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AAD Statistics

 


dontlikemustard  (B License)

Jul 24, 2012, 10:50 AM
Post #1 of 11 (1755 views)
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AAD Statistics Can't Post

do we have statistic reports that show Cypres vs Vigil failure percentage rates?

Also, reading the Vigil reviews, what is your opinion on this statement:

" I personally like all the things I listed in the "Pros" section at the beginning of this review, but my favorite feature of the vigil is the way it determines if it should activate or not. Unlike the Cypres Expert, which decides at 1000ft to activate at 750ft if the parameters have been met (a person who deploys at a low altitude and snivels through 1000 ft at a speed greater than 78 mph will get a reserve opening at 750ft even if their main canopy is fully deployed at 900ft), the Vigil measures the speed of descent and calculates the estimated time to activation altitude every 8th of a second. The result (as I understand it) is that the situation that would result if a two-canopy-out situation in the example with the Cypres above, would not have the same potentially desaterous consequences with a Vigil. This wold have eliminated at least three two-canopy-out situations that I have witnessed over the years. This feature alone makes the Vigil a better choice in my opinion."


I found this online regarding the cypres,

http://www.skysurfer.com.au/...S_AAD_FACT_SHEET.pdf

but could not find something for the Vigil.


Skybear

Jul 24, 2012, 11:09 AM
Post #2 of 11 (1730 views)
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Re: [dontlikemustard] AAD Statistics [In reply to] Can't Post

In reply to:
Unlike the Cypres Expert, which decides at 1000ft to activate at 750ft if the parameters have been met (a person who deploys at a low altitude and snivels through 1000 ft at a speed greater than 78 mph will get a reserve opening at 750ft even if their main canopy is fully deployed at 900ft)

Simply not true. Cypres calculates in real time and thus decides at 750 feet to fire or not. Of course it also can decide lower, in case you reach more than 35m/sec again after being slower at 750feet. In doubt ask Airtec, that 's where I got this info from.

The fact sheet is very suspicious, as it does not state the name of the author or any sources. That doesn't make it seem much reliable.


sundevil777  (D License)

Jul 24, 2012, 11:29 AM
Post #3 of 11 (1707 views)
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Re: [dontlikemustard] AAD Statistics [In reply to] Can't Post

In reply to:
the Cypres Expert, which decides at 1000ft to activate at 750ft

That is a complete mischaracterization, or in other words, simply not true. I also think the Vigil "recalculation" frequency is a bit of marketing hype, and it is wrong to conclude that a Cypres "calculates" slowly in comparison.

Belly flying will result in a bit of a low pressure area where the sensor is on your back. That will be true for a Vigil also. To compensate for that, the actual firing altitude is adjusted. which makes it fire a bit higher if you're not belly flying at that time, and can also happen during canopy inflation (standing position).

Without the ability to determine a jumper's orientation, it makes sense to make the adjustment. You either allow the firing to happen lower for one scenario (already very low - I wouldn't want it lower), or allow it to happen higher for the rest. I think the Germans took a reasonable approach.


(This post was edited by sundevil777 on Jul 24, 2012, 12:23 PM)


piisfish

Jul 24, 2012, 12:54 PM
Post #4 of 11 (1639 views)
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Re: [dontlikemustard] AAD Statistics [In reply to] Can't Post

Bullshit review.


pchapman  (D 1014)

Jul 24, 2012, 1:53 PM
Post #5 of 11 (1605 views)
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Re: [dontlikemustard] AAD Statistics [In reply to] Can't Post

In reply to:
I found this online regarding the cypres,
http://www.skysurfer.com.au/...S_AAD_FACT_SHEET.pdf
but could not find something for the Vigil.

... Probably because nobody has created an equivalent paper attacking the Vigil that vehemently. That "fact sheet" has been out for a while and has an unknown author as far as I know.

Both the Vigil and Cypres make a correction for the burble behind a skydiver who is belly to earth -- which means both will fire a little higher (c. 250' more) for someone who is vertical after a low main pull.

Airtec firmly rejects the notion that any of the fatalities listed were somehow the fault of the Cypres. Yet they have never deigned to address the accusations on a case by case basis -- which doesn't necessarily help their case. But finding any evidence, either way, is pretty hard. The amount of information available to the public on some of the accidents is pretty slim.

Some of the accusations in the CYPRES FACT SHEET are laughable, while some cases are ones where skydivers just don't know the explanation -- and do indeed wonder what the heck happened.


-- Example of a laughable accusation:
3/5/2005 (actually 5/3/2005 in the US notation used in the document) Perris Valley

The paper includes this case in their list of "failures". The paper says "activation too low", with "claimed cause" (that is, what Airtec says) being "wrong altitude correction".
That was the Susan Spray fatality, where as far as we skydivers know, it was made very very clear that she turned on the AAD at her home near sea level before driving on up to Perris at a higher elevation.
So it was clearly not a Cypres failure in any way, unless you truly believe there's a big Airtec conspiracy that has everyone fooled.

-- Example of an accusation that seems very weak, and deceptive because of what was omitted:
23/2/2005 Skydive Arizona

The paper just says that the Cypres "did not activate". But looking up the accident on dz.com, it looks like the jumper pulled the cutaway handle only part way, only releasing one set of risers, spinning the rest of the way down, only manually pulling the reserve just before impact. That doesn't prove either way whether the Cypres was somehow not working right, but spinning under a partial canopy is a very good reason why the Cypres might never have reached firing parameters.

-- Example of an accusation which is or is not valid depending on whether you trust Airtec at all:
6/15/2002 Sky Knights (WI)

Junior jumper didn't deploy anything. The dz.com thread has one report that the Cypres was off. The AAD was supposedly sent to the manufacturer but no report is known to the public. Some of us might trust that the AAD had indeed been off all the time. The paper lists it as a "failure" though. Even if you don't buy that, they do list quite a large number of cases where the Cypres was supposedly not turned on. That is something not totally unreasonable to question -- were there really that many people who happened to have left their Cypres off? (The paper lists 17.)


-- Example of an accusation where skydivers just don't know:
28/12/2008 Perris Valley

That's the Brooke Baum case. No main activation, and a reserve seen only to start coming out at only 150' or so. The paper says the problem was that the Cypres fired too low, and indeed quotes part of the civil suit brought by a member of Brooke's family as evidence (as if getting sued in the USA actually is evidence of committing a wrong!).

That is one of those cases where a Cypres fired yet the reserve never got out in time. There's a lot of speculation in our industry about issues with cut loops being slow to push out of grommets, and overly tightly pocketing containers. A PC can also get stuck in the burble for a moment if the jumper is really stable, or in other cases, if the jumper is tumbling, they might snag the PC for a moment, or have it pull at an angle that makes it difficult to remove from a modern container. (e.g. a recent video of someone with a reserve hesitation because he was on his back with the bridle coming over his shoulder -- he manually grabbed the reserve bridle and pulled the bag out of the container.)

It is those types of accidents, where the Cypres fired but the reserve didn't come out in time, where there's a lot of reasonable speculation. Someone could suspect the Cypres for being unreliable in gauging altitude, or suspect non-AAD causes, depending on the person's personal beliefs about AAD reliability.


I personally find the paper ridiculous and highly biased, but at the same time a few of the questions it asks are valid to ask, because we don't actually have much proof of what really happened in some accidents.


Premier LouDiamond  (D 25931)
Moderator
Jul 24, 2012, 4:03 PM
Post #6 of 11 (1558 views)
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Re: [pchapman] AAD Statistics [In reply to] Can't Post

Quote:
Probably because nobody has created an equivalent paper attacking the Vigil that vehemently. That "fact sheet" has been out for a while and has an unknown author as far as I know.


The Cypres and Vigil "fact sheets" were created by the same person who happens to work for another AAD company, it's not hard to trace either back to the author if one knows how. Both were created to paint a negative picture as some of you have deduced, they shouldn't be taken seriously as they are highly questionable.


I would also recommend that a few of you take the time to go back and review your information or better yet, call /e-mail Cypres and ask about what happens at what altitude and the parameters required to reach the firing altitude of the unit as it appears, based on your statements, you don't fully understand them.


sundevil777  (D License)

Jul 24, 2012, 6:19 PM
Post #7 of 11 (1518 views)
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Re: [LouDiamond] AAD Statistics [In reply to] Can't Post

In reply to:
I would also recommend that a few of you take the time to go back and review your information or better yet, call /e-mail Cypres and ask about what happens at what altitude and the parameters required to reach the firing altitude of the unit as it appears, based on your statements, you don't fully understand them.

If someone in this thread got something wrong, then why not correct it? I don't see the purpose of being so vague.


Premier LouDiamond  (D 25931)
Moderator
Jul 24, 2012, 11:30 PM
Post #8 of 11 (1463 views)
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Re: [sundevil777] AAD Statistics [In reply to] Can't Post

Quote:
I don't see the purpose of being so vague.

I thought I was rather clear in that they should speak to the manufacturer. Why do I suggest this instead of providing the answers? A few reasons actually. First off, a search would reveal that there are several very in depth explanations on the functioning parameters that need to be met. Second, I know that by typing a detailed response out it will only generate pages of responses that argue the facts or simply obscure the answer with white noise. Third, if the small group of people that really want to know about something be it this topic of any of the others in any forum, will do a search and or will call/e-mail the manufacturer for a detailed explanation. Lastly, what better place to get it straight from the horses mouth than the manufacturer? It also goes back to that old analogy, "give a man a fish, he eats for a day, teach a man to fish, he eats forever".

So many times over the years I have seen the same questions in the forums, which is natural given the turn over in the sport, however it always tends to be the same small group of people providing the correct answers. I think this is a reflection of todays society of instant gratification and wanting something for nothing or very little effort. If more people took the time to do some researching on their own and find the answers instead of relying on others to always provide them to them, perhaps they would remember these answers and one day be able to repeat them to others. No one thinks to RTFM or call/e-mail the manufacturer, instead their first instinct is to go online to a forum some where and ask questions and take strangers answers as gospel over what can be found in the manual or be had by contacting the people who make the item in the first place. Because of this laziness I think there is actually more misinformation and or partial facts out there than facts and people are happy to perpetuate them rather than do a bit of the work themselves. Everyone wants an AAD that is infallible but no one wants to take the time to understand how and why it works other than pushing a button when they see a light flash in front of them. And that is why people will believe the shit found in those "fact sheets" or what they read on the internet. Hence, my suggestion to contact the manufacturer in hopes that at least one person would and they would get the indisputable truth to this question and many others.


nigel99  (D 1)

Jul 27, 2012, 12:53 AM
Post #9 of 11 (1307 views)
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Re: [LouDiamond] AAD Statistics [In reply to] Can't Post

FWIW I emailed Vigil with a question on my AAD and never got a response. Admittedly I have never followed it up and it is slightly plausible that my email (from a gmail account) got caught in a spam filter.

But I agree the manufacturers would be the best source of information, just bearing in mind they are there to sell product so views will naturally be biased.


obelixtim  (D 84)

Jul 27, 2012, 3:02 AM
Post #10 of 11 (1281 views)
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Re: [pchapman] AAD Statistics [In reply to] Can't Post

In reply to:
Airtec firmly rejects the notion that any of the fatalities listed were somehow the fault of the Cypres.

And fair enough too.

NO fatality is the fault of an AAD. They are ALL the fault of the jumper.

Its a backup device only. Why do people forget that?.

Failure to take responsibility for their own actions, I guess.


erdnarob  (D 364)

Jul 30, 2012, 2:25 PM
Post #11 of 11 (1125 views)
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Re: [dontlikemustard] AAD Statistics [In reply to] Can't Post

ANOTHER COMPARISON BETWEEN VIGIL AND CYPRES :

Both Vigil and Cypres will switch off automatically after 14 hours. For the Vigil if within those 14 hours you leave the DZ with the AAD and go at a place located at + or - 150 ft above or below the DZ or more, the Vigil will stay on. This is not the case for the Cypres.
Suppose now that you switch on your Vigil at 8:00 AM and you take off for a night jump at 9:50 PM, even if normaly the Vigil is set to switch off after 14 hours, in this case at 10:00 PM if on the ground, being airborne it will stay on and you will be protected even past 10:00 PM. Not the case if you have a Cypres, therefore you will have no protection. A guy at Farnham Quebec with who I had this discussion, told me that story happened to him. He was equiped with a Cypres and found out that he has not been protected for a night jump because he had exceeded 14 hours during the airplane ascent.

Conclusion : whatever is your AAD, if you do a night jump, switch it off and switch it on again before the night jump. If you are not going to do a night jump, switch your AAD off after your jumping is over for the day. Also, before every jump, check your AAD status on the console window.Wink



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