nigel99

Congrats

I've been accepted into a part time Masters degree at Curtin. The other good news is that there is funding in place for specific skills shortages within the defence industry. So 100% free for me, paid for by the government. Experienced jumper - someone who has made mistakes more often than I have and lived.

Congratulations. You are going to have fun when you get to do your hop and pop under AFF. All the other AFF students are going to freak about how low it is! Experienced jumper - someone who has made mistakes more often than I have and lived.

Earlier this week I saw an article that women are now cleverer than men. I found it interesting. The dynamics of employing women can be tricky in a small business environment. Especially if they are of child bearing age. As someone who ran a business, there is no way that we could have sustained maternity leave and a replacement with a total staff of 5 employees. Btw Australia is very woman friendly in the employment environment. I guess a huge skills shortage makes people flexible. Experienced jumper - someone who has made mistakes more often than I have and lived.

Damn Andy sad to hear the news - you'll have to come this side of the world. Hope you have a good time, I thought you were joking about finding a spot on a nude beach

I'm also pretty sure it was an experienced jumper and poster having some fun. Experienced jumper - someone who has made mistakes more often than I have and lived.

Thanks. On the bright side, at least I know I didn't pick up something nasty from surfing dodgy websites Experienced jumper - someone who has made mistakes more often than I have and lived.

Out of curiosity, did you specify AGL? That seems like a potential point of confusion, in the unfortunate event of a claim. No, but fortunately we are at sea level here. For the Australians it is TAL ( Australian super underwriters) they accepted death cover at ordinary rates, but income protection and permanent disability have skydiving excluded. That's not a problem for me, as work provides a scheme. Experienced jumper - someone who has made mistakes more often than I have and lived.

I've just adjusted my life insurance, and they have a revised disclosure statement. I disclosed skydiving and they asked for number of jumps per year. I got a follow up call and they wanted to know the equipment used, and the height. I answered with the brand and model of my container (tse teardrop) and altitude not higher than 14k. Anyone see a problem with that detail? Does it mean I might not be covered if I borrowed someone else's rig? I found it interesting how detailed and knowledgeable the skydiving questions were, compared to previous encounters. Experienced jumper - someone who has made mistakes more often than I have and lived.

I'm also getting the ads. Often makes it impossible to read the first 2 or 3 posts in a thread. Fingers crossed it gets sorted soon. Experienced jumper - someone who has made mistakes more often than I have and lived.

I'd love to look under the hood of a Cypres. Interesting about the plastic bag, pretty obvious that it could cause a problem (in hindsight of course). Experienced jumper - someone who has made mistakes more often than I have and lived.

Those MI-8's are the best! They carry as many or more than a twin otter, have a nice tailgate and, well, they're helos. Vskydiver and I jumped those down in Acapulco years ago. I'm jealous of anyone who jumps them all the time. Most helo specialty jumps are out of smaller helos. Cramped seating, new sets of snag hazards, and that tricky, slicky skid to climb out onto. I've even seen video of a woman jumper getting her chest strap caught on the skid. Such a jump calls for a little more ability and awareness than just flopping out of a Caravan door.

As a picky eater, I'd be happy to prove to you that you're wrong Best pick up line of the week, sir.

I really wish I would push boundaries more. I am way too conservative for my own liking, it's just hard to change the way you've behaved for nearly 40 years. The jest example of too far that I know of, a draftsman that I worked with. He was in his 60's and no woman at work was safe from his advances. I'll never forget September 11th. As the news broke around the office, he walked up to a couple of the female staff and said "shit we all could die, fuck me now and at least you'll die happy". How he never got into trouble I don't know, that kind of stuff went on all the time, it's just the most shocking incident. Experienced jumper - someone who has made mistakes more often than I have and lived.

As a picky eater, I'd be happy to prove to you that you're wrong Best pick up line of the week, sir.

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.