pchapman

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Everything posted by pchapman

  1. While councilman must have the answer, the reason might be (if it isn't just a worn data panel) that the Swift Plus' "normal size" was likely the 175 (close to that of the original Swift), which is why it might not list a size. Only the subsequent little version and big version would have a number added. Sort of like how a Glide Path Fury is just a "Fury", and is always 220 ft sq. -- however there's also a "Fury 200" (quite rare in that case).
  2. Yeah, heavy spring loaded PC's at the few DZ's with such PC's do fall in front of the canopy sometimes. Note that since they are spring loaded, they don't collapse so have some real drag. Worst I've seen is one dragging straight back under the center cell. That distorted the nose somewhat, but no problem for landing on a big student canopy. Sometimes happens more to very light jumpers, where I think the canopy doesn't shoot off horizontally as quickly at the end of opening, and so there's more chance for the heavy PC to drop down and happen to fall forward of the canopy. Also seen it on tandems. Big somewhat heavy drogue at the end of a long bridle. Also can fall over the front. Landed one once and seen others a couple times; no problem since the drogue is collapsed, even when it sat out near the wing tip. At least, that's what I've seen.
  3. Compair aircraft, spinning, in south America perhaps?
  4. It does indeed take some explanation. For example, that one can relax too much too. Lower legs bouncing in and out randomly in the air stream, strange body positions on a tumbled exit, etc. One has to apply some muscle power to attain and hold the desired body position (arch and all that), yet still not be rigidly stiff. So shouting at a student like a drill sergeant to RELAX!! isn't correct?
  5. Yeah in North America a Mr. Bill normally implies two sport rigs. But it has been done hooked up as a tandem passenger with sport rig, if you have a DZO that doesn't mind you renting his very expensive gear to do stupid stuff on, something that might not quite fit the user agreement he signed with the company he equips his DZ with...
  6. Looks like this thread has both US and non US canopy companies being listed. Who else is non US? (My knowledge is pretty limited, and I'm not looking at docile canopies specifically) Parachutes de France (don't market to the US) Firebird (Germany) Paratec (Germany) Basik (France) has a reserve and seems to have a couple mains too now Atair (Slovenia) is more for BASE but has a couple skydiving canopies I don't know to what degree eastern European gear gets into the rest of Europe, but there are companies there, such as: Polyot Ivanovo (Russia) Your profile isn't explicit on where you live. European companies tend to be largely unknown as sellers in the US, but a very few have dealers / distributors in the US (e.g., Basik).
  7. Hallelujah! We have a new convert -- who is a teacher to a lot of other skydivers and can help others understand too. (If he doesn't keep on just going on and on about canopies.
  8. No, it has nothing to do with separation. Except for any spurious reason because by the time someone looks at the previous group and thinks, "uh, that must be 45, they are pretty far away in any case", 5 seconds has probably elapsed so you've added some separation before climbing out. Or if you happen to notice a head down group not falling back as fast, maybe you take more time. But that has nothing to do with 45 degrees specifically. It has been suggested that one might as well count the fleas on Bill von Novak's dog. Do a slow mental flea count to 10, do a slow climbout, and most days, you won't die in any case. Why is 45 wrong? 1) Read some of those long exit separation threads scattered across this site. 2) Bill von Novak's video shows multiple groups falling away for many seconds. They are always below the 45 degree line and never sweep back far enough to hit it -- except sometimes for a trivial moment just after exit, within the first couple seconds. (I haven't seen the video lately but one place with a couple stills and exlanation by von Novak is at http://www.pirep.org/forum/viewtopic.php?t=1180) [Edit: more stills posted by Bill v N in http://www.dropzone.com/cgi-bin/forum/gforum.cgi?do=post_view_flat;post=951741;] Makes sense: near the airplane the airplane is still moving 80 kts or whatever forward and the jumpers quickly decelerate from that horizontally (belly fly), and are just picking up vertical speed. Since it is all the same air mass near the plane, for a moment they drop aft of the 45 line. Later, the plane is still doing 80 kts horizontally and the jumpers are doing 100 kts+ vertically, so the jumpers, the rest of the way to opening, are below the 45 degree line. For freeflyers, low drag head into the wind on exit, they probably won't even drift back near 45 degrees at any time. [That's for all sorts of typical into wind flights. One can create special scenarios with low uppers and 120 kt lowers where jumpers would drift back past 45 degrees. But that doesn't matter if it is shown that in all sorts of regular situations, the jumpers never go aft of 45 degrees except possibly just after exit.] 3) It has also been pointed out that if the big changes in wind speed don't occur near the aircraft, there is absolutely no difference in the angle of fall relative to the aircraft from day to day near the aircraft. So whether you look at a real 45 degrees or some other fantasy 45 units of angle, you would see no difference on days with different winds. If the uppers from 10,000' on up to jump run at 13,000' are 80 kts , a 4 way team will fall away the same on every day (for 20 seconds), whether the winds down at 3,000' are zero or 80. Now if the differences in wind speed are spread out evenly across all altitudes, sure, there'll be a little change in angle from day to day. But that may only be a few degrees in difference between a strong and low upper day, and probably impossible to judge. (e.g., I calculated for a day with calm winds at opening and 40 kts at jump run, compared to a calm day, and found about a 3 degree change between the two days, for jumpers who have been in the gradually changing winds for 12 seconds after exit. Not bloody likely that you can tell the difference. Plus it still has nothing to do with "45 degrees".) Some concepts take some thinking through to understand and be personally convinced. Read up and give it a good think!
  9. One look at that handle system and the first thing anyone with any mechanical aptitude is going to say is, "uh...that might massively increase pull forces". I can understand if some subtle thing were missed in testing, but it is so ludicrously, freakingly obvious that that system might fail and needs careful testing. At least it wasn't exactly a mass market product aimed at newbies.
  10. Someone got the link to the one 45 degree video, the one helping dispel the 45 degree idea? I've lost it among the long 45 degree rule threads. It would be great if someone else made a video too so there would be some independent evidence. (I don't believe in the 45 degree rule, but it would be useful to have more evidence to confirm the argument.)
  11. Plain old jump numbers are one component of the requirements for different USPA licenses. Unless you don't care at all for any privileges that come with additional licenses, you might as well add the jumps in, if the DZ can help you verify at least the overall numbers.
  12. It appears that in Australia a pilot only needs to be stable on the medication for 28 days before resuming flying duties, unlike the US 1 year. That's a very progressive policy, based on a decade of research they did. (There are of course psych evaluations to be done for the pilots; it isn't just a matter of getting a prescription & taking a month off.) So for American pilots (&TM's) with depression who think it is going too far to be grounded for a year (or previously, entirely grounded), are they uppity and do they have out of control egos? Rules and laws do change over time. I hear they are letting women vote now too. Much of the medication issue comes down to whether one believes it is safer to fly with untreated depressed pilots or ones receiving controlled treatment. It's not a choice between perfect pilots and imperfect pilots.
  13. My uninformed guess as a starting point: Singer 68 rather than a 69.
  14. That came up in a thread in Bonfire I think a couple months back -- but the thread didn't attract much attention. It does suggest that eye movement (shifting the angle of gaze) is useful to avoid having the brain lose track of small objects. But it does involve large areas of movement making objects that are not moving on the focal plane disappear. So exactly when this issue is most likely in the skydiving context is unclear to me. We might have situations where everything is not moving. E.g., background sky & ground essentially not moving, and a canopy on intersecting collision course with no relative movement. But then if we are turning to create a moving background, other canopies in the sky would also tend to move across the visual field. So it is harder to find cases of large areas of movement combined with small non moving objects. Still, it is an example one of those visual problems (like plain old foveal vs non foveal vision) that can be minimized through the use of continuing brief eye movements, stopping at different points while scanning the the sky around.
  15. Some standard prices: Paragear '93-'94 Cypres 1 = $1225 Paragear '11-'12 Cypres 2 = $1425 Someone wanna run the Cypres 1 through the inflation calculator?
  16. Sometimes we prefer to email companies because it should be LESS of a bother for them, so they can attend to the matter when appropriate. So we're doing something to help them, and we'll be even more frustrated if they then seem to ignore us. Sometimes I try to initiate contact by email but say that if the company and I need to work out details, let's talk on the phone -- that's where your idea of the fast back and forth works well. Then sometimes it is back to email at the end so they don't misunderstand something over the phone, such as an address.
  17. Well then ... what are your beliefs or procedures for dropped toggles, or what teachings have you seen? I've never heard anything taught about it, never seen anything in manuals, can't recall it being discussed on dz before (other than how to hold toggles so it doesn't happen in the first place). I haven't, however, been to all of the various well known canopy control courses to see if they teach something. A test pilot could ask about handling an engine failure; that wouldn't imply he has no knowledge about the matter. I'm here to learn too.
  18. You are dismissing the fact that the ideas put forth by Bill and Lisa have mandatory training He's not necessarily dismissing it; but just looking at one part of the equation. In any case, people may have different thoughts about: a) mandatory wing loading limits, and b) mandatory canopy training. It sure is tough to predict how large effect of changes will be for the the less direct effects. If someone with 2000 jumps dies in a swoop, would he have avoided that had he been more limited in his downsizing progression? We'd have to know his exactly number of jumps and canopies to even decide whether to put him into some category of downsized too fast vs. not too fast. (Other than some sort of tautological "he died swooping... therefore he downsized too fast.")
  19. From when I was looking at everything dactyl related in Poynters, I noticed that the Jim Handbury design shows up under not just Advanced Air, but Guardian, and Pioneer too. From a personal contact, I was told that Handbury made a trip east in '76 to Pioneer and Parachutes Incorporated, to negotiate with them and/or show them how to build Paradactyl's under license. To what degree Pioneer actually built dactyls, I have no idea. All this suggests that it is possible that you have a Pioneer dactyl. Let's hear more about it!
  20. Your crash is certainly a well known nasty one, DSE. A reminder to people that bad things can happen even "just" doing a front riser 90. For my own dropped toggle experience, my hand was already off the rear riser, so it would be hard to find again quickly. I had already planed out on rear risers, so I didn't have much time, but on the other hand at least I was already low & fairly level & not simply in a high speed dive at the ground. I didn't try to grab any particular thing down low, like finding the toggle or the riser again. I reached high, sweeping an open hand forwards, because then it should connect with SOMETHING relating to the rear riser's lines. Whether by luck or good hand placement, my hand hit the steering line above the guide ring. Hooking my fingers, one finger caught the brake line securely, and with that I pulled hard out and down. Trying to get a good grip on something to pull straight down would be harder and take more time, but an outward and downward pull doesn't need a grip. It was a bit of a skidding landing, but hauling on the brake line above the brake ring was enough to stay reasonably level and unhurt on the little Cobalt 75 at 2.3 loading. The technique might not work well if say you were able to catch only the very outer most C line. But other than that, I figure if you don't have the time to re-grab exactly what you want, sweep and hook your hand onto something rear-riser related to yank out and down on, so you aren't doing a totally one-sided flare.
  21. Still, a given size of gust will cause a lower change in angle of attack for a wing at higher speed. In that sense one can 'cut through' turbulence -- less likely for a down gust to unload the front of the wing and collapse it. On the other hand, more speed gives less time for the canopy to adapt to a new angle of attack and thus can 'get hit' by turbulence if flying faster instead of having time to react and adapt to the new conditions if flying slower. Which could be good or bad depending on the situation. (Eg if you get hit by some idealized upwards gust before hitting a following downwards gust -- the down gust isn't as extreme a change if the wing hasn't already reacted to the up gust. In that particular situation, more speed is again better. But if it is a down gust followed by more down gust, the wing moving with the conditions can be better.) I think it will depend on the exact natures and scale of the turbulence, which factor wins out. Still, I think extra speed tends to win out as better. (At least as long as one doesn't actually have a collapse -- then slower can be better in many circumstances.)
  22. clicky http://www.ebay.com/itm/1963-U-S-MILITARY-ISSUED-PARACHUTE-WITH-UNCUT-LINES-/140724084588?pt=LH_DefaultDomain_0&hash=item20c3cf1f6c Yeah, that it one super modified C-9! I've heard a couple times on dz about people doing mods like that, but only as a personal rigging project.
  23. FWIW, video doesn't show the jump itself. They cut when he's just starting to launch. One does get to see the preparations though.
  24. Clearly a good answer, and one that can apply in many cases. Flare with the toggle, not too abruptly, so that one can try to follow through on the other riser to stay level or nearly so. I was mentally focusing on a worse sub-set of the possible dropped toggle situations, where the toggle is lost as one lets go of a riser, so that one is faced with having nothing in that hand at all. .
  25. "What do you do if you drop a toggle as you are about to flare?" I have never heard any discussion about contingency plans for that issue (although I haven't been to any canopy control classes). So I'm curious what comes to peoples' minds or what they have practiced in the past. Clearly it is a situation best avoided in the first place through good procedures, so that for example the toggle doesn't come out of your hand when transitioning from front risers or rear risers. I've got my own ideas, which I put into place one time when I dropped a toggle. It's not like the ideas are all that difficult to figure out, but I'd like to see what others think before offering a suggestion.