Why isn't there an AAD with adjustable firing altitude?

[davelepka 4]

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NO one has ever explained (to me anyway) why AAD firing cannot be raised to 1000 feet

It can. User can adjust that if they want.

Why isn't it the 'default' mode from the factory? There are several reasons why that change hasn't been made.

One of them is that 750ft has worked very well for the most part. For many years there were no reports of AAD fires without successful reserve deployments. In many of the cases that have come up recently, there has been suspicion that the real problem was overly tight reserve containters or ineffective reserve PCs (or a combination of both) that lead to reserve deployment delays. The AADs worked as they were supposed to, they fired at the intended altitude, the problem might have been with the rig. The solution in that case does not lie with the AAD.

Another thought is that the min pull altitude has not changed from 2k for many years, however the average altitude loss during opening has gone way up. Canopies open slower these days, and if you still dump at 2k, you're getting closer to a 2-out as your canopy snivels you down lower then you planned. If you raise the AAd firing altitude, you slim that margin even further.

I think the bottom line is this- an AAD is a back-up device, and is designed to work in as many scenarios as possible, with the over-riding design goal being to 'do no harm'. You can adjust the firing perameters all over the place, but you end up increasing the risk of an unintended AAD fire, and we all know that if that happens at the wrong time, can do quite a bit of 'harm'.

AADs are fairly good these days. It's rare that they fire when they're not supposed to, and in most cases they do fire when they are supposed to. Those are good odds for a back-up device that only comes into play after the jumper has made one or more fairly serious errors in judgement.

[diablopilot 2]

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NO one has ever explained (to me anyway) why AAD firing cannot be raised to 1000 feet. It may or may not have made a difference on this occasion.. but I am tipping it would have.

Send some more abusive PMs I get off on them.(not really but I am used to them)

I would have thought simple logic.. may be a problem with AADs firing too late answer increase height. anything else I can help you with. (Joke)

Every model of Cypres, and Vigil have allowed people to do this already. Please read the manuals and understand how your equipment works before jumping or simply guessing at this stuff.

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You're not as good as you think you are. Seriously.

[DougH 270]

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If we wanted to be totally safe we wouldn't jump just post about it on dz.com

Greg has got that one just about covered.

"The restraining order says you're only allowed to touch me in freefall"
=P

[piisfish 135]

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NO one has ever explained (to me anyway) why AAD firing cannot be raised to 1000 feet. It may or may not have made a difference on this occasion.. but I am tipping it would have.

Send some more abusive PMs I get off on them.(not really but I am used to them)

I would have thought simple logic.. may be a problem with AADs firing too late answer increase height. anything else I can help you with. (Joke)

Every model of Cypres, and Vigil have allowed people to do this already. Please read the manuals and understand how your equipment works before jumping or simply guessing at this stuff.

actually it is/was not exactly a "increase firing altitude", but offsetting for a different landing altitude...

scissors beat paper, paper beat rock, rock beat wingsuit - KarlM

[diablopilot 2]

Works in the same way.

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You're not as good as you think you are. Seriously.

[piisfish 135]

not really. The affect on the "higher altitude" would be correct. Not the one on the "lower" altitude. Cypres for example will not fire under around 50m. This will also change relative to your 0. Also Vigils used to save you when you went under the surface. You would now be landing below the ground you gave to your AAD.

scissors beat paper, paper beat rock, rock beat wingsuit - KarlM

[diablopilot 2]

Increase firing altitude = instruct unit to fire at a lower barometric pressure.

Offset for higher MSL landing area than starting point = instruct unit to fire at lower barometric pressure.

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You're not as good as you think you are. Seriously.

[evan85 0]

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Increase firing altitude = instruct unit to fire at a lower barometric pressure.

Offset for higher MSL landing area than starting point = instruct unit to fire at lower barometric pressure and to lock out and no longer fire at a lower barometric pressure as well.

You missed a spot. I fixed it for you.

All units have a "shutoff" altitude (generally quite low; e.g. Cypress 2 expert is 130 ft.), under which the AAD will not fire. Say you wanted to be extra careful and set your offset for 500 ft. up. Guess what? Now your Cypress will shut off at 630 ft. (or whatever it interprets to be 630 ft.) and not fire below that altitude no matter what. This is why you should not use LZ offset to increase firing altitude, and why Cypress 2's now offer this functionality separately: so you can change the altitude at which the AAD will fire without changing that altitude at which it shuts off and will not fire.

[ksaylor1 0]

If you truly have 79 jumps and 1 year in the sport, there's hope for us yet. At least some newbies know how their equipment works. I will remind you that it's CYPRES, not Cypress. It's a CYbernetic Parachute RElease System, not a tree.

Ken

[evan85 0]

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If you truly have 79 jumps and 1 year in the sport, there's hope for us yet. At least some newbies know how their equipment works. I will remind you that it's CYPRES, not Cypress. It's a CYbernetic Parachute RElease System, not a tree.

Ken

Right you are, Ken. I was being so careful not refer to the Mediterranean island that I added an extra s

My stats are current. Appreciate the kind words. You're absolutely right -- the more knowledge that's out there (both within the community and without), the better for all of us.

[gowlerk 1,912]

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Your posts are getting ridiculous, John. Everyone's heard it before

I'm willing to go on record as being with Chuck on this. It's kind of sad to watch a true pioneer of the sport slowly turn himself into crotchety old man. Even if he is correct, his approach is wrong.

Ken Gowler

Always remember the brave children who died defending your right to bear arms. Freedom is not free.

[ChrisD 0]

That crotchety "old man" like so many of us old ones,.....

is trying his damndest to save your ass! or some unknown kid.


Kind of reminds me of the ending in that movie where they pile up little piles of rocks and plant trees at the end????

I don't care if Billy boy and Johnny throw rocks at each other across their shared parking lot, till the cows come home, they and countless others are hearos to me!

But what do I know, "I only have one tandem jump."

[gowlerk 1,912]

ChrisD

That crotchety "old man" like so many of us old ones,.....

is trying his damndest to save your ass! or some unknown kid.


Kind of reminds me of the ending in that movie where they pile up little piles of rocks and plant trees at the end????

I don't care if Billy boy and Johnny throw rocks at each other across their shared parking lot, till the cows come home, they and countless others are hearos to me!

I gotta agree with this as well. Oh well....

Always remember the brave children who died defending your right to bear arms. Freedom is not free.

[kallend 1,623]

Getting back to the original question:

If I were an AAD manufacturer who had very carefully analyzed the scenarios "needing" an AAD fire, optimized the algorithms, etc., I wouldn't want any random skydiver messing with them.

The people who believe in "The 45 degree Rule", that you should disconnect an RSL before cutting away if in a spinning mal, that wearing a GoPro on your helmet when you have 55 jumps is a good idea, etc. come to mind.

...

The only sure way to survive a canopy collision is not to have one.

[chuckakers 370]

ChrisD

That crotchety "old man" like so many of us old ones,.....

is trying his damndest to save your ass! or some unknown kid.

Wrong. He's defending his design ideas just like he's done his entire career.

John has always had the need to do things differently and then dis every other design out there. Just his way I guess, but it's become a broken record.

Chuck Akers
D-10855
Houston, TX