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apoil 0
QuoteNot really, you know what date the batteries went in there from the reserve card, just look at the owners log book from that date to see how many jumps they've made. But who is going to check all this?
I said it can't be proven.
The log book could be incorrect.
Someone else could have jumped the rig.
The logged jumps could be on a different rig.
apoil 0
Quotewell you are only hurting yourself for not replacing them after 500 jumps. I know a JM who had over 500 (don't know the exact number) on his set of batteries, chased a student low, pulled for her then pulled for himself, I was at 1500ft and saw him fall way past me before deploying his main. (he said he was in the saddle at 600 feet) He cypres did not fire. This was not a malfunction of the cypres, his batteries were really that low.
I had a battery said go dead on me before the two years were up. there were well over 500 jumps on it. I'm over 500 jumps on my current battery, therefore I check the voltage every time I turn it on. If it powers up with 6.4 or 6.3 volts it will most likely work even with 500+ jumps on it.
As an aside, that JM violated procedure by not having an open container by 2000 ft as stated in the BSRs. Chasing a student that low actually puts them in greater danger. They have a better chance of survival with the AAD they are required to wear and the instructor in their airspace at that time is a serious hazard. At 2000 feet, saving yourself is a priority. If you are EVER conscious and need your cypres, you should be thankful you are alive and re-evaluate your participation in the sport.
jerm 0
QuoteNot really, you know what date the batteries went in there from the reserve card, just look at the owners log book from that date to see how many jumps they've made. But who is going to check all this?
you're assumung everyone diligently logs their jumps.... and further assuming that they would fess up to logging their jumps if the numbers were ever questioned and NOT in the jumpers favor, "oh, i don't log my jumps, i dunno how many i've put on the cypres *tucks logbook under the carpet*"
also have to wonder why it would ever be an investigated issue if the person was still breathing on their own.
Landing without injury is not necessarily evidence that you didn't fuck up... it just means you got away with it this time
billvon 2,991
>It would appear so, as I mentioned in earlier posts, the 2 year limit is gone.
I doubt it very much. Primary lithiums (i.e. lithium thionyl chloride) batteries are about the best long-term, low power source out there. A system that uses 1/2 the power would be good for 4 years, which would mean the batteries will make it to the next inspection cycle. 4 years isn't that long for a lithium primary.
sundevil777 102
I don't care how efficient the new electronics are, if I someone uses their rig for one jump a year, I contend it is using a whole lot less energy than putting 500 jumps or more a year on the new units.
So, it seems that either the 2 year guideline is unnecessary, or there is a difference in the batteries.
billvon 2,991
>years REGARDLESS OF USAGE?
Because 'off' may not be the same as zero current draw. Alternatively, because it was tested that way, and they have no reason to retest the batteries for a four-year life. If people refused to buy it due to the short battery cycle life, they might have an impetus to retest - but right now they're just about the only game in town.
>If there is some good reason for it, then why don't the new batteries
>have this requirement?
The new design may have a lower off-state current draw, or may have a big enough capacitor in the firing circuit so that even a nearly dead battery can fire the cutter.
>I don't care how efficient the new electronics are, if I someone uses their
> rig for one jump a year, I contend it is using a whole lot less energy
>than putting 500 jumps or more a year on the new units.
Only true if the off-state current draw is zero. In practice batteries can last a very long time (over four years) under good conditions - but you won't get a rigger to repack a reserve with old batteries. If this bugs you get your rigger's rating and keep the batteries as long as you like.
USPA 0
QuoteSo, it seems that either the 2 year guideline is unnecessary
The 2 year guideline is necessary, we had a fatality at our DZ back in '95 when in The Netherlands the 2 year rule, was advisory, not mandatory. The jumper in question died because she didn't pulled any handles. The cypres was barely used and therefore it wasn't deemed necessary to replace the batteries at 2 years. The cypres was turned on correctly without errors, but did not fire, due to low batteries.
A remark I have to make thought, I started jumping in '97 and became part of the staff in '98, so I wasn't there when the incident happend.
ZigZag 0
A manufacturer with the status and experience as Airtec, would do well to improve their product. They now have amassed over 12 years of data, and the 4-year & 8-year maintenance schedules on well over 30,000 units combined, give this company a wealth of information, that should allow them to publish improved performance criteria for the new models of the Cypres. I find it difficult to second guess a manufacturer of this calibre. Neither does it serve any purpose to associate old or new battery performance in light of the new model Cypres and the improved technology. 12 years is an extremely long time for a single generational improvement in an electronic device. Consider all the software improvements over the last 12 years, or let alone processor speed improvements in computers. Airtec could only be commended for its conservative approach in interpreting the data it has collected. Once again, even the new improved version of Cypres is only a back-up device. It will fail at the most inopportune moment, when some"body" relies on it to work, but wants to relieve personal responsibility for ones actions. You just might forget to switch it on.
At this point it is good to see the "Made in Germany" label again, with some true grit.
sundevil777 102
QuoteBecause 'off' may not be the same as zero current draw.
So you think it possible the new units use less power when on and being used (jumping) than the old version when it is off?
I would still expect the 'off' current draw to still use less battery power than the new version 'on' and being used a lot every day.
QuoteAlternatively, because it was tested that way, and they have no reason to retest the batteries for a four-year life.
Wasn't the two year life rule started well after the introduction of the Cypres?
I think it is remarkable that Airtec is so confident in the life of the batteries that it is not even possible to change the batteries 'in the field'. This makes me wonder how they accomplished this. I still think there is more to it than more efficient electronics.
No big deal, just interested in how our gadgets work.
sundevil777 102
The rambling question I asked:
How can you be so sure that the CYPRES 2 battery will last 4 years? What is so different that allowed you to get rid of the 2-year battery change requirement? I don't see how this could be from more efficient electronics alone. Is the battery a new technology type? If not, why no 2 year limit?
The slightly evasive but still informative answer:
- one of the many items in the list of requirements for CYPRES 2 was "no battery hassle at all for the owner", it took a long time and a lot of effort to find the solution - you are correct in thinking that it is not only the electronics - without being rude, we have to say that the information is proprietary, and that we just can not explain all technical details about CYPRES, as there are those out there that have an interest that is more than just to satisfy their curiosity, sorry
Two times have I checked a jumpers protrack after a cypresfire. Ending with two canopys. Both showed deployment altitude 800ft. One of them resulted in a downplane.
I have also checked two protracks after lowpull, that showed 900ft. Cypress did not fire...
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