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Is that index linked? $8 10 years ago would be, I don't know, $10 on average index linked?

Don't even try. You are wasting your time. Unskilled and Unaware of It: How Difficulties in Recognizing One's Own Incompetence Lead to Inflated Self-Assessments http://www.apa.org/journals/features/psp7761121.pdf

Any chance you could post the algorithm?

Thanks for the considered reply. My thoughts are that, no matter where the air leaks out, the pressure is the same. The rate of 'refill' is not really important, because the 'ram air' effect keeps the pressure fairly constant. So, in princple, you have constant air pressure in the cells, regardless of where the air escapes from the cells. Now, I'm no expert by any means. Parachutes have a touch of voodoo about them at the best of times (in my opinion

The internal pressure in the cells should, in principle, act equally on the internal surfaces, top and bottom. If there was a significant difference in the pressure on the top and bottom surfaces, then the cells would collapse. Consider, for example, a sealed balloon. The internal gas pressure acts equally around the internal surface.

I would think a flat position gives the best separation between the reserve pilotchute and trailing materials. When you move from a flat position, towards a head low position (or head high position), the separation between reserve pilotchute and trailing material reduces, with the separation reducing to zero for a fully 'head down' (or 'head up') position. Me? I'll be as flat as a ten-day old beer should this unhappy situation befall me... YMMV

Believe me, I get it. To all, thanks for the helpful posts.

Here is the data: The wind at exit altitude (12k) was 10 knots. The separation between exits was 5 seconds. When I exited, I had sight of the previous jumper. I believed the horizontal separation was sufficient. I maintained visual contact for 4/5 seconds before lining myself up for the short track.

Yes, you are absolutely right. That is another one of the factors that culminated in a 'near miss'. I am satisfied that I tracked at about 90 degrees to the jump run. I was quite particular in that regard. For a 15 second squirt, a few degrees should not matter too much (in my newbie opinion). But, the point is that better communication of intention would have negated the problem. I fully accept my own failings, and I post only in an effort to raise awareness, and mostly for new jumpers.

It was a track off the flight line. We both tracked off the flight line. This was the whole point of the track - to get off the flight line.

I zoomed past an opening canopy in freefall today, about 20 metres to my right. I could see the whites of the other persons eyes. The scenario: I was doing a flat solo, exiting after another flat solo. The first jumper was deploying at 4500 feet, I was deploying at 3500 feet. I raised the exit order as a concern with the jump master, but the received view was that this would not be a problem. All of the skydivers exiting after me were AFF stiudents and instructors. I, because of the difference in opening altitudes between the other jumper and I, elected to do a 15 second track off the jump run, and away from the first jumper. Thinking myself to be in clear air space, I was not paying much attention to what was below. Unbeknownst to me, the first jumper had also decided, late in the jump, to track, and to deploy at 4000 feet rather than 4500. Both 'tracks' placed the jumper almost directly below me. I was in the process of reaching for my pilot chute when I saw the other jumpers canopy 'appear'. This episode was discussed with the CCI. Lessons: 1/ I should have seen the lower jumper. 2/ Do not track unless previously discussed with other jumpers. This applies to all parties. 3/ When solos are intended, put the highest opening solo out last. I feel pretty lucky to have got away without both of us getting killed. I would appreciate any comments on other lessons that can be learned.

I'm not sure what the legal liability is for the jumpmaster (in the UK) redarding the flight line check. I'm not a legal professional, but I think that simply ensuring that everybody has been checked by a skydiver qualified to do so (B licence) would not equal significant liability. Ultimately, assuming that checks have been done properly, there would never be an issue in this regard....

That is correct. All jumpers get a flight line check by another jumper, who signs it off on the manifest. Takes a minute. The jumpmaster for the load signs off on the manifest that everybody has been checked. It is no burden.

pilotdave makes an excellent point. I misrouted a chest strap earlier this year. I would have caught it during my own gear check, and I also expect the flight line check would have picked it up. Nevertheless, a frightening experience. I traced the cause of the misrouting to being preoccupied with my hook knife. It had a large loop, suitable for mounting on a leg strap, and it was always falling off my chest strap. I decided to be specifically focused on the strap in future. Yet, a few jumps later, I caught myself making the same error again. I ditched the hook knife, and got one that fitted the chest strap properly. Problem solved. I am now super fastidious about gear checks, particularly my chest strap. So, I think pilotdave's suggestion is very pertinent, and should be applied to all errors.

I think that is a really interesting point. A counter-view might be that if you only do 'straightforward' dives, your 'proficiency' might not require the same level of 'currency' required to be proficient for Instruction work or group freefly jumps, for example. I was really mainly interested in what skydivers from different countries regard as sufficient jumps to be current per annum. In the UK, I would be lucky to get 100 odd jumps in per annum, given the weather and the fact that three/four jumps per good jumpable day is enough for me.

Thank you. I was thinking more in terms of what skydivers think is 'current', rather than what membership bodies stipulate as minimum currency requirements.

I am curious about what comprises 'currency' (in jumps per annum) in different countries. I am often surprised at the numbers American posters put forward as minimum jumps per annum to be 'current'. I am, therefore, interested to hear what posters in other countries, as well as USA posters, regard as minimum jumps per annum to be 'current'. I appreciate that 'currency' might be considered to depend on discipline. Can responders please state country and, if relevant, discipline? Thanks!

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I am watching Born Survivor, starring Bear Grylls, ex SAS. He landed his parachute in the sea, talking at length about how how important it was to cut away at the right height just before entry. Then, he cuts away, and his RSL deploys his reserve, which reaches line stretch before he enters the sea. Surely this is not the right way to do a water landing? Surely he should have disconnected the RSL first? (Special Forces? Special needs...)

Diverdriver and Pilotdave. I actually just think of them as one person now. It's less confusing...

I jump a Dolphin AFF rig with the secondary release on the BOC pouch. I pack the pilotchute using Brian Germains technique, specifically because it appears to minimise the chances of a pilotchute getting bunched up and jammed if the bridle tries to extract it. That said, my 'plan' should I sustain a jammed pilotchute during a horseshoe malfunction is to open the BOC by pulling the 'reserve side' handle. This handle disconnects the pouch. Clearly, this is an altitude-dependent extra step. However, as I understand it, most horseshoe malfunctions seem to occur at altitudes higher than normal deployment altitudes, so it appears like a reasonable extra step on the rig I mainly jump.

This bit is the reason why I don't see a disadvantage for curved pins, perhaps not on reserves (if it ain't broke etc..), but why not on pull-out deployment systems? Would the curved pin not offer better protection from unseating, without adding another problem? For any given closing closing loop tension, I would not expect the pull force to change significantly when using a curved pin versus a straight pin. Not trying to reinvent the wheel.... Thanks!

Well, with respect, I don't agree. The withdrawal force is mostly governed by the friction between the closing loop and the pin. This is largely independant of pin shape. The bent pin argument is also weak. Every curved pin is 'bent'. They are not dangerous, and work routinely. They are 'bent' (curved) in a plane parallel to the grommet surface. Bent straight pins are a different problem, because when they are bent, they can have tight bends. In my view, a straight pin is far more likely to become 'bent', in the way that is dangerous, than a curved pin. Hence the question. Thanks.

(Maybe better for gear and rigging, but it is a safety question) Simple question, probably with a simple answer. My understanding of the introduction of the curved pin is that it was introduced to 'throw away' deployment systems to prevent the pin 'locking' when the pilotchute pulled it at a 90 degrees to its stowed orientation, as could happen with a straight pin. The curved pin can rotate and slide through the closing loop. A further advantage of the curved pin is that it can't be pushed out by pushing the tip of the pin. I've tried it, and the pin just rotates around the closing loop. Reserve pins and pull out pins are straight. Would these pins not be more secure if they were curved? They would be better able to withstand an 'unseating' if pushed, and the curved pin would not, as I understand it, affect pull force. Thanks!

Because it is third party insurance...