pchapman

Oh, right. I keep forgetting that as I'm at a DZ that has always required them and diagonal slides for the A, possibly due to a misinterpretation of RW requirements many years ago, that never got changed. Maybe it from when there was only one RW endorsement. So students get faced with pins, levels, turn & dock, sideslides & dock, and diagonals & dock in their minimum of 5 RW jumps for the A. Pretty tough, so the instructors go easy on the latter couple requirements. Ref for Canadians: Both PIM 1 and PIM 2A have the skills grid that show what's needed for the A and B CoP.

Sideslides are part of the RW instruction prior to the A license in Canada, and I was wondering about others' techniques. A standard one is to combine the upper body actions for a turn in one direction (twist the shoulders or dip an arm or however the DZ teaches) , and the lower body actions for a turn in the opposite direction. That uses two things the students have already learned, in a novel combination. But once I had tried something simpler once with the arms (in addition to the normal leg turn input), just shifting the arms sideways to push more off the air to one side - see the pic. A couple students I tried it with seemed to pick it up quickly. On the other hand, that arm motion isn't standard for teaching turns, so I'm not sure I want to teach it. Possibly useful, but less standard. It isn't like nobody uses it -- it does look like an input I've seen for stylists turning or maybe even RW guys sidesliding fast to a dock. Anyone got good ideas on teaching side slides? [inline sideslide-arms.jpg]

I see you had re-posted your message in the Condolences thread for Ahmed anyway, so you were able to express your thoughts. (http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=3194566) And there's a facebook group for him that still gets the occasional post: https://www.facebook.com/groups/12483762697/ Cheers, Peter started at GBSPC at Grand Bend occasionally drop by at SWOOP near Hamilton

Yeah you're right. They've had Vector III's since the late 1990s and never put anything in manuals in loop lengths, but sometime between the 2010 and 2015 manuals they added in references to it. And it is silly that they make it sound like a dimension which is not just a suggestion but mandatory, which would be highly unusual for normal rigging practice. (You don't want to have to be explaining something in court, saying, "Yeah, sure the manufacturer says that, but we all know that's B.S. if taken out of context.") Edit: You asked about specific container sizes. I don't always have that recorded and don't think I'll get into a big analysis tonight. But it looks like the 5.0" or slightly longer loops were usually on student gear with bulky reserves. (Some student gear could have quite sort loops - maybe due to wider containers allowing more spreading of bulk) Having a Skyhook adds another flap etc too but where it actually lies under the PC spring depends on the rig size.

Is loop length even mentioned in more recent manuals? I don't recall seeing it. It doesn't matter whether the loop is long, it matters whether there's slack in the way it is packed. (Skimming my packing records most of my Vector III packs seem to be 4 3/8" to 4 7/8" long but with a few lower and a few above 5.0" from the washer)

In my in-expert opinion, I find a lot of the closing loop length recommendations in manuals are optimistic.... Yeah manuals often have problems. Even from big UPT, manuals have often been way behind the times for gear and techniques, and one has to use supplemental documents. But they are getting better. One Vector III manual I have, the 30 MB MAN-004 rev 1 dated 2010, does have the hesitator loop included. I only skimmed it now but don't see a length recommendation. (They're up to rev 4, Jan 2015 now.) I could go on about manuals. Some companies don't even show you what the current revision is (that includes UPT) on their web page, so you have to download the damn thing every time to know whether you are using the updated version to be fully legal. Idiots.

Nice for someone to do some testing. For experiment 2, part 2, how about some intermediate stages that might more easily find an effect: Can one do any sort of test for acidity, where acidity is a good indicator of possible damage in the longer term? (Still got fresh enough Bromocresol blue for old Phantoms etc?) If looking for strength loss, even though polyester isn't the same as nylon, one might be more likely to find a measurable effect if using the sharpie to blacken something with less strength to begin with (e.g., F-111)?

It's kind of self regulating, isn't it? If you can do 15 tandems a day, day after day, in 30C heat then maybe you do that. If you're older and less fit or are an overexcited newbie and are wiped after 3 jumps (and 3 packjobs!), then that's how much you do. One could go on about different parts of the body -- suffice to say that generally any level of fitness, strength, and endurance helps. (But leg strength really isn't all that important.) Plenty of pretty ordinary or chubby or older people jump. We're not out to beat Jay Stokes. You ever jumped??

Ah, the name of a crowdfunded altimeter project. Nothing to do with radioactive materials for passive night lighting. Nice idea they have but just a bit crude in the current era of more advanced electronics and displays. Having just 1 light per 1000 ft, with no labelling, is a bit coarse. (Although then they have the under canopy heights too) And a 10 hour battery life is annoying, despite LED's obviously sucking up power.

Don't they still have some sort of fixed-cost repair service? (Or presumably they'll tell you that it isn't worth trying to fix, after having a look.) Maybe 5 years back I sent them my old trusted SSI alti (ancestor to the Alti-2 line) that was 15+ years old, that was starting to stick, and they fixed it up. They did a good job at a reasonable price. Whether the cost is worth it for an old alti is uncertain and you'll have to do the estimating. My old one started losing accuracy after another 5 years so who knows how much life each mechanical alti might have. It is sure to vary.

If one searches for the AP history course, there has been controversy online since mid 2014, so other articles are easy to find. One criticism was that some famous individuals were left out (e.g, Marty L. King). However, the authors note that the previous course did not include some of the same individuals. There was never any intent that the AP course information would be the sole source of history either in one course or through a student's time at school. The authors state it is a framework, not a full curriculum (1) Newsweek ran an article on the opposition, championed by one individual. Some of what he says highlights the issues for both sides:(2) I think the idea isn't that America is bad, but that there are different aspects to be examined to everything that happened. Who the hell cares about the valor of American soldiers? Congrats, job well done, thanks for your sacrifice! But how is their valor any different from the valor of British soldiers (yay!), German Nazi soldiers (boo!), Russian soldiers (boo until 1941, then yay, then after 1946, boo!)? The group that released the AP course framework stated that is there to foster critical thinking skills. I'm all for that, but am then surprised that a multiple choice sample test was released. Whatever one's political view (unless extreme), that dumbs every issue down to one short answer, which can't be good. I can see there are more subtle issues where one can debate the political viewpoint -- such as talking about immigrants, whether they are an important new labour force or displacing others from jobs and heavily dependent on benefits and transfers. Or what reasons there were for poverty among the working class 150 years ago, whether the interpretation in the sample was too simplistic -- i.e. low wages. (Yeah, but why? Low skills? Simply a less affluent society, less to go around? Lack of worker protection? It can be complex.) These were also discussed briefly in the Newsweek article, note 2. (I recall a Simpsons episode where Apu the convenience store operator was trying to get his US citizenship. When asked about the cause of the civil war, he starts to go on how numerous factors were involved, at which point the annoyed examiner tells him, "Just say 'slavery'".) That opponent to the AP course, Krieger, stated that it has a "revisionist, progressive bias.” I'm not sure about the latter, maybe that could be argued. But the way US history comes across to a foreigner, a "revisionist" bias sure sounds good. I do like the writings of Professor James Loewen, like "Lies My Teacher Told Me: Everything Your American History Textbook Got Wrong ". Maybe he is a little pinko or something, I don't know. While his viewpoint isn't necessarily entirely valid, my outside impression is still that American history is in great need of a little revisionism, to get away from the jingoistic hero worship and American exceptionalism. And the belief that America can do little wrong (with limited exceptions, in which case things are mostly better now) but in any case always with the best of intentions. Such things limit the ability to make good decisions, because if America is almost always right, then little thought is required and any policy decision made must unquestionably be a good one. "Team America, Fuck Yeah!" Note 1: Open letter by authors of the AP course http://www.edweek.org/media/letter-us-history.pdf Note 2: http://www.newsweek.com/whats-driving-conservatives-mad-about-new-history-course-264592

Thanks remwha, that saved me some typing. To reiterate somewhat: Unless there's a massive wind change "just below the aircraft", lets say within 1000' below the aircraft, then every exit and the next 7-9 seconds will look the same as it usually does. Every RW group presenting lots of drag to the wind will fall back more and fall slower, while every head downer will stay more forward and pick up vertical speed faster. All as normal. (Naturally the ground in the background will move differently depending on the wind situation, and that is a sign that separation might not be normal.)

I think there was a misunderstanding. Traditionally -- i.e., for most of the years the Vigil 1 & 2 have been on the market -- they do not shut off if they change altitude enough to think they are airborne. Yes, the newest ones are different, and turn themselves off at the 14 hr point in any case, like Cypres' do. So that issue of staying on, is addressed by the newest units. I think the serial number is a bit different than you recall, but for anyone reading, it is units with software v2.50 that have the automatic 14 hour turnoff.

Well Gary you did double-smiley that statement so between that and the pile of books you got, you've probably figured out that it isn't entirely risk free.... The following recent thread goes into a lot of the issues around what to do if family members aren't happy, plus risks and planning for injuries, although there are no simple solutions: http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=4697143;sb=post_latest_reply;so=ASC;forum_view=forum_view_collapsed;;page=unread#unread ("First AFF, Questioning My Choice" in the Women's forum)

Just an opinion: While it is fun to do something neat for an anniversary jump, don't make it too complicated. It is easy to plan something over-ambitious with too many people and too-varied skill levels, and thus end up doing just a big zoo dive. If keeping it really small one can do something more technical, while if making it bigger to invite friends keep it simpler. Heck it be as simple as a round belly formation, 360 & rejoin, backloops & rejoin, with the key being given whether or not everyone got to the original formation. That keeps things moving and not stuck for one person. While it can still turn into a mess, with reasonable belly skills it shouldn't be a dangerous one. That jump is maybe a bit boring but still an example of something out of the ordinary that gets everyone involved. It's still better than "we planned this complex jump but one guy was out so we just held on until breakoff", or "it was a complex sitfly but people were all over so nothing really happened". So that doesn't so much answer your question as give some suggested guidelines.

Ukskydiver and Parachutemanuals are great, but it is sometimes handy to be able to just search for & quickly open a file on one's own hard drive. I use The Parachute Rigger's Reference Library files for looking up old gear. But I got my copy of the CD's "from a friend of a friend", and at full price it is probably not worth the bit of convenience to buy the manuals off Paragear.

British BPA info suggests 4 injuries per 1000 jumps for AFF style novices. They publish decent risk info: http://www.bpa.org.uk/staysafe/how-safe/ (Their stats also show women tend to have higher injury rates than for men. To what degree that's due to physical robustness or spatial awareness or whatever differences, is a whole other debate.) I don't know the criteria but that probably would include serious sprains too -- anything which puts one on crutches even for a day or wanting to go for a checkup with a doctor probably counts as an injury. Similarly, a DZ I went to reported first jump injury rates of "about one a season" when doing 300-350 first AFF's a year. I would expect the risk to go down a fair bit after the first half dozen jumps, once the basics of flaring are learned. Although for some people, it doesn't become natural for quite a while longer. So one's risk over 25 jumps is probably not based on a 1 in 250 injury rate per jumps, which would be biased more towards all AFF students including those who only do 1 jump or under ten, without continuing to a license. (E.g, 1 in 250 risk would be .996^25 for 25 jumps = 10 % chance of injury before getting licensed. Sounds too high.) It isn't uncommon for a student to be a little sore after some landing of theirs, but to actually break something is rare.

There are significant US & Canadian differences. We don't have the TSO system in Canada, and our parachuting regulations are mainly from the voluntary organization CSPA and only a tiny bit from the gov't (Transport Canada) -- not like the US where a lot of regs are from the FAA itself, when it comes to gear & rigging. So under the FAA regs, only a Senior or Master rigger might be able to legally do things to even a main parachute. (Jumpers themselves can do some basic assembly but not modifications. There are other threads debating US rigging issues, as in the States it is quite normal for riggers and jumpers to go beyond what they are legally allowed to do.) I guess the seamstress thing is covered by the factory being under the supervision of the appropriate rigger (whether or not they actually inspect every sewn seam!)

In Canada in general you can jump such gear. Your local CSPA DZ may not choose to do "non CSPA" jumps, and probably won't. But they could decide to cater to the BASE crowd and send up a load to 500' if they so chose, stating that it isn't a CSPA load. Unless there's some hitch I haven't heard of, which is possible. E.g, a) the DZ they've signed something saying all jumps they do must be CSPA style ones. (Well then they just rent the plane out to someone else so the DZ isn't the entity offering the jumps) b) if somehow their Transport Canada Operator Certificate also had something in it about following CSPA rules. c) Or if some Memorandum of Understanding with how they integrate with air traffic control is similar. d) Or I don't know if CSPA members somehow agree to always follow CSPA rules, even when not at CSPA DZs. So there are some interesting things that could be looked up to see how it really works out. But that's a whole other topic. As for "laying aside a rating", why would a member of the public have more rights than a rigger? One's aunt is legally allowed to sew up D-bags (or a whole rig) but the rigger A can't?

But the thing is, one can just lay aside one's ratings and sew as a member of the public, on a main, reserve, or harness. Transport Canada has no rules on what gear to use except for official demos, where it is basically TSO gear. (One can legally jump uncertified BASE gear from airplanes in Canada.) If jumping at a CSPA DZ under CSPA rules, CSPA rules say you need to have a reserve parachute inspected & packed by a Canadian or US rigger within 180 days. (USPA DZ's in Canada will have similar rules, and CAPS too if any still exist.) There are otherwise no rules about TSOs, manufacturing, manufacturers, etc. You just need a rigger to believe the rig and reserve are safe enough to jump that they'll pack it. It's always possible you can find some rules I've missed and I'm fine with that. It can be tough to find how they all fit together. ========== Background that you would know. By PIM1 2014, rigger privileges include beyond the packing stuff: Rigger A - remove and replace component parts; make minor hand repairs Rigger A1 (only existed in last couple years) - make basic patches, change lines, "manufacture simple components" Rigger A2 (only existed in last couple years) - complex patching, simple harness repairs, "manufacture components"

Maybe it's the local culture. There often haven't been Rigger B's or Master riggers around where I am in southern Ontario, even though it is a reasonably big Canadian skydiving market. Every rigger just sews whatever he wants, and uses his judgment as to what he does, apprenticing and practicing as necessary with whatever machinery is on hand. If everyone followed the rules all of a sudden, nothing would get done except in a very few limited places. Of course we don't have TSO's in Canada so you're not breaking any gov't rules, only exceeding what one is allowed by one's CSPA rigger rating if working on gear. And do CSPA rules on not sewing by a Rigger A even apply if building stuff? After all, we don't have rules on main canopies like the FAA has in the US. So couldn't a non-rigger build parts, because there are no federal laws here? So it is almost like one can do more with no rigger rating, because a non-rigger hasn't gotten any rating that restricts him to certain tasks. The DZ where I worked after getting my rigger rating has a few sewing machines, and there's almost never been a Rigger B around in 25 years. The DZO didn't have a Rigger B, I didn't have one, but the current guys have US Senior ratings. So they're allowed to go sew stuff after doing a single course, something not possible with the Canadian system. Mind you the US certified riggers are supposed to follow FAA rules and manufacturer directives, so if following the rules properly (as Masterrigger1/MEL reminds us), then there's a lot that Senior riggers aren't allowed to do even on mains. In a way it is handy that there is much less guidance for Canadian riggers. Gives us the flexibility to do more of whatever we believe is right, and ignore anything stupid to come from manufacturers, based on our best rigging judgement. (Naturally there are areas where custom and rules are stricter -- eg, AAD maintenance.) Heck I've done a couple sewing repairs on reserves with a Rigger A rating, because if I didn't do it, it wasn't going to get done. It's not like I was taking food from the mouth of a Rigger B nearby. One of the best local riggers now has a Rigger B and builds containers, but when he was fresh off the boat (so to speak) and rigging, he was probably doing so with only a Cuban rigger's rating. For a long time he was building all sorts of stuff with his Rigger A rating, so he probably had no problems when he sent in his materials for the Rigger B and got that. So whether the local role models were someone like him, or a local DZ, the attitude has long been to just do things if one thinks one can do them safely. As applies to much of skydiving. If one can also make a better product and/or cheaper, then one gets more business. It does mean, for better or worse, there hasn't been a lot of emphasis on upgrading ratings. (With the Canadian A1 and A2 now, the system if more professional in some ways, but a lot more expensive and just pushing people to get American ratings.) I haven't personally seen many problems with equipment produced by local riggers whatever their status. There are always some items that aren't that great or don't work so well, but there's no rule on not having crappy old gear from manufacturers that doesn't work well either. It would be interesting to get a list of local Rigger B's and Master ratings, and see who is actually still around and active. I don't know how the situation is in Quebec for riggers...

I'll disagree. Maybe we aren't really arguing because we're using the term in different ways. Of course everything can be calculated down to numbers, whether stall speed, control forces, etc. But then nothing in the universe is subjective because it's all just physics. But flare IS very subjective because there's a person controlling it. Changes to where the flare power occurs, and total flare length, and pressures, will affect how people land something, especially if they are not used to that particular combination of controls. A quantitative characteristic in a vehicle (parachute, airplane, motorcycle) such as those for a very light and short control stroke for a given output, will have a strong subjective component when humans are involved as the controllers. A vehicle like that might be seen as very good/bad/responsive/twitchy/uncontrollable, depending on the design and the user.

I was curious about that so went and looked at their product literature and line trim charts and was quite surprised at how little has changed. Whatever they've achieved different between the two canopies is due to subtle changes. (And perhaps a small amount due to the material, but that should affect packing more than inflated shape or aerodynamics, especially when new.) The spans and chords and aspect ratios are identical for identical sizes. Maximum weights are increased for some models of Optimum, generally for the larger sizes to expand above 254 lb, but also in one smaller canopy, moving the boundary between 254 lb and 220 lb certification down by one size. (Opt 113 is good for 254 while the PDR 113 is only for 220.) Maximum suggested weights are generally the same. (However: Higher for those Optimums where the maximum certified weight went up. For very small reserves, occasionally the Optimum allows a slightly higher weight for more experienced jumpers, and expands the Not Recommended range for less experienced jumpers, making experience level slightly more important.) As for line trim charts: I looked mainly at the 143 model. (PDR revision E is current, OP revision A is current) Sliders are the same size for the 143, but a little bigger on smaller Optimums because their slider stays the same while the PDR's gets smaller. For big sizes, all are the same, keeping the same slider size as the 143. For the 143's, the A lines lengths are the same, as are additional B, C, and D distances. This suggests the attachment point geometry is likely the same too (same distances along the chord). For the 143's, the distance from the A's to the brake line attachments goes down 3.75" -- in effect adding more breaks. For the 143's, the lower steering line (above the eye) becomes shorter on the OP basically by the amount to make up the difference seen above (within a quarter inch)(and suggesting the cascades didn't change). For the 143's, the brake eye to toggle length goes up a whole 6". So some of that goes into making up for the shorter distance above the brake eye, and there's an extra couple inches of slack in there too. Maybe that helps the modern jumpers a little, those who expect the flare power lower in the flare stroke, but it really isn't much in that regard. The 99's are like the 143's: Zero change in trims, only some changes in brake line. Things can be different at different sizes though. Looking quickly at the 253's, there the basic trims are not the same, the PDR and OP have pretty much all numbers changed by up to 2". Just about everything was tweaked or revised. (One apparent large change is the LST shrinking by 11" or so, but brake cascades must be lengthened nearly as much, as the position of the tail relative to the A's is only slightly changed at about an inch shorter.) Brake to toggle length goes up even more, this time about 7", and that's with little change in the tail's position with brakes set, and probably not much in the general geometry, so a lot of slack is added. ===== For the 143's, with A,B,C,D trims the same on the same planform, that suggests the trim angle is the same too. I would have guessed the trim would be steeper for example, in order to give the Optimum more speed for an easier flare with more of a time window. But that's not the case! Indeed PD says the Optimums have a slightly shallower glide than PD-R's. (Technically one could change the trim angle if all the B,C,D trim points shifted along the chord, but that scenario seems unlikely, with actual trim values maintained exactly.) So where do the differences in the PD-R and Optimum opening characteristics come? For the 143's or 99's, so little has changed so that it comes down to only the deeper brake settings, or the fabric. Well, sail vs. ZP vs. F-111 does affect openings, so maybe the low bulk fabric behaves differently too when flapping around and subject to high pressures (even if it meets or exceeds F-111 style permeability in normal tests). Similarly, how about the landing characteristics? PD says the Optimum has a longer control range and even better flare. Does it actually stall slower or just have a longer stroke that changes the feel? Does the slightly lower angle of descent make it easier even though diving more for the ground would usually gives a canopy a better flare by giving energy for the flare? So with some things not changed at all, but some tweaking, plus the fabric change, it is hard to tell where the changes in opening and landing characteristics come from, at least from this analysis. [Edit:Or is there a change in the airfoil?] There's some PD / LeBlanc magic still in there...

He has good stuff but with the caveat (for those who haven't clicked through) that it is BASE oriented so that concerns may be different. One can pack for skydiving and not give a damn, in ways that would not be optimal for low altitude freefall BASE. Still, his work gets people thinking about the mechanisms of how pins pull.

An unfortunate side effect of that solid Vigil case. Friends and I had a similar problem in the US once, but they let us through in the end. Can't recall if they did an extra swab test.