nigel99

As a picky eater, I'd be happy to prove to you that you're wrong Experienced jumper - someone who has made mistakes more often than I have and lived.

Have you heard the saying 'slap her on the thigh and ride the wave in'? Fat people need loving too. I shouldn't be joking about this stuff, I just spent 2 days doing sexual harrasment and discrimination training. Experienced jumper - someone who has made mistakes more often than I have and lived.

I want to barf. Woman sitting across from me in the train probably weighs 250lbs. She's in a tiny mini skirt and chewing gum loudly. No problem though, I'm an engineer so I'll just buy her roses and ask her out to dinner :) Experienced jumper - someone who has made mistakes more often than I have and lived.

it is a vintage piston plane. What do you expect ? a rocket rate of climb ? Plus sometimes you MUST level or descend, due to ATC/other aircraft/changing weather etc... I have my choice of AAD, and it is of "that other brand" Just stating my view that a vigil is more likely to 'misfire' in a slow climbing aircraft. Just remember that the very strength of a cypres means that in a reasonable number of scenarios, you may as well not have it, as the safety will kick in and it will not fire. Look carefully at the diagrams showing the restricted zones when jumping into different elevation dzs, and then remember the whole climb, descend and hold limitations. Not at all saying this is wrong of the device, just jumpers often don't know enough about it. For what it is worth, I'd choose Cypres if selecting an aad new off the shelf. Experienced jumper - someone who has made mistakes more often than I have and lived.

Neither of the user manuals go into any detail on 'how' the devices work. I didn't see anything in the Cypres user manual on accelerometers, and in the vigil manual I saw nothing about how it initially uses 3 readings to estimate the descent rate, and then successively refines the data to improve the accuracy/reliability of the result. The Vigil patent has a fairly detailed flow chart on how they might be doing things. Similarly there is a block diagram showing how a Cypres might be utilising hardware elements. While the method that is described by Vigil gets more reliable with time, there is a window where it is initially quite vulnerable. IF a Vigil is working as described in that document, with no additional checks and balances, it would be wise to avoid situations where the aircraft is climbing slowly or holding below the activation altitude (2000ft for tandems). At least if the plane is ascending rapidly, any temporary blips in pressure should result in a reduced ascent rate, rather than being interpreted as a descent. As soon as you have a descent reading below activation altitude, you're completely dependent on the rate calculation. Experienced jumper - someone who has made mistakes more often than I have and lived.

One thing I've learned is that patent law is very, very weird and what might squeeze past one examiner, might not squeeze past the next. But from USSC Gottschalk v. Benson (1972), European Patent Convention Art. 52(2) and others, in general terms you cannot patent an algorithm. If you have (and it is entirely possible you squeezed one past your examiner somehow), then you either have a challengable patent or your algorithm is tied to some implementation thereof. I would also be interested to know how you managed to get a world wide patent since they don't exist. To get one you'd have to patent your design in 190+ different countries which again is possible if you were prepared to fund your patent attorneys new yacht on the back of it. Ok I simplified by saying world wide. It was filed in the US with lots of money (spent by the client) on getting coverage in most other major jurisdictions (Europe, Japan etc) . The primary filing was done in the US. The 2 UK patents that I have are ONLY filed and provide coverage in the UK, as my pockets weren't deep enough to do anything else. I realise that algorithm means something different to different people. So ok what I called an algorithm is a method for determining the best routing/switching of radio packets (one of my patents). Anyway - have a look at the Vigil patent - I would define that as a patent on their algorithm. I'm happy to take the patent specifics to PM, if you want to clarify stuff. I don't really want to sidetrack the main point of my thread, being the implementation/trade-offs that the manufacturers have to make. By the way. 2 weeks ago I flew from one dz that was 1200foot higher than our destination. There were 3 of us on the flight, 2 Cypres and my Vigil. We did not climb above 1000ft from our take off point. In this scenario, neither Cypres would have fired if required to do so. My Vigil would have been the only 'operable' AAD (although it was off). We didn't exit the plane, but just giving an example from personal experience. Experienced jumper - someone who has made mistakes more often than I have and lived.

That's because you can't patent an algorithm, only the hardware designed to process the algorithm. Have you got the patent numbers? Jack, I'm far from an expert on this but in practical terms you are wrong. I've personally got my name on a world wide patent filed in the US that is for an algorithm, I've also got a patent filed in the UK for an algorithm. It might be a definition thing, to me an algorithm is a method of doing something, so a software decision tree/program flow would be an algorithm. To a mathematics person it is probably different. I know you can't patent abstract ideas. The patent number for vigil is EP1084950 just search on espacenet for it. The cypres patents are in Helmut Cloth name and I just used the name search for theirs. Cypres patents haven't always been translated from German. Experienced jumper - someone who has made mistakes more often than I have and lived.

You can buy accelerometers with freefall detection (like the ones that go into hard drives) and I think this would be a key piece of data when deciding when to fire the AAD. Just that a quick read shows that doing so without a license from Cypres, would probably infringe their patent with the way the claims are worded. By the way a friend reminded me today of an incident in the early 90's at our club, a visiting jumpers Cypres fired as he dropped his rig on the floor after a jump. Experienced jumper - someone who has made mistakes more often than I have and lived.

I'm always weary of trying to 'improve' on designs without knowing the intimate details. On a safety critical design and pseudo military stuff an failure modes and effects analysis will have been done. In principle it sounds easy, just don't fire when you've not gone above 1500 feet. What we forget is the algorithm is intertwined with the height calculation. From what I've read the vigil doesn't 'arm' at any altitude as such. It simply looks for a minimum of 3 simply looks for 3 successive readings showing a descent rate that exceeds the threshold for speed, whilst below the firing altitude. The readings are taken at 1/8 second intervals. That is why I believe the plane was climbing relatively slowly when the event took place. Just a combination of factors. My guess is if we collated all the incidents they would involve student mode (predominantly), slower climbing aircraft such as a heavily laden 182 on a hot day etc. There is stuff in the vigil user manual regarding beeps and lights at activation altitude, I'm trying to figure out if my curiosity is worth potentially causing a cutter to fire. I've got a vacuum chamber at work and would like to see the lights and hear the beeps, I can't do that in an aircraft as my aad is against my back. I'm just worried that I dump the air back into the vacuum chamber too quickly and cost myself a new cutter. Experienced jumper - someone who has made mistakes more often than I have and lived.

The big plus on an accelerometer is that it gives you an independent variable to compare against. This means a pressure change with no corresponding change in acceleration is a false positive and can be discounted. I think Adam has done a very good job of explaining other stuff. Just both aad manufacturers claim.much better resolution than the 260ft he mentions. Experienced jumper - someone who has made mistakes more often than I have and lived.

Um, don't think that's what they meant, by "low drag"... Oh and some us still have those big ass rigs and canopies, hell I just up-sized my reserve last yr. Low drag is due to the small size of the pilot chute, due to it having to fit into the rig? Is that right? Experienced jumper - someone who has made mistakes more often than I have and lived.

The recent incident posted by Peek prompted me to do some research on the patents published on Cypres and Vigil. The good thing about patents is it generally shows you how the various companies do things. Firstly it looks like Cypres have covered the market in using a combination of temperature and pressure sensors along with an accelerometer. This patent runs until 2018 and is pretty broad in scope and probably prevents the competition from accessing those without using some clever workarounds (you can almost always work around), alternatively the competition could license the technology from Cypres. Details of the Cypres algorithm aren't patented as far as I can tell - they have chosen to patent the hardware implementation. This means that the details of their algorithm remain 'secret'. Vigil uses a successive approximation algorithm. At first glance the calculation gets more reliable the LONGER you are in free-fall. The parameters used to estimate the descent rate are least reliable as you climb through the first few hundreds of feet due to how it appears to work. Feel free to read the patent and flow charts and agree/disagree with my assessment. I'm pretty sure reading it that the student mode is most susceptible to false fires and the aircraft simply 'dropping' through turbulence over a 3/8's of a second period could cause a fire. In short I believe the Vigil is designed to be very accurate in descent, AFTER you have climbed to a reasonable altitude. I think a Vigil may not be very accurate following a short free-fall descent. So on a low altitude hop and pop things could be interesting. Note that as the Cypres algorithm is not published similar concerns may apply - however they have an accelerometer that gives an 'independent' metric for the algorithms, providing substantially more data for decision making. Having read the patents, I would strongly recommend a Cypres over a Vigil, and am considering trading my Vigil in for a Cypres. I'd be really interested in seeing other peoples analysis of the various patents. This is obviously my interpretation of public documents, and companies don't always do things in the way the patent is published (and they're under no obligation to do so). So for example cypres may not use an accelerometer. Experienced jumper - someone who has made mistakes more often than I have and lived.

Thanks, I've already been chatting with Kurt and he has been very helpful. I'm quite happy being the local organiser, I just need to get to know more locals (which takes time, especially when you can't get out the dz often). Experienced jumper - someone who has made mistakes more often than I have and lived.

I've actually surprised there hasn't been more people reconstructing the OP to fit 'Picky Daters' Luckily I don't fit his profile, so the thought never crossed my mind. Someday he'll come out of the closet though and then well be hearing about how bitchy men are Experienced jumper - someone who has made mistakes more often than I have and lived.

My parents forced us to eat all sorts of shit, and I'm a fussy eater. To be honest I'd rather be a fussy eater than some of the other social fuckups that people have. If you tell me I've just eaten fish and there is reasonable doubt, I guarantee you'll be cleaning up puke. I have no control over it and it's not high on the priority list. Especially that most people who try and convince me to eat fish, tell me it tastes like chicken - I'll stick to chicken. As to more annoying than picky eaters, people who constantly bash women and specific professions (engineers, lawyers, teachers etc) are way up my list. Experienced jumper - someone who has made mistakes more often than I have and lived.

I hope you're right Andy. You're probably the only instructor left on dz.com prepared to treat Shah seriously, I hope he takes the opportunity to learn from you Experienced jumper - someone who has made mistakes more often than I have and lived.

There is no reason to practice or perform rear riser landings. Broke a steering line on opening, landed on rears rather than cut away. Chris, someone up thread mentioned an undercurrent jumper with low jump numbers may be better off cutting away. Obviously gear maintenance counts, because you don't want the toggle to fall off at 300 foot. I am curious about it, as I'd rather not land on rears. Hopefully I'll get some good education in 2 weeks time when I get crw coaching

I've no idea why they have those requirements. The last time I had the opportunity I fell below the minimum experience. My guess is that it has to do with lower exit altitudes with less airspeed. A less experienced person may freak out. But it doesn't hurt to ask,. Experienced jumper - someone who has made mistakes more often than I have and lived.

Damn those magic rotors that are blowing air down, but suck parachutes up Experienced jumper - someone who has made mistakes more often than I have and lived.

And people think you are being funny, a skydiver afraid of heights! Someone once told me that he are afraid, because our subconscious is wanting us to jump, or at least calculating a jump. He reckoned that's why we're not afraid when jumping. I've always liked that explanation, even if it is a load of rubbish. Experienced jumper - someone who has made mistakes more often than I have and lived.

I've seen both B and C required, depending on the organiser. I've not come across low jump number A license holders being allowed (I know someone with 800 jumps and an A license, and am pretty sure he's jumped helicopters) Experienced jumper - someone who has made mistakes more often than I have and lived.

How the heck is tunnel going to help his canopy control? To the op the most scared I have ever been was looking for my wife following her level 1. The compassionate Dzo who was in the car complaining about not needing another fatality, really didn't set my mind at ease Experienced jumper - someone who has made mistakes more often than I have and lived.

Squeak, having had a chance to digest what has been said, it looks like the driver for this is airport access. I honestly don't know enough about which dz's will be negatively affected. As far as I can tell the US dropzone closest to my heart will benefit as the skyride one nearby operates into a tiny landing area at the airport (not entirely sure if it is federally funded though). As a USPA member I'm prepared to do my bit to help fellow skydivers. I think the USPA members are going to have to 'grow up' though and lose some of the attitude that all rules are bad. Experienced jumper - someone who has made mistakes more often than I have and lived.

Those "27 supposedly reported issues" have been written up by the FAA and the NTSB. Those 27 issues are now part of the FFA Accident and Incident Database (AIDS) with a 15 digit reports number. The FAA is using these reports to support implementation of AC, AC 150/5300-13. Remi, do you think they are going to all this trouble to make it easier for jumpers to gain assess to airport? I don’t think so. Sparky Due to the rather tenuous nature of the incidents, could the FAA not be showing how infrequent problems are? Sometimes a case study with few incidents over a 30 year time frame is a powerful positive argument. Experienced jumper - someone who has made mistakes more often than I have and lived.

It's an interesting topic. I've got zero knowledge of tandem so can't comment either way with any authority. Personal opinion is that it opens the door to problems. Putting a camera on a tandem passenger, gives them the motivation to capture a shot of the plane they are about to go in, increasing the potential for a prop strike to occur. It increases the snag potential simply by being there. Commercially it seems to undercut the dzs own income stream. It seems hard to justify charging much, when the client is doing the work. Pretty sure most people who shoot their own video don't care about paying to have it edited. From a business point of view seems it would be better to offer a quality product. Experienced jumper - someone who has made mistakes more often than I have and lived.