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davelepka

Offsetting ADD opening Altitudes WAS: Fatality - Cross Keys - 3/25/11

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Ignore Dave's personal assaults. He's very knowledgable but his approach is often lacking.

There's nothing wrong with you asking questions and challenging others ideas. If everyone simply accepted what Dave or anyone else said, they wouldn't be thinking critically. And that is stagnant and dangerous to the sport and the individual.

However, being so green you must, in the end, follow your instructor's advice and direction.
Life expands or contracts in proportion to one's courage. ~Anais Nin

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There's nothing wrong with challenging the status quo if you're willing to accept that you're wrong and that there's a good reason for the status quo. Things change all the time, new technology comes along (like AADs or skyhook) that affect what people do but that doesn't mean that we change without seriously thinking through the affects.

Dave's delivery isn't great but dismiss his opinion out of hand at your own peril.

I look forward to seeing the result of the inquiry on the AAD.

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Agreed. I'm not dismissing anyone's opinion, just the delivery style. As I said before, Dave and others are very knowledgable(moreso than myself), but asking questions even to the frustration of others is in no way out of line.
These forums are for shared learning and debate. It's through these types of discussions, whether here or in an R&D department, that advances in both product and procedure are made.
That's my only point.
Life expands or contracts in proportion to one's courage. ~Anais Nin

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Peter,
Talk to me when you get here.
Evidently, you didn't get the answers you wanted in the General forum (Raising minimum deployment altitude thread, post#99 and prior) about the AAD firing altitude question so you brought it over here.

This discussion should have stayed in the General forum.
My reality and yours are quite different.
I think we're all Bozos on this bus.
Falcon5232, SCS8170, SCSA353, POPS9398, DS239

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Let's be honest... Far too many jumpers are astonishingly ignorant of their gear. My concern about adjustable parameters would be that jumpers who are clueless could set parameters that make no sense to any of us (including DIVALENT). Given that premature opening of the reserve container can place other people (and aircraft) at great risk, there is a community reason to not allow folks to set their own parameters on their AAD.
The choices we make have consequences, for us & for others!

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Let's be honest... Far too many jumpers are astonishingly ignorant of their gear.



Agreed.

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My concern about adjustable parameters would be that jumpers who are clueless could set parameters that make no sense to any of us (including DIVALENT). Given that premature opening of the reserve container can place other people (and aircraft) at great risk, there is a community reason to not allow folks to set their own parameters on their AAD.



Jumpers can already set offsets on their AAD already, some require you to set it each jump. others until the AAD is turned off. Granted this is not the same as simply raising the firing altitude, as offsets change the low end firing parameters too.

Making a settable default firing height could be added that a jumper could config and 95% would never know or do it because they don't RTFM.

Even so, I can see value in making it a rigger or manufacturer adjustable setting only.
Stupidity if left untreated is self-correcting
If ya can't be good, look good, if that fails, make 'em laugh.

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Jumpers can already set offsets on their AAD already, some require you to set it each jump. others until the AAD is turned off. Granted this is not the same as simply raising the firing altitude, as offsets change the low end firing parameters too.



What concerns me more than the low end firing parameters is the possibility that it may affect the AAD's ability to detect that the jump is over, causing it to remain in jump mode, and not re-zero itself to ground level. I have no idea how each of the units on the market would behave, but I'd be concerned enough to power cycle the AAD before each jump if I decided to do this, regardless of make/model.
"It's amazing what you can learn while you're not talking." - Skydivesg

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>My concern about adjustable parameters would be that jumpers who are clueless
>could set parameters that make no sense to any of us.

Agreed. Any such feature would have to be difficult to use, such that a jumper had to be determined to learn how to do it and then implement it. For example, making it updatable via a PC based programmer would allow people to set their own heights with less risk of a 100 jump wonder coming across that setting and deciding to update it to 2200 feet (because he never pulls lower than 2500.)

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I'm sure it's possible to fuck it up but we all have to trust each other with main and reserve handles and we trust each other to do pin checks and maintain their closing loops so they don't break in the door and kill everyone.

I don't see how customizing an AAD to your jumping behavior is more difficult or dangerous than many other decisions we have to make every time we go to the DZ. Spotting, setting breakoff and pull altitudes and a host of other things need specific consideration and most people can do all those without killing themselves, why is setting an AAD so much different?

You can't dumb down something as dynamic and unpredictable as skydiving to the lowest common denominator. Gear decisions are sometimes life and death. While listening to the procedures and principals that have been written in blood is smart so is recognizing when something isn't working the way it should and trying to make it better or suit it to your needs.

Considering there have been numerous fatalities contributed to AAD's not giving the reserve enough time to deploy means it probably isn't firing high enough. Yes, I know the AAD only cuts the loop and does not "cause" a fatality by firing too low but it likely would have prevented a few fatalities if it fired a few hundred feet higher. How likely is it for a 2 out to kill you? Not too likely for me, I fly large square canopies and pull pretty high so why can't I balance the risk and set my AAD to an altitude more likely to work?

The most important thing to do is plan your skydive around the limitations of your gear, not the other way around. The fatalities don't lie, sometimes it takes more than 750 feet to get a reserve over head, not always but enough to consider a change. It's fact that you have a better chance of your system (AAD and container) working if it fires a little higher, so adjust your procedures and pull a little higher. That's an advantage I would like to have so I'm open to RTFM and adding a few hundred feet so I have the best chance of it working if I need it. If I didn't trust myself to do that I shouldn't trust myself to pack, gear check, pull or a host of other things I must do to skydive another day.

I fit the gear to my skydive not the statistically average skydive. I usually pull at 4K not 2K so it's more likely I'll need the AAD to work, if I haven't pulled by 2 it's likely I won't by 1K. I'd rather have 2 out than 0 if I fuck up that bad.

If you average skydiver cant be trusted to RTFM and program it what if it was a rigger duty? That would prevent most idiots from setting it so wrong that it kills them, yeah? Would that be better? Because the current setting is considered too low by many who have the experience to know so why not change it so it works all the time and then adapt the procedures?

:o

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Considering there have been numerous fatalities contributed to AAD's not giving the reserve enough time to deploy means it probably isn't firing high enough.



Please stop right there. Your supposition is flawed.

Last year, USPA and PIA told us that we have some cases where it seems that the AAD fired high enough, and yet still the reserve did not open in time. Go read their publications. That is what they said.

We had AADs for a long time before we had the problem that the AADs do not seem to be firing high enough.

Something else changed, not the AAD.

What seems to have changed is that there are rigs now that do not seem to be functioning according to the specs that were used to decide how to program the AADs.

The problem isn't in the AADs. It is in the rigs.

When we have rigs that won't deploy in time to meet the performance standards that are required, that's what we should work on.

Now, don't mistake me here. I am not saying that the harness/containers themselves are flawed.

The entire system is not working the way it should. Not just the Harness/Container.

The combination of Harness/Container, reserve parachute, and rigging have combined to create systems that are not working to spec.

If these systems are not functioning to spec, figure out what is wrong with them and fix that.

Then you won't have to mess with the AADs.

Each part of the whole system must work to spec for the desired result to occur.

Find out what is out of spec and why, and fix that. Don't just point the finger at the AAD.

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I'm sure it's possible to fuck it up

I don't see how customizing an AAD to your jumping behavior is more difficult or dangerous than many other decisions

why is setting an AAD so much different?

While listening to the procedures and principals that have been written in blood is smart so is recognizing when something isn't working the way it should and trying to make it better or suit it to your needs.

Considering there have been numerous fatalities contributed to AAD's not giving the reserve enough time to deploy means it probably isn't firing high enough.

Yes, I know the AAD only cuts the loop and does not "cause" a fatality by firing too low but it likely would have prevented a few fatalities if it fired a few hundred feet higher.

How likely is it for a 2 out to kill you? Not too likely for me, I fly large square canopies and pull pretty high

why can't I balance the risk and set my AAD to an altitude more likely to work?

The fatalities don't lie, sometimes it takes more than 750 feet to get a reserve over head, not always but enough to consider a change.

It's fact that you have a better chance of your system (AAD and container) working if it fires a little higher,

adding a few hundred feet so I have the best chance of it working if I need it.

I usually pull at 4K not 2K so it's more likely I'll need the AAD to work, if I haven't pulled by 2 it's likely I won't by 1K. I'd rather have 2 out than 0 if I fuck up that bad.

If you average skydiver cant be trusted to RTFM and program it what if it was a rigger duty? That would prevent most idiots from setting it so wrong that it kills them, yeah?

Because the current setting is considered too low by many who have the experience to know so why not change it so it works all the time and then adapt the procedures?



You make some off-the-wall assumptions here.

You falsely state "there have been numerous fatalities contributed to AAD's not giving the reserve enough time to deploy".

You fail to understand that cutting a loop and a reserve coming out are two independent things.
You're blaming the AAD for what is really some other problem.

You want to "fix" things? Solve the real problem.

You fail to understand the rate-of-descent parameter.

You fail to understand Booth's Law.

You fail to understand that things just don't work "all the time".

You fail to understand ground rush and that a higher firing altitude exposes you to a greater chance of having a 2-out.
-Didn't pull by 2!
-Oh shit!
-Main Dump...ooops 2-out.


All those things have been addressed in the thread.


On top of that...
On the one hand you say you say, "customizing an AAD to your jumping behavior" and later you say, "plan your skydive around the limitations of your gear".
My reality and yours are quite different.
I think we're all Bozos on this bus.
Falcon5232, SCS8170, SCSA353, POPS9398, DS239

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>Also to be considered is a Cypress set to fire at 750ft arms itself at 1200
>ft. Raising it 500 ft means its arming close to 1800 ft.

The cypres arms on the way up, not on the way down. Nothing would have to change to move the firing altitude up.



But doesn't that just open up a different window for "when the AAD won't result in an open canopy for a incapacitated jumper"? While trying to deal with the problem of a snivelly reserve, you've just introduced a "no man's land" between 1200 and 1800 (actually 1700). If someone has an emergency exit within that range and is rendered unconscious, the AAD will not be armed whereas it would have been with the current configuration.

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>If someone has an emergency exit within that range and is rendered unconscious, the
>AAD will not be armed whereas it would have been with the current configuration.

Correct. Although right now the AAD won't fire if you exit at 1200 feet. (Of course that's true whether or not it is armed.)

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I agree but it's much easier to raise the firing altitude 300-500 feet on your AAD than it is to redesign your container. However, I do really like the design of the Basik Seven with no side flaps, maybe things are going that way?

In the mean time though the mist practical solution IMO is to raise the firing height a few hundred feet and adjust you pull altitude accordingly. I'm more asking than stating all this, obviously, I only have 3 seasons in the sport but I'm not all that new to aviation and risk analysis in general. I just don't see why people are so opposed to adding a few hundred feet of buffer to allow your fancy 8 flap bulletproof freefly container to let you reserve PC out. How hard could it be to set your AAD. It only has 1 button ;)

D

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If someone has an emergency exit within that range and is rendered unconscious, the AAD will not be armed whereas it would have been with the current configuration.

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I like to examine all the possibilities as much as the next guy, but how vanishingly small is the probability of this scenario as compared to the advantage of adding a couple hundred feet to address snivel or burbles on a normal AAD activation?

For the same reason I jump off a perfectly good diving board.

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Popsjumper and RiggerPaul you are both very valuable contributors to this forum and I have learned a lot reading your posts. I want you to understand that my reply is meant to challenge my understanding and not yours, I know you got me beat in the department of skydiving knowledge hands down. I am just trying to broaden my understanding by participating in the discussion, I hope you don't think I am treating it as an argument, I'm not asserting that I'm right, just asking why I'm wrong :)
That said,

I think a lot of people resort too much to common standbys like "the AAD doesn't deploy the reserve it only cuts the closing loop, idiot" when they don't want to consider a solution to the problem of a reserve not getting out in time.

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You falsely state "there have been numerous fatalities contributed to AAD's not giving the reserve enough time to deploy".



Bill Booth would disagree with you, albeit he stated it more eloquently here than I did in my previous post.

http://www.youtube.com/watch?v=tQuJr5wuvSw

"I know of 9 fatalities where the AAD fired and the reserve failed to deploy in time in the last 3 years" - BB

"If you have a 1 second hesitation of the reserve pilot chute [after and AAD fire] you die" - BB

"I think AAD would save a lot more people if they were set 300-400 feet higher" - BB. And yes "If you do that you will have more 2 outs" Which would you rather have?

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You fail to understand that cutting a loop and a reserve coming out are two independent things.



From my original post..."Yes, I know the AAD only cuts the loop and does not "cause" a fatality by firing too low but it likely would have prevented a few fatalities if it fired a few hundred feet higher."

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You fail to understand the rate-of-descent parameter.



You mean that the AAD will fire higher if it senses you are going faster? I read the manual but if that's not what you mean I would like to know, I'm here to learn.

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You fail to understand Booth's Law.



I'm familiar with risk homeostasis. It's an interesting and IMO correct theory but if you put too much stock in it you end up taking out your reserve so you are more careful packing you main. A bigger safety margin is still a bigger safety margin. Can you say an extra few seconds to let your reserve PC escape the container and catch air is a bad thing?

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You fail to understand that things just don't work "all the time".



Well screw it then, no reason to try and make it any better?

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You fail to understand ground rush and that a higher firing altitude exposes you to a greater chance of having a 2-out.
-Didn't pull by 2!
-Oh shit!
-Main Dump...ooops 2-out.



I haven't experienced ground rush on purpose, hopefully I won't while my PC is hung up inside my container.

Again, I don't understand why 2 out is more feared than nothing out? I'm sure you have seen the PD article about the likely result of having 2 out, it's not exactly death on a stick, especially with large square canopies (what I jump) And there is a very obvious solution, raise your break off and pull altitude, reset your audible, it's not that hard. If you don't want to fine, leave the AAD how it is now and your system will just be slightly less likely to save you. I'd rather give more than 1 second.

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On top of that...
On the one hand you say you say, "customizing an AAD to your jumping behavior" and later you say, "plan your skydive around the limitations of your gear".



I don't pull low. I jump large square canopies. I have a closed container that likely takes longer to allow the PC to escape and the creator of that container says he thinks AADs fire too low. Therefore it would make sense to set my AAD to fire higher, in enough time to allow my system to deploy, or at least give it more than a 1 second chance.

If you usually pull at 2K then it would be stupid to raise AAD firing altitude, you will just miss out on a little safety margin that I would like to have. If you jump a small elliptical and tiny reserve you might be more hesitant to expose yourself to a 2 out than I would be with my big squares, so maybe you figure you are more scared of 2 out than needing you AAD and it not giving the container time to deploy the reserve, that's fair. You jump differently and you should customize your gear (and AAD) differently.

That's what I mean by customizing to suit you needs, like camera fliers not using an RSL they accept the of a faster reserve for a increased safety margin in an camera entanglement

I would like all the advantages I can have so I raise the firing altitude, pull higher, and jump canopies are behaved in a 2 out situation. It sounds safer to me if I do all 3, no?

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On top of that...
On the one hand you say you say, "customizing an AAD to your jumping behavior" and later you say, "plan your skydive around the limitations of your gear".



By planning around your gear I mean that if you AAD might need to deploy a little higher to ensure the container has time to deploy the reserve then you probably should plan on pulling higher. I can allow it more time to increase the likelyhood I get a reserve overhead by offsetting it. No matter what I do I cannot make my reserve deploy faster. If you plan for it to fire higher it becomes a non issue, you just get an extra safety margin.

So why would it be a bad idea to set my AAD to fire at say 12OO feet instead of 750? Taking into consideration I pull high and have 2 large square canopies that are likely not going to kill me in a 2 out?

Just asking here, its nothing personal. :o

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If someone has an emergency exit within that range and is rendered unconscious, the AAD will not be armed whereas it would have been with the current configuration.



I like to examine all the possibilities as much as the next guy, but how vanishingly small is the probability of this scenario as compared to the advantage of adding a couple hundred feet to address snivel or burbles on a normal AAD activation?



You see it an advantage to activate an AAD higher if a canopy is still in process of sniveling open? :o

Personally, I'd rather have the AAD fire at it's current parameters versus create a 2 out scenario or worse potentially foul on the partially open main by firing higher than need be,

I've scared my AAD and dealt with a two out. Even at the current firing parameters had time to deal with it and find a place to land. No need to push it higher for these scenarios IMO.
Stupidity if left untreated is self-correcting
If ya can't be good, look good, if that fails, make 'em laugh.

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>You see it an advantage to activate an AAD higher if a canopy is still in
>process of sniveling open?

There are indeed some people like that; I've talked to them. Their argument can be condensed down to "well, I'd rather my reserve fire than have my main snivel all the way to the ground." Keep in mind that people who have had AAD's all their lives often see them as must-have devices, and will not consider jumping without the protection they afford. To someone like that, loss of protection even during a snivel is an issue.

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I personally think that the main issue for people advocating higher firing altitudes (with all due respect to BB) is justifying the reasoning. Right now, the reasoning seems to revolve around the instances where an AAD has fired but the person has gone in without an open reserve. So far as I've seen, we haven't actually established the reason for these fatalities. If the loop is cut by the AAD correctly but the reserve doesn't open in the time available, who says it'll be open with an extra second? I'm all for saving lives but if we're going to bandaid this (better to use a bandaid and save some people for sure) we really shouldn't lose sight of the fact that the AAD wasn't the problem. We've then taken a last ditch, hail mary backup device and turned it into a solution to a problem that no one understands.

I think that raising the AAD firing height causes several issues in itself and the higher we go with that firing height, the more people will be affected by the change. The scenarios where people are having two out because their main deployment crossed over at sufficient speed with the AAD firing parameters to cause a two are the outliers statistically speaking. When you move the AAD activation height, you move the curve and we'll start seeing more two out scenarios. When we think about two outs it's nice to imagine that we're talking about happy side by sides or biplanes but we could also be talking about downplanes and entanglements. The more people who have a two out, the more likely we are to get into these ugly two out scenarios.

I think one of the other issues we face is that an AAD is a mechanical (for all intents and purposes) device that fires no matter what once the parameters are met. If someone (foolishly IMO) sets their AAD for 2000ft and then goes on a bigway and is deploying at 2500, it's likely that they'll end up with 2 out with a bunch of people in their airspace and this could lead to a collision.

The main point of all this is that we could be trading the small number of fatalities caused by reserves not opening in time when activated for a whole bunch of other problems without really knowing why.

Having said all that, I'd be ok with raising the general AAD firing height to 1000 but I wouldn't want mine firing higher than that. I think that any variance in base firing altitude (excluding any offset) should be limited to the currently available range. By that I mean that my AAD can be changed from "pro" ~840ft to student ~1040ft (for the Vigil 2) and those altitudes are already available to me and have been duly considered by the designers and engineers. Raising the base height to other values could actually cause issues with the algorithms used (remember, we're not talking offset here) and would have to be investigated by AAD manufacturers before it should be even considered airworthy IMO.

I look forward to corrections because god knows I don't know everything. ;)

edit: To correct myself - here's the wording from the Vigil 2 manual regarding activation altitude (page 10 & 11 if you're curious):
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Therefore a compensation of + 260 ft or + 80 m above the nominal activation altitude was integrated. In PRO mode a programmed activation altitude of 1100 ft or 336 m has been set to guarantee notwithstanding the position, activation at a minimum altitude of 840ft or 256m (real altitude) above the ground.
In a test chamber, the activation in PRO mode will always be triggered at 1100 ft (840 ft + 260 ft) or 336m (256m + 80m) as there is no depression zone.

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I'm sure it's possible to fuck it up but we all have to trust each other with main and reserve handles and we trust each other to do pin checks and maintain their closing loops so they don't break in the door and kill everyone.

I don't see how customizing an AAD to your jumping behavior is more difficult or dangerous than many other decisions we have to make every time we go to the DZ...

***

You have started your argument with an incorrect assumption; I don't do not trust you near my handles, doing a pin check on my gear, nor do I trust that you correctly maintain your gear. We don't know each other that well... And, I can point to lots of examples how each of the items you mention has resulted in a life threatening incident, multiple times.

The reason you do not see how each jumper individually setting AAD operating parameters is potentially dangerous might be that you don't fully understand how AADs work and interact with a variety of skydiving variables.

We do not know there are numerous fatalities attributable to AADs not giving a reserve time to open. Where is the conclusive evidence of that?

"...why not change it so it works all the time..."

The quote above tells me a lot about your opinion on AADs. If only it were that simple... :S

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I'll just touch on a couple of points....

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"I know of 9 fatalities where the AAD fired and the reserve failed to deploy in time in the last 3 years" - BB

"If you have a 1 second hesitation of the reserve pilot chute [after and AAD fire] you die" - BB

"I think AAD would save a lot more people if they were set 300-400 feet higher" - BB.


How many of those 9 were caused by an AAD that did not activate at its programmed altitude, given altitude and descent rates were met?

How many of those delayed deployments were caused by:
-body position
-"container lock"
-packing
-horseshoe
-gear maintenance

You should have, by design, an open reserve by 3 seconds after AAD activation. What are some things that can, and will, delay that?

Raising the activation altitude 300-400 ft will, yes, allow a couple of extra seconds to get around some of those problems but what have you really fixed? Nothing. And there's no surety that one could get around those problems even with a couple of extra seconds.

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And yes "If you do that you will have more 2 outs" Which would you rather have?


I'd rather have gear that's not going to delay my reserve deployment either after the AAD activation or after my manual pull.


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..but it likely would have prevented a few fatalities if it fired a few hundred feet higher."


Given the MORE likely causes of those delayed deployments, I would tend to think not.

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You fail to understand the rate-of-descent parameter.



You mean that the AAD will fire higher if it senses you are going faster? I read the manual but if that's not what you mean I would like to know, I'm here to learn.


No, not at all. Rate of descent is one of the parameters that must be met for the AAD to activate.
Altitude being another.

I'll try to explain this way:
Two scenarios
1. AAD at 750
2. AAD at 1000

You have screwed up and are pulling low.
Your open main is hosed so you breakaway...
If you reach 750 and have not yet acquired speed enough to meet the descent rate parameter, you didn't meet it at 1000 either.
Setting your activation altitude at 1000 would have done nothing for you.

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Can you say an extra few seconds to let your reserve PC escape the container and catch air is a bad thing?


No. I'm saying fix the problems instead of treating the symptoms.

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You fail to understand that things just don't work "all the time".



Well screw it then, no reason to try and make it any better?


Well, nobody is saying that....just trying to direct the efforts in a more realistic direction.


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Again, I don't understand why 2 out is more feared than nothing out?


[facetious, or maybe not]
I might survive a 2-out as a mangled vegetable dependent on others to feed me and wipe my butt.
[/facetious, or maybe not]

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I haven't experienced ground rush on purpose, hopefully I won't while my PC is hung up inside my container. ....


See! You really DO see what one of the main problems are!

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I have a closed container that likely takes longer to allow the PC to escape and the creator of that container says he thinks AADs fire too low.


I see a relationship there. Does anyone else?




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So why would it be a bad idea to set my AAD to fire at say 12OO feet instead of 750? Taking into consideration I pull high and have 2 large square canopies that are likely not going to kill me in a 2 out?



See above. Plus can you say for sure that you will pull high on every jump?

You mention "likely" quite a bit throughout your questioning...almost as if you depend on the "likely" actually happening every time. Please know that "likely" doesn't happen all the time and be prepared for when it doesn't, eh?

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Just asking here, its nothing personal. :o


Of course not...:)
My reality and yours are quite different.
I think we're all Bozos on this bus.
Falcon5232, SCS8170, SCSA353, POPS9398, DS239

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You see it an advantage to activate an AAD higher if a canopy is still in process of sniveling open?



Sorry I didn't make myself clear. I meant sniveling of the reserve. I am another poster in this thread not trying to offend but to understand. I have thought about setting my AAD higher (most recently after watching Booth's interview). I am trying to understand the down side and if that is the rare occurence of exiting a low flying crippled plane and then becoming unconcious, I don't see that down side happening very often. I wouldn't expect my main to be still sniveling at 1200 feet since I pull at 3500, but if I lost altitude awareness and pulled at 2000, I could see the downside of not giving an extra second for the main to inflate. Again, I would rather have the extra couple hundred feet cushion near the hard cold ground.

DZ.COM is a pretty good resource to me for questions like "Why shouldn't I ..." As always, I will check with my real live instructors.
For the same reason I jump off a perfectly good diving board.

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I've scared my AAD and dealt with a two out. Even at the current firing parameters had time to deal with it and find a place to land. No need to push it higher for these scenarios IMO.



So you don't like the idea of altitude to deal with a problem, like a 2 out? I sure would.

The following is not directed at you in particular just a statement:

Like stated, simply raising the firing altitude is not going to deal with the MAIN cause of under inflated/non inflated reserves by AAD fire; low cutaways or some other scenario not reaching speed in time. AAD fires at terminal or close to it at 750 should be plenty in theory.

Popsjumper is right on IMO about that, but I would like to pose another question.

What about changing the perameters of the AAD? After a terminal desecnt the AAD can detect when we slow to a certain speed (pull main). Say 20 MPH, AAD switches itself to "canopy mode", during that mode if the jumper reaches a speed greater than say 30 MPH, instead of the ~78MPH, the AAD activates?

The only drawback to this I can see is CRW perhaps or somehow the AAD malifunctions and on your next jump it activates 2 seconds after you leave the plane (this would be bad). If some kind of programming couldn't solve this then maybe reseting after each jump could be an option, like cocking your pilot chute, this would HAVE to become part of the packing process.

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... AAD switches itself to "canopy mode", during that mode if the jumper reaches a speed greater than say 30 MPH, instead of the ~78MPH, the AAD activates?



Swoopers would have to deal with two out every time they jumped. I may be new to the sport, but from what I'm aware, 30mph is pretty easy to achieve under a fully functional canopy.

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