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Everything posted by mxk

  1. I was subscribed to a number of topics on the old forum and none of those subscriptions were migrated over as followed content on the new site. Is that intentional or an oversight?
  2. Anyone know if US-based Vigils are still being sent over to Belgium for maintenance? I was told back in April 2017 that they will soon do all maintenance in Florida.
  3. The actual teardown begins at 9:26. CYPRES 1 teardown, if you're interested:
  4. The most important case when the RSL would be pulling super hard is when it's still attached to the rig (i.e. AAD fire or straight-to-reserve deployment). I can see the fold-in-half scenario happening for an unconscious jumper falling on his back. AAD fires, RPC launches toward the red end and wraps around the body, bridle doesn't have enough time to rotate. The pull of the bungee in the center not only applies extra friction, but also causes the assembly to fold in half.
  5. I think this falls in the "know yourself" category. Figure out what your goals are, what disciplines you would be interested in pursuing, and go from there. It's definitely true in my case. I bought everything new four years ago with about 160 jumps on student gear. I thought I would downsize from my Spectre 230 within a year or two, but the more I flew it, the less I felt the need to do so. Demoed a Storm 210 last year, which didn't do anything to change my mind. Still very happy with my rig at 830 jumps.
  6. I'd like to see this test performed in the opposite direction. Hold the assembly as it would be held in place for a straight-to-reserve deployment, and show what happens if the PC launches in the direction of the two arrows (as close to 180 degrees as possible). How does the extraction force change? Also, that's a large amount of fabric that has to be kept flat in order for the disconnect to happen as shown. If it gets folded in half, which seems likely to happen with the RSL attached in the middle, the disconnect force will go way up and may lock the assembly altogether.
  7. Follow other industries and add buttons that do nothing, but make the user feel better.
  8. Indeed. I was on a low pass load yesterday with nine other people; five experienced jumpers, four doing a B license canopy course, and me in a wingsuit at the back. Red light goes on, door opens, red light goes off, and seven people jump out before I could ask the pilot why there's no green light. Everyone assumed that the light was broken. In reality, the pilot just didn't move the switch to the correct position. Only three people exited with the green light on. I fully expected to have a conversation about this with the pilot, DZM, and all jumpers on the load. To my surprise, no one said anything at all on the ground. It wasn't as if people didn't notice either. As I was zipping up my wingsuit, I heard those by the door saying that the green light was off, and then jumping out anyway. People seem perfectly happy interpreting the lack of a green light once the red goes out as a broken bulb or pilot error than as a command to stay in the plane. This was also the first load of the day, so I guess the lack of evidence that the bulb works was also a contributing factor. I would say it's classical conditioning of red-green-jump, red-green-jump, done over hundreds/thousands of skydives, but it seems to affect very experienced, as some on my load were, and newer jumpers alike. Furthermore, once the first person goes, the next one is less likely to stop and think. Mistakes were made, fortunately no real harm done, good lesson for the future not to fall prey to wishful thinking.
  9. Where did you get those numbers from? Here are the actual recommendations from current manuals: Curv: 18" Infinity: 15-18" Javelin: 12-18" Vector: 15-20" Wings: 12"
  10. See this thread. MLW measurements vary between manufacturers and may depend on other measurements, so the numbers posted in this thread aren't comparable without that information. "Strapping on the 16 and risk getting hurt" shouldn't be one of your options. Put the rig on and have an instructors evaluate the fit. Alternatively, send the container serial number along with your measurements to the manufacturer and they will tell you whether it will fit or not.
  11. There don't seem to be many examples of how not cutting away the main first made the situation worse. There are a lot of examples of the opposite. My own rule is that unless there is tension on the main risers, I go straight to reserve. I can't think of a single good reason to do a preemptive cutaway that doesn't have the immediate effect of detaching the main in a somewhat predictable fashion (i.e. there is tension on the risers and you have some idea of the direction in which the main will go when that tension is released).
  12. At my previous job, I spent over a year developing a data collection platform for Tizen, which would stream sensor data to an Android phone. Everything you said is pretty much spot on. To be fair, Gear S2 and S3 added native app support, so you can implement your stuff in C or C++, which I had to do to get access to the more advanced power and sensor APIs. It was still a nightmare though, especially with each firmware update breaking different APIs. So glad that work is behind me now.
  13. I tried corded Moldex, didn't work (couldn't pull the plugs out), and didn't like having the cord. I've been using cordless Moldex Sparkplugs pretty much since finishing AFF during all phases of the jump (except for CRW where I take them out just before exiting). Never had any pressure-related problems. I'd be interested in any stories about situations where hearing under the canopy was directly responsible for avoiding an incident. I'm sure there have been a few cases, but overall I think the benefits of hearing under the canopy are greatly exaggerated, and by no means balance out the damage done during freefall (if you don't opt for the coded solution).
  14. The problem we're trying to solve is to prevent an opening shock going above some number of Gs. Tapes and webbing break at a certain number of lbs. For the same limit in lbs, a 5G shock for a heavy jumper would be a 10G shock for someone half the weight. The first one might be ok, the second one might be fatal. An AAD could measure Gs, but the measurement might be delayed or underestimated because the sensor is not attached directly to the MLW. For calibrated tape/webbing solutions, you'd need different breaking strengths for different jumper exit weights, which means many more variations in riser manufacturing. I keep asking UPT to build mini risers with standard rings, but they keep saying no.
  15. Exactly. That would be more of a poised exit. You said Mr. 15K jumps didn't explain why. That makes me think he doesn't have a good reason. All the advice I dispense comes with the reasons why it's "good advice". he said because it was faster to get down to the formation. It seems to me that there might be some truth in this with respect to reaching terminal velocity faster. If you exit in the direction of flight in a head-low attitude, your body effectively becomes a wing at a negative AoA, meaning that the relative wind will be pushing you down. This is particularly noticeable in wingsuiting. With FS, this effect won't last very long as you lose forward speed, but you should still reach terminal velocity a bit faster than if you exit head-low toward the back of the airplane, where you'd experience the opposite effect. Of course, for you to benefit from this, you'd actually have to maintain your heading for a few seconds instead of flying back to your formation, so I'm not sure of an actual net benefit.
  16. I'm not entirely certain of what pattern you were flying, assuming this was at Orange. Left-hand to the east and ended up landing short north of the hangar (next to the parking lot)? If so, then yes, you should have turned much earlier. Regardless of the landing direction, it's a very long field. Some people will land closer to the hangar on one side of the ditch and others closer to the peas, so your target will determine your overall pattern and base turn. There is no way you would have caused any issues for the other two jumpers if you turned just past the ditch while they continued beyond the hangar (that's what the situation sounds like to me, but please correct any wrong assumptions on my part). Trying to avoid others is good, but not at the cost of backing yourself into a corner where you no longer have any outs. That usually means changing your plan earlier rather than waiting to see if the current questionable situation will resolve on its own. Try to anticipate what the others will do and adjust your plan so that you don't end up at the same place at the same altitude at the same time. In your situation that might have meant turning to base earlier, flying a longer base leg, and landing on the south side of the field, or possibly flying a short base leg and extending your final. Especially while you're still learning what your canopy is capable of in different wind conditions, leave yourself extra margin of error for both overshoot and undershoot situations.
  17. That's where even a low-resolution GPS would have been useful. Upload local topology data to the AAD and have it automatically figure out the elevation directly below you regardless of the take off location To answer your question, CYPRES has a dropzone offset adjustment, which is reset after one jump, and an activation altitude adjustment, which is persisted. Vigil has an altitude correction function, which is persisted. If you have only one adjustment, it should be permanent until changed by the user. Adding a one-jump offset might be useful to those doing demos. I've never needed it.
  18. Mandatory for all II and 2+ units with affected firmware within the next two years or before the next jump above 27k ft.
  19. Lies, damned lies, and statistics. I'm not sure why this post ended up being so controversial. Wingsuit type should absolutely be reported. Helmet and any other gear should also be reported if it's relevant to the incident. I don't care that G3 is the most popular helmet. If it keeps showing up in head injury incidents, maybe the bad publicity will finally get helmet manufacturers to produce a helmet that actually offers some protection. When a helmet doesn't do it's job, that's relevant information even if everyone is wearing the exact same helmet model. It's not always about comparison with competition.
  20. Is there any one manufacturer that's known for good bootie construction? I have a Vertical Loose RW suit and the booties started falling apart at the toes after 70 jumps, even though I always take them off under the canopy. I put some reinforcement in those areas myself, which has held up over the last two seasons, but I'm looking for alternatives for my next suit.
  21. He also said that landing out is not an option . And the DZ policy of what to do when someone is landing in the wrong direction was not specified. People are assuming that the policy is to land with the tetrahedron, but that's not stated in the original question. There is a tetrahedron in this scenario, but because you weren't attentive during the DZ briefing, you can't remember what the local policy is. The first person is landing in the opposite direction and you have to make a choice of following them or landing in the correct direction.
  22. I'm changing my answer. If you're #2 and see that #1 is setting up to land in the wrong direction, spiral down and land first. Problem solved.
  23. Why?? That's the real issue here. From what I've seen, that's just how it usually plays out regardless of the what the local DZ policy is. Probably because no policy has been standardized across DZs. As long as everyone follows the same rules, there is no problem. But that's like saying that everyone should just land in the correct direction to begin with and we shouldn't even have any policies of what to do if someone doesn't. Enforcement is what you do after people land and, hopefully, walk away. It also doesn't do anything for visiting skydivers who come from DZs with a different set of rules. Strong enforcement of different rules will not prevent the problem from reoccurring. Until the rules are the same everywhere, the problem will persist.
  24. You cut out an important part of my quote, which was referring to tandems and wingsuiters. They are not going to follow the first person down. Tandems will land in whatever direction they want, and wingsuiters are landing with them. I also provided an example where the second follows first, and third follows second idea isn't going to hold. In answering the question, I said that I would follow the group of skydivers that will be landing at approximately the same time as I am. That's the safest course of action regardless of the policy. Unfortunately, that group of skydivers will usually have some people landing one way and some the other, so the real answer is that I would do everything I can to avoid landing "as a group." That means either creating vertical separation or landing elsewhere.
  25. The answers about following the DZ policy, while correct, are not helpful to discussion about whether one policy is better than the other. I don't like the "follow first person down" rule. Of the few people that I talked to after Safety Day, all agreed that following the tetrahedron was a better idea. Here's the basic problem. If someone doesn't look down at a fixed bright orange arrow telling you the landing direction, why would you expect them to notice who the first person down is/was and in what direction they landed? What if the first person lands in the correct direction, which you don't see, but you see the second person landing in the wrong direction? Are you now (incorrectly) assuming that he was following the first? But it's worse than that, because by the time you see their landing direction, you may already be committed to entering the pattern from one side or the other. So now, depending on where you were in the exit order, you're really talking about anticipating the direction in which they will land, and assuming that they won't change their mind in the pattern. Do we want people realizing half way along downwind that the first person landed the wrong way and then making 180 degree turns to follow them? Neither policy will fix the jousting, but one policy has much fewer variables and decisions that need to be made than the other. The change to the policy will also ensure that a significant portion of regulars who weren't at Safety Day will do the "wrong" thing this season. What would I do if landing elsewhere is not an option? First, probably sit in deep brakes as long as I can to build spacing. Second, try to anticipate what others at my altitude are about to do and follow them. If I manage to create enough separation so that people are either already on the ground or not yet in the pattern, I'm following the tetrahedron. At a certain point, you'll be closer to tandems and wingsuiters, and they aren't going to be following the first person down.