes in forward throws for the three different aircraft types at the DZ, but presumably does take into account different speeds and number of jumpers, as the spots end up the same but the green light location differs. The calculator also assumes the 182 drop height is the same as the King Air and Twin Otter, as the spot results are the same. (i.e., the 12000' winds influenced the jumpers for exactly the same length of time.) In this particular example with crazy winds from 090 and 270, I'd make a judgment call (other than staying on the ground!) about how far up the ground winds extend compared to the 3000' MSL winds. That's the critical thing here, the region under canopy where most of the drift will occur. So there are many assumptions that go into calculating the spot, each of which might result in answers different than 0.023 miles at 92 degrees.

This old thread about one of NWFlyer's early "adventures" seemed an appropriate place to add another data point about losing functional consciousness under canopy: I was in a CRW formation last year, holding a 2-stack for what must have been over 10 minutes. (We got docked at say 10,000' while flying tandem canopies solo, after dropping our passengers, but that's another story.) The other jumper docked at the top of my canopy had his legs pulled back behind him, while he had his ankles hooked into the top of my center A lines. As we descended more, he mentioned some discomfort but wanted to keep going, as he's a pretty tough guy when it comes to jumping. Hell, he was doing CRW in sandals on an HMA lined canopy. At a couple thousand feet he broke the formation, letting go, so I figured he didn't want to land the stack. While I set up for landing, I didn't pay attention to him as he sailed off into the distance, finally turning around to just make it back to the main landing area. For at least 5 minutes after landing, he was really groggy and just stayed sitting down on the grass. It seemed to all have been from hanging in the one body position for so long, unable to move his legs, and leaning forward against the leg straps. He wasn't able to realize what was happening, and was no longer functionally conscious. I don't know what exactly his state was, but it was semi-conscious at best, as he relaxed his grip on my canopy and went sailing off into the sunset (or actually 90 degrees to it) until he woke up enough to steer for home.

Hi Lee, They were Canadian made, popular locally in their time. I've got one in my belly mount too.

(We'll get this to bonfire eventually.) It looked like the guy who was going to kill himself skydiving, was going to do it with his Vector I or II. No matter. It's still a bit of publicity for skydiving. It kind of ruins a show one otherwise likes, when one realizes they make everything up and really don't consult with anyone. There wasn't really anything in the show about flying light aircraft or skydiving that was in any way correct. They mentioned Perris, and got in a basic Perris, CA vs. Paris, France joke, but then didn't even take their camera crews across the state, creating a lame DZ hangar instead. The detectives look at a whiteboard listing all the info about jumper's jumps, including exit and deployment altitude. On that board it shows that their suspect had been doing a lot of jumps from 8000 feet. They conclude that he must have been training to jump from that height. And, suspiciously, that's the same as the cruising altitude of the Cirrus single engine aircraft he was thought to have jumped out of (in which a guy was murdered). I never realized how much one has to train to jump from 8000'...

"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.