johnfallo

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Everything posted by johnfallo

  1. speculation is the correct word. How the release occurred? I think the cable housing was pulled. It could have been from the long side or from the short side above the mudflap. Given the position it was found in the aftermath I would be inclined to believe it had been pulled in that direction (above the short side mudflap). As to how it would have been pulled I don't have any idea. Some additional thoughts, While the jumper did change out his main a couple weeks earlier.The jumper is knowledgeable about his gear. I feel confident that he would have hooked up his 3 ring correctly. but lets say for arguments sake that he misrouted it on the long side, riser loop not through the terminal end grommet of the cable housing as in the picture I've attached. This configuration will stay together until pulled on, and it doesn't take much force to pull the housing away and release the cable and therefore the riser. Add to this that the long side isn't tacked under the mudflap, so if it somehow works itself out from under the mudflap it will tend to want to straighten out and viola you can explain the riser release. This type of release is very easy I don't think that this type of release would generate very much force downstream on the cable housing to move it at all. much less break the tacking and rip the housing out of the shrink wrap at the chest strap juncture all the way from the other side of the rig. What would move easily would move, and then you would have release. This scenario would explain the release but not the housing being out of position. once released there should be nothing pulling on the housing, and if pulled from the long side it should have remained extended past a normal length on the long side. Further all of this would have to be made on assumptions as there was nothing to indicate this. What was obvious and would also cause a RSL side release is what was present, the long side housing moving upstream independently of the cutaway cable and short side housing. I just can't figure out what would pull on it.
  2. I was not suggesting that at all. I just knew he didn't get before pictures. Pictures after are better than no pictures at all. I did look at the entire length of the cable where visible before it was packed and I didn't observe any damage or imperfections. I am not his rigger but was interested in what could have caused this. While I think I know how it happened I am clueless as to a cause. In a case such as this the more eyes on it the better.
  3. He did not take a picture of the other side before it was put back in place.
  4. There was no damage or wear anywhere along the path of the housing through the yoke of the rig. I didn't see any tacking or securing through the yoke other than a large tape loop which the housing runs through freely to keep it generally in the right area. The end of the long side (RSL side) was no longer under the mudflap, I did not see any indication that there had been any tacking or other securing method used on this side to keep it under the mudflap, but it did not appear to have been pulled since once tucked into the mudflap it was the correct length. It seems possible that the long side could have come out from under the mudflap in freefall or at deployment time. This still seems to me to require something pulling on this loop of housing hard to break the tacks, shrink wrap, and pull the housing around two 180 degree bends and doesn't explain to me why more of the housing wasn't coming out of the long side. I really don't see that housing getting pulled all the way from the long side and then after release when there is no longer any tension or compression on it, The housing then reverses to come 8-10 inches out of the short side exit hole above the mudflap. Typically I would think that the grommet in the terminal end of the housing would be enough to hold everything in place so long as there is no pulling action further down the line. The tacking and shrink wrap at the chest strap junction were the only thing I saw to prevent it from pulling through. If the housing had been pulled from the long side or anywhere above the short side mudflap it should have been constantly retracting. I get that if it stopped near the hole above the mudflap it may have poked out of it, Yes, the hole is 4 inches wide,but it is still only half an inch tall. but I still have trouble thinking that it would reverse the direction it was getting pulled to come out of that hole 8-10 inches. The bottom line is we need something pulling on that housing. It did not get there by itself.
  5. I am one of the riggers to look at this rig. here are my findings and opinions. Cable housing was tacked and cable housings were shrink wrapped together. Cutaway handle stayed in place, short side cutaway housing stayed in place. The long side (RSL side) cutaway housing was pulled out above the mudflap and protruding about 8- 10 inches. I know pulling that housing with the handle and other housing in place would cause the release, but I cannot understand how it got pulled from there at deployment time (or any other time for that matter). I have to push my finger into a half inch hole (where the short side housing exits to the big ring) and to try to wiggle my finger under the long side housing as it continues through to the yoke. this is where it was protruding from. I tried to do this after the rig was repacked and it's not easy. There is nothing apparent that could be close enough to do this. He had changed his main a couple of weeks before, but I can't think of any possible way that an inadvertent release of a misrigged 3 ring would pull on the cable housing once released, but if it were pulled from the long side it should have been retracting into the yoke, not protruding out from the mudflap, this appears to indicate it was pulled in this direction.
  6. johnfallo

    Exit Separation

    *Miss Melissa, I also try to teach my students how to gather the necessary information and the education to think for themselves - to use the winds forecast to make an educated guess about ground speed of the aircraft and therefore separation. I feel this is a good exercise. However, I feel it is inadequate in practice due to the many factors which can change the actual ground speed of the aircraft such as incorrect forecast, winds changing over the course of the day, jump run being flown not directly into the upper winds. Unfortunately many jumpers are not interested in doing math when they arrive at the dropzone, especially some of the more experienced jumpers. With 23 people on an otter load, I do not want those I care for relying on someone's best guess of conditions that may have changed, much less the jumpers that don't bother. The key is getting ground speed from the pilot after the cut every load. This information is right in front of him on his GPS. It is the only accurate way which takes into account any changing conditions or off heading jump runs. You stated it very well in your Blog post, "Seconds Count." That statement couldn't be more true. As in my first example, the 2 extra seconds called for could have made the difference between having some fun and two jumpers having a very bad day. Most jumpers will do what is asked of them to insure safety. The rest will comply if it is a matter of policy with consequences. Without a policy and everyone on board we will just be waiting for the next incident. Last weekend we had a 23 knot ground speed at 14,000 feet. There were 20 jumpers on the otter, multiple groups and each group gave 30 seconds with no go-around. No one had any trouble making it back to the dropzone.
  7. johnfallo

    Exit Separation

    To the 45 degree rule people: we all probably prefer to employ the methods we learned first and are most familiar with. That doesn't always make them the most reliable methods. The article ( http://www.dropzone.com/safety/Exit/Exit_Separation_Revisited_628.html ) which I linked to near the end of my article goes into far more technical detail than I wanted to get into as to why the 45 degree rule is not a reliable method. I wanted to keep things simple and accurate for all levels of jumpers.
  8. johnfallo

    Exit Separation

    On Saturday October 26, 2013 there was a near canopy collision by experienced jumpers. There were several factors which may have contributed to this event. I feel that a lack of understanding of exit separation was a major contributor. The winds of the day were posted: 24 knots at 12,000 feet, 22 knots at 9,000 feet and so on. I was on the first load, first out with a three way formation. I turned to the group behind me and asked for 10 seconds of separation. The response was “Why? That’s a lot of time.” Both of these jumpers have around 500 jumps. One has been jumping for over 10 years, the other for 9 years. One of these jumpers was part of the group that was involved in the near collision later that day. The incident: a near miss at opening time between two skydivers we will call jumper 1 and jumper 2. Jumper 1 left the plane first as part of an 8 way relative work group. Jumper 2, as part of a less experienced 2 way relative work group, left next with 5-6 seconds of separation. The second group left the plane flipping and having fun then got stable and continued a normal relative work dive. Jumper 1 was oriented to track up the line of flight decreasing his separation from the 2nd group. Jumper 1 further decreased his separation from the 2nd group by continuing to fly his canopy up the line of flight for 12 seconds. At which time he noticed one of the jumpers from the two way open pretty close. He then started looking for the other jumper from the two way group (jumper 2) and started a right rear riser turn. At this point, jumper 2 under a still deploying main fell past and within 20 feet of Jumper 1. Here is a link to the video of the opening sequence. This video was taken with a gopro camera and the jumpers in it are closer than they appear. Conclusions: 1. The initial flipping on exit of the second group may have had the two way in an orientation to slide down the line of flight and therefore contributed to the second group moving towards the first group. If so this would have been only momentary and not a large contribution. 2. Jumper 1 decreased separation by tracking up the line of flight. Although a contributing factor to the lack of separation, this was an appropriate action as on groups of 2 or larger all jumpers should track away from the radial center of the formation regardless of whether that puts them tracking up or down the line of flight as this will give them the greatest amount of separation from the members of their own group which would pose the greatest danger of collision at opening time. Jumpers tracking up the line of flight away from larger groups should always be aware of their direction and not “over track”. 3. Jumper 1 was flying a small fast canopy, continuing to fly up the jump run, holding into the wind with his brakes still set. This decreased separation with the following group. Every skydiver should know where jump run is planned to be before boarding the aircraft. All jumpers should upon opening orient themselves as quickly as possible to fly perpendicular to jump run at least long enough to ensure the groups before and after them have opened. 4. There is no question that mistakes were made on both sides, but there should also be no question that there would have been greater separation with 8 seconds at the door as called for in the chart below. In this case an extra 2 seconds separation would have equated to between 224-252 more feet of separation. We are also reminded of another incident we had a while back. Jumper 1 on a hop-n-pop leaves opens and flies up the line of flight. Jumper 2 leaves with about 5 seconds of separation and tracks down the line of flight. Jumper 2 tracks through Jumper 1’s canopy ripping it in half. Luckily neither one was injured. Another example is the video posted Iloveskydyving.org. This video clearly shows the following group giving 8 seconds of separation. Judging from their flying style it is obvious they are very skilled and not likely sliding through the air unintentionally. However, they still end up opening dangerously close to the group before them. We don’t know about what mistakes the group ahead may have made if any, but consider the problem may have been enough wind to dictate more time for adequate separation. Close Skydive Canopy CollisionAs Jumpers, we must have a basic understanding of the effects the ground speed of the aircraft has on the amount of time that we need to allow for the same amount of separation. I have heard swoopers say that the only good wind is no wind. They are saying this because in a no wind situation all things remain constant and consistent. Likewise at altitude if the aircrafts speed relative to the ground was always the same we would always give the same amount of time for the same amount of separation. What is adequate separation? In distance, the number I was taught is 1000 feet from center of formation to the center of the next formation for small groups. This number increases up to 2000 feet or more for groups of 8 or larger. Consider two 4 way groups lined up perfectly with jump run which will result in a jumper from each group tracking directly at one another. This allows each jumper to track 250 feet with 500 feet still left between them. The Skydivers Information Manual goes farther and recommends 1500 feet of separation for small groups and solos. What is adequate separation? In time, that will depend on the speed of the aircraft and the wind the aircraft is encountering. In other words, it will depend on the ground speed of the aircraft on jump run. See the chart put together by Phil Litke. These numbers should be considered minimums for 1000 feet of separation to be doubled for following groups of 8 or larger. Here are some examples of experienced jumpers and Tandem instructors giving between 13 and 31 seconds exit separation when the winds were very high. Also consider that these instructors are, for the most part, giving such separation on solos and 2 ways. As stated earlier, larger groups should be allowed more distance and therefore more time. We are all concerned about hosing the guys in the back of the plane by taking too long. I am not advocating that we give more time unnecessarily. If the speed of the aircraft dictates a certain amount of separation between groups this should include your set up, climb out, and count. I am not suggesting anyone taking longer than the conditions call for as this would create different problems such as people landing off, unnecessary go arounds, and wasted fuel. Most of us have had experienced people in the back of the plane yelling for people to hurry up and get out. This is because they feel you are taking too long to exit and will end up with them getting too far from the airport to make it back. If the winds are strong enough to necessitate a certain amount of separation then likewise the plane is moving slower relative to the ground, Freefall drift will be greater, and the acceptable opening spot may be farther from the landing zone. Every skydiver should know the acceptable exit and opening points for the conditions of the day. Many people land out without trying to make it back because it looks father than they are used to seeing. Without looking at the winds and calculating the opening spot before you go up you have very little chance of knowing for certain whether you will make it back, especially as the winds get higher and the spots get longer. One thing that you cannot control when you leave the aircraft is what the group behind you will do. We all should look after each other. By knowing how much separation to give you are looking out for yourself and the group ahead of you. Don’t be afraid to confirm with the group behind you that they will also wait an appropriate amount of time before exiting. Recommendation to reduce the likelihood of these type incidents: 1. Phil Litke’s exit separation chart should be posted near the jumper closest to the pilot for easy reference on jump run. 2. Upon turning onto jump run after the cut, the pilot will inform the close jumper of the aircrafts ground speed. This close jumper will look at the chart and determine how many seconds are needed. The number of seconds separation to give will be passed down to all jumpers on the load. 3. If this turns out to be too great a burden for the pilot we should install a GPS unit near the door so that the jumpers can determine ground speed themselves and make all jumpers on the load aware of how many seconds separation to give. We all have to get on board for this to work. Our landing direction at our dropzone is mandatory. This has been the best proactive step towards promoting a safe landing area and smooth landing pattern I have seen since I have been with my dropzone. The chaos of 22 jumpers landing in every direction in light and variable winds seems to be behind us. Each of us knows no one landing against the assigned pattern will escape a talk with a staff member. Exit separation is as important a safety issue and should be treated with the same respect. It needs to be a matter of policy for consistency. There is not an original idea on this subject here. This is the best knowledge which my mentors passed on to me. Here are a couple of related articles which go into greater depth about these concepts and solutions to these problems. I hope it is clear we must go about things in a more thoughtful and consistent way to avoid similar incidents in the future. http://www.dropzone.com/safety/Exit/Exit_Separation_Revisited_628.html http://indra.net/~bdaniels/ftw/sg_skr_dealing_1_uppers.html
  9. There are 'known' problems or 'no' problems? Please clarify your response. Thanks. JC
  10. If you are using a SR100, could you answer a few questions for me. Does it skip? How is the video quality? Are you pulling stills from the video? How is the quality on those? What other cameras have you flown with and how does the SR100 compare? What companies are manufacturing a mounting box for the SR100? Which box are you using? Thanks! JC