pchapman

Excuse me, I meant "reasonable" in that the explanation is not implausible. I can believe the physics of it, that this might not be uncommon for pyrotechnic cutters in general, that occasionally some residual current leakage can occur, so that a simple open/closed circuit check will not always immediately discover a fired cutter. I haven't checked the manuals in detail, but for example the couple Cypres 2 manuals I checked don't promise any given readout after a firing. (Although 1111 or 2222 "may" indicate a fired cutter.) The skydiver community (and Airtec) has generally assumed that one doesn't need to have a readout to tell if the loop was cut -- if the container isn't open, there's a problem with your container or rigging. Nevertheless, everyone expects AADs to do good startup error checking, and that is in the manual. ("CYPRES has fail safe-error detection") So in that way, the situation is BAD. A startup self test essentially FAILED to find that the AAD was non functional. Startup tests are supposed to be reliable; this was NOT! However, this is a pretty exceptional situation -- it has been very very rare that people have landed and packed and not noticed they set off their AAD. There's only danger if the Cypres cutter fails to cut (which it never seemingly has) or the gear is bad. Still, it is bad for Airtec's image, promising one thing, and delivering another. If they had at least mentioned this in the manual, people might say that it is totally inconsequential in practice. Whether they liked that behaviour or not, at least it would "be in the manual."

Play with it on the ground. Pull the kill lines out, ALL the way. Look for the little tabs of line that stick out from the kill lines, that will catch on the slider instead of sucking back into the slider. Sometimes those tabs get bendy and soft over time, and don't catch well, but they can be given more stitches or have the mouth of the kill line channels narrowed a little. Edit: Figure out how things work on the ground before trying them in the air.

That's another completely reasonable explanation from Airtec, which is good, but again it is one of those frustrating things they don't seem to tell you about -- "we know better, just trust us, you don't need the details".

The policy at the DZ I'm at is 8500', just to be consistent, even though it is somewhat arbitrary. But the point is to inform the student and let them choose whether to go for it or come back another day. Once (before the policy) I did go from 6700' on a day that was so hazy it was turning IFR.

What I meant about the TSO production thing is that at first look is that there are two somewhat separate issues. A company might be the legal owners of a TSO but not have an authorized production system to produce that TSO'd part. If a company has an approved production system, does it apply to all products under the TSO? I would guess not, but don't know. For example, UPT will have a decent system in place for Vector IIIs. But does their production approval apply to original Wonderhogs too? They shouldn't, if they don't have all the original hog templates readily at hand and properly labelled, with production instructions, or whatever would satisfy the FAA for production authorization. Your points are interesting about how "the new Company has absolutely no responsibilty to the old TSO holder or equipment or parts manufactured by that entity." If the company has no responsibility, is that just about liability for products produced by the old company (a big concern if you have looked into buying a TSO!), or does it involve "manufacturer's instructions" in any way? For example, I can see that it might be difficult to sue Mirage Systems for a failure in a 2 pin Mirage built by The Annex or National Parachutes or Sky Supplies or whomever did so. The company is a different legal entity. But, if it is all on the same TSO, can't Mirage Systems make rulings on 2 pin Mirages? We know the whole bit about riggers following manufacturers' instructions according to the FAA. If Mirage System disallows (or allows) the Argus in their rigs, is that for all rigs under the TSO, or only the ones that particular company made? Is Mirage Systems allowed to amend the packing instructions for the 2 pin Mirage? Or can UPT do the same for the original Wonderhog? And is the situation different if one company acknowledges the old gear, and another doesn't? You can find the hand written Wonderhog instructions on the UPT site. While I haven't checked, I bet you can't find any 2 pin Mirage packing manuals on the Mirage Systems website. You've provided useful information about the legal situation but I'm still trying to understand who may or may not provide "manufacturer's instructions" on older rigs.

But I'm wondering if that's more a PRACTICAL issue than a LEGAL one. The new company may or may not feel they are responsible, or care about outmoded rigs that almost nobody jumps. Would the responsibility still not legally stay with the TSO holder, rather than disappear if there was a change of company? I would guess that the company's word still holds, for rigs old and new, so then it just matters how things are worded. If Mirage Systems says you can't use an Argus in any Mirage, that probably applies to any Mirage under the TSO, 1 pin or 2 pin. If they were to put it only into the Manual for the 1 pin Mirage, then it would only apply to the 1 pin Mirage. That's a bit different issue than TSO production authorization as you addressed in a post after the one quoted above. Interesting topic of discussion.

The Vigil is adequate and commonly used. If you want lowest overall cost (as you strongly imply by your original post), go that route. If you want best quality, when it comes to firing when it should and not firing when it shouldn't, Cypres is still the best, at a higher cost. Despite all the arguments out there, and problems with all AAD's, whether real or suspected, it is pretty hard to dispute that breakdown of Vigil vs Cypres.

Hallo, Uwe, If you want to jump old style gear it is probably easiest to find an old Paracommander and get it back in the air. They are somewhat rare but are in peoples' closets, and are inexpensive since not in great demand. I'd be surprised if Pioneer wanted to sell to the civilian market any more. Instead of assembling to an old harness with a belly mount reserve, one could modify a more modern student or accuracy rig to fit a ParaCommander in a bag (rather than a sleeve). Then the whole gear isn't vintage, but with 3 rings, throw out pilot chute, and a deployment bag, it makes it all so much easier to use.

Thanks Uwe - here's what I found for the RZ-20 jump: http://www.youtube.com/watch?v=lWEEsoXRCBA

I dunno, ten years easy, in some cases almost indefinitely, subject only to the degredation of the materials involved. That only works if no outside influences have caused problems ... which is why we inspect things more often. Like elastics on a round canopy's diaper, or, very slowly, breakdown of the nylon. Any loss of PC spring strength would be slow but I wonder how much creep there might be. I've pulled old round reserves out of packs that were in there 10-15 years, that seemed good to go. Maybe the MA-1 was pretty weak but they always seem that way compared to modern PC's. And without a diaper there were no elastics to decay. As for safety stows in modern rigs, one sees 10 year old ones still in rigs, that aren't falling apart more than usual. Others, though, get pretty stretched out, but probably will still work since the fabric holds the stow together. I'm not sure how much difference there is, between a rig that has sat for 10 years packed, vs. one that has been in use for 10 years, and only unpacked at 120 day intervals for less than 2 hours at a time. I wouldn't trust anything "sticky" as much over time. Like ZP mains that we know can become somewhat brick like. Or the gummy inside of some Javelin freebags. High humidity can of course be an issue, with rusting hardware. Not sure how bad mildew on nylon would be. It doesn't supposedly eat the nylon itself, but one wonders what the effect would be over time. They pressure pack military canopies and airplane recovery parachutes for 5+ years and expect them to work. Not sure about how military ones are sealed. For BRS canopies for ultralights, those in sealed canisters, or fabric canisters shielded inside an aircraft, repack intervals are 6 years. That's down to 1 year if it is a soft pack outside the aircraft (and even then it should be protected from moisture etc). So the number of safe years could be quite long, but as the time grows, there are more and more caveats about how it was stored and problems that might occur with specific components. Simply having layers of nylon fabric pressed against nylon fabric, I'm guessing that isn't much of an issue.

I'd like to clarify that in billvon's example of opposite direction lower winds, the equation itself isn't failing. Nothing wrong with the math, as long as one allows winds to be positive or negative in magnitude. But in practice, it may be easy to miss that the lowers are from a different direction or have shifted, giving lower separation than typical for a given ground speed seen from the aircraft. (Naturally if the winds are not all in line, then one gets into vectors and components of the winds along the jump run. The simple form of the equation is no longer sufficient.)

Sorry, I hope you're joking, otherwise it's all wrong. The speed one is going creates no momentum effect at all. The plane will turn just as quickly whether it is going upwind or downwind. If I'm walking around in an airliner while doing 600 mph, I don't have any problems with the massive momentum either. Your plane will always be exposed to 30 mph of relative wind, before, during, and after the turn.

Another laugh is when someone suggests that to get back from a long spot, you want to spread your body wide, to catch air, because the wind is at your back. And, DigitalDave, don't know if this helps: When in freefall, after some time has passed after exit, you are moving with the block of air you are in, drifting with the wind. So you may be in a neutral body position by moving over the ground at the speed of the wind. It doesn't matter whether it is moving 5 mph over the ground or 50 mph. So when you open your parachute, the wind starts off hitting from directly below, whether you are facing upwind or downwind or any direction. The inflation how the canopy starts to fly are unaffected by the wind. (This all changes slightly when there are changes in the wind at different altitudes. Then issues of drag & inertia come into play, but in most cases, wind shear will have little effect. One has to understand the situation with essentially constant wind first.)

I'm just saying the direction one is facing relative to the wind isn't the deciding factor. If it keeps you in the right spot for lift, OK, but the points made earlier in the thread still apply, that facing into or out of the wind wasn't going to change the climb rate. You might as well argue that walking backwards can make your heart stop. Um, I'd say, that's wrong. Yes it does, someone says, your heart will stop if there's a cliff behind you and you walk off it. I'm saying, that's not the point, and not a consequence only of walking backwards in normal conditions. At least we are probably arguing only about how ideas are presented, not the physics of it. I think.

In which case the direction you are facing still has ZERO direct influence on the climb rate??! One's location in a region of wave lift or other form of lift obviously will change ones climb rate, and one may choose different headings to fly to or stay in the areas of best lift, which may or may not stay still in relation to the ground. But the heading itself still has zero influence on climb rate. (Nor are we here talking about dynamic maneuvering, or dynamic soaring, taking advantages of inertia and shear layers. That's a separate conversation.)

Maybe then we just need a short list of caveats to be added to the spreadsheet. Something like: "Do not use table, and consult DZ management if: 1. Jump run is not upwind, 2. ...." It's common enough for math to describe a real world situation accurately enough, but only within certain boundaries -- and we often forget those boundaries and assumptions.

As others are saying, one can't tell without video & talking to everyone involved. But one expects some specific reasons for not moving on to the next level, to be written in your logbook or a student record kept by the DZ. So it is hard to believe you had "no issues whatsoever". But I could believe situations where the deviations from ideal weren't big enough to prevent moving up. Normally it is a bit tough to explain to students why they are being held back to pay for another expensive jump, so as an AFF instructor one wants to have a pretty clear reason --- "The requirements for this level include xxxx. You were unable to complete xxxx with any stability." How might instructors be imperfect? It is possible for an instructor to be overly picky. For example, not passing someone on Level 1 because their pull was slow and despite altitude awareness in general, the pilot chute release was 500' low. (I don't know how good an example this is, because I'm newish at AFF instructing myself.) Technically perhaps a fail, but in the big picture the essential tasks were completed to move on. Occasionally, more junior instructors might unintentionally hold a student back a bit, by not releasing the student as much as planned on a particular dive. The instructors are a little wary because of something that happened before, but at some point the student has to be let go more to show what they can do, if they are to fulfill the tasks for the dive.

Techically that's basically right but it is wrong in the conversation here. In skydiving and aviation, there is only one basic definition of aspect ratio for a wing. If you want to talk about some other aspect ratio, you'd have to be very specific that it is the aspect ratio of something else. (e.g., the aspect ratio of the cell openings)

Keep digging. Good luck, you'll need it. It is indeed a pain as an instructor if novices think they know a lot about things before getting proper instruction. If a novice gets obsessive and starts practicing techniques without understanding the details, it makes it tougher to untrain them later. So anyone asking questions here about basic techniques gets shot down and told to ask their instructor. Yet in other activities in life, one is allowed to read up first. If I wanted to learn to sail or motorcycle, I'd hate it if those who knew how to do those things, acted as if the techniques were all the private rituals of a secret society... So, are there any good summaries out there? The Canadian Sport Parachuting Association doesn't have their basic freefall skills manual (PIM2A) online for nonmembers. The British Para. Assoc has some manuals online for canopy flight and more advanced freefall skills, but not the basic stuff. The USPA's Skydivers Information Manual is online but is huge and perhaps a little baffling to a novice. Lots of good info but not designed to teach the basic maneuvers without an instructor around. Well, there are the previews of "Parachuting: The Skydivers Handbook" in google books: http://books.google.com/books?id=1jDqpK2HlxYC&lpg=PP1&dq=parachuting%20the%20skydivers%20handbook&pg=PA192#v=onepage&q=parachuting%20the%20skydivers%20handbook&f=false You can probably get some useful info from that, even if parts of it seem to be a little dated.

As Phreezone said, keep the rig for someone who wants to do vintage canopy jumps. The harness is built differently for 3 rings, and PC's are huge compared even to student or accuracy canopies, so if you want to jump (after appropriate training), just buy some cheap used equipment (under the advice of a rigger or experienced jumpers). You'll get all sorts of cool advantages: single point 3 ring release, hand deployed pilot chute, square reserve... (Yours must be a relatively slim rig, for a PC in a pod rather than in a sleeve. Didn't the Parasled pack up even bigger than a PC? I still have to get mine into service.)

Welcome aboard! You're in the appropriate Intro & Greets forum. Those who jump old stuff tend to hang out in the History & Trivia forum, as well as those who who actually experienced the old days. It wouldn't be inappropriate to post there if you had some tales to tell of your days of jumping. Start a new thread for general tales, or if there's some old thread where a very specific response would be appropriate, one can resurrect those, even if they were last posted to a long time back. (Eg, there have been a couple Para Sled threads over the years.) (Use the search function at the bottom of the screen, if one wants to search just the forum one is in, or pick "options" to pick a particular forum). Vintage canopy jumpers are rare in any given area, but there are some around. Vintage canopy buffs certainly do take donations of old equipment or will buy them at a small price to get the stuff back in the air. I can get you a few names, but they're scattered across the country like in Arizona or Texas. I can see that you'd be most interested if you someone who would get the gear in the air again in your area. (Contact screen name "Amazon", she may be in Washington state, and has jumped rounds in the last decade, but I'm not sure that she's active with that.) I've got a couple ParaCommanders myself, a Paradactyl, a UT-15, etc., all jumped in the last few years.

Around here there was the jumper who had his car broken into and his gear stolen. Some time later a guy signs up for the first jump course at a local DZ... and shows up in a skydiving jumpsuit. Gotcha!

I won't go into the critique that's certain to be coming, regarding what you've learned so far about the role of barrel rolls. But I'll say: Barrel rolls can be useful when one has planned a dive where the skills are lacking, everything goes to shit, and people are all over the sky. But ... when one can plan dives with appropriately skilled people, and everyone follows the rules even if things don't go perfectly, then amazingly the need to barrel roll pretty much goes away!

Openings at different altitudes or premature openings shouldn't actually complicate the spotting issue much, even if it complicates my afternoon in spending time thinking through the scenarios. I haven't thought it all through but: Usually it won't be a problem. Someone opening their canopy will be driven away from the drop path of the next jumper, whether opening high or low. See the first drawing (with 3 example). When viewing the drop from the side, there will be a sharper angle of drift when under canopy than in freefall. So someone in the first drop who opens early, will always drift away further from the path of the second drop. (Eg, a freefaller at 120 mph in massive 80 mph upper winds will be about 33 degrees from the vertical. If he opens, he'll be drifting downwind at an angle close to the horizontal in those winds.) The wind effects will already have been taken care of, as long as the winds are close to the uppers vs. lowers as entered into the calculations. Even if the lower winds extend higher than expected, both the first jumper with a premature opening, and the second to jump, still in freefall, will still be in the same lessened winds together so there won't be any loss of separation. About the only problem I see is if the actual winds don't correspond to what was plugged into the equation. For example, if ground speed is near zero, then one gets opening separation only from the lower winds. If they suddenly die, you'd drop people ontop of each other. When in the aircraft, one can tell what one's ground speed is (to some degree), but one can't tell what the winds are actually doing down at 2000'-3000'. For the formula to work you still have to get the winds right - garbage in, garbage out. If you are counting on the winds at opening altitude to provide a lot of the separation, be sure that those winds really are there! =========================== As for the issue of different freefall time of exposure, i.e. belly vs freefly, that's largely a separate issue. But can that lead to loss of separation despite "doing things right" in terms of accepted exit order? Let's look at one possibly scary scenario, with freeflyers following flatflyers, beating the flatflyers to the time of opening, and then drifting downwind towards the flatflyers. It turns out not bad at all, despite initial fears. The scenario: Flat flyers exit (time = 0), then freeflyers, as normal, say at t=7 seconds. The two drop paths diverge, increasing separation, as normal for a slower falling group followed by a faster falling group. I don't think it matters much what the winds are in this scenario. (Obviously the exit timing of 7 s was picked for some particular typical winds scenario.) Although the freeflyers exit 7 seconds after the flatflyers, they race head down to opening altitude in 40 vs 60 seconds, "getting ahead of" the flat flyers by getting lower then them at the same time. The freeflyers open, at second #47. They have 13 seconds to drift down wind until the flat flyers open, at t=60. Isn't that cutting down on horizontal separation? In normal circumstances it isn't actually that bad: Even at t=60, the freeflyers will only have been exposed to the wind for 53 seconds, so they won't have drifted back the same amount as the flat flyers have in their 60 seconds. So they still have more horizontal separation than between exit points. Also, as soon as the flat flyers open, they also drift downwind quickly. There is one way in which this scenario can get dangerous: if those under open canopy don't behave themselves and fly down jump run immediately, putting themselves closer to the flatflyers about to open. But that's part of a common hazard in many jump run situations: If someone opens before someone else (for whatever reason), he'll create an increased hazard if flying in the direction of where someone is still in freefall. So the hazard isn't unique to flatflyers followed by fast freeflyers. So I've shown some ways in which the "groundspeed plus wind at opening" method still works despite trying to foul it up in various ways, plus mentioned a couple caveats. Anyone got a better insight into what sort of situations might make it fail?

I didn't include the photo of the data panel on the sensor originally, so here it is. I'm resurrecting this because there have been questions about the sensor used by Airtec. It is the XCX 15AN, at least at that time. Edit: The Honeywell product page is at http://sensing.honeywell.com/index.cfm?ci_id=140301&la_id=1&pr_id=151532, from which one can access info on many of their pressure sensors. Data Instruments is now part of Honeywell.