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PsychoBroJosh

7 WFFC Vigil (mis?) fires on the Jet

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Just got back from WFFC tonight (Sunday 7/24) and wanted to see if anyone had any info on the 7 Vigils that fired on Perris Valley's DC-9 this morning. The story I am aware of is that the cabin was pressurized after the door was shut and 7 Vigils "fired" the reserves. Does anyone know what the cabin was pressurized to? Did every Vigil on the load fire? I am aware that no other brand of AAD did fire during the pressurization. Did anyone have a Cypress 2 or an FXC on this load?

I am not looking to badmouth Vigil at all here. I am sure we all remember that the Cypress had a few issues when it came on the market and I am all about manufacturers getting a little more competitive with AAD's. The result is typically a better product with a cheaper price for the end user. Just looking for any more info on this incident regarding the specifics that caused these to fire. I would love to hear a firsthand account from anyone on the load or from the Vigil people themselves about what happened.
Josh K.
"Rice is great when you're hungry and want 2000 of something"
Mitch Hedberg '68 - '05

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this happened on the world record jumps too. the vigils fired the cypres 1's turned off and wouldn't wake up and the cypres 2's were normal.

I hope vigil can sort these issues, they are no relavant for most skydives but not very good publicity.
"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix

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I was on the first load (Saturday). It seemed that we went down in altitude 300 feet and stayed there for a long time before we even got to the end of the runway (My altimeter returned to 0 after the jump, confirming the -300 feet altitude in the cabin)The cabin altutude stayed low during the climb until they depressurized at about 8K, with the resulting fogB|. I am surprised they haven't gotten it figured out yet how to keep the air conditioning pacs on without pressurizing.

I am wondering if a cypres will recalibrate itself to a lower elevation during the period the plane was pressurized to below DZ elevation, effectively meaning that it would fire 300 feet lower than normal. I remember that the owners manual says to not descend below the take off altitude (plateau/canyon type scenario). My cypres (old version) was reading 0 after the jump. It would be interesting to know how long it takes before they will adjust to a new ground altitude.
People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

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I am wondering if a cypres will recalibrate itself to a lower elevation during the period the plane was pressurized to below DZ elevation, effectively meaning that it would fire 300 feet lower than normal. I remember that the owners manual says to not descend below the take off altitude (plateau/canyon type scenario). My cypres (old version) was reading 0 after the jump. It would be interesting to know how long it takes before they will adjust to a new ground altitude.



That's a great point I failed to think about here...

Someone mentioned that it operated as designed... I did read the article about the world record attempts and the misfires that occured on that jump as well and I believe that it did go into some detail as to the perameters the Vigil uses to fire that initiated the misfires on that load. I am, unfortunately, unable to locate my copy of "Skydiving" with that article. Can someone explain exactly how the situation in the cabin fooled the Vigils into firing or tell me where to find that info? I can understand if the pressurization brought the AAD's above a firing altitude and then by depressurizing rapidly made it believe that it needed to fire, but I believe the pressure in both instances was under a few hundred feet of reality (I may be wrong here, it was a while back when I read the article regarding the record attempt firings). If that was the case, what variable actually told it to fire?
Josh K.
"Rice is great when you're hungry and want 2000 of something"
Mitch Hedberg '68 - '05

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hi guys !

very interesting ! as a vigil owner i can't wait to read why they popped !
does anybody know what happened with the pro-tracks datas on those loads ? i guess that the protracks don't like too much the variations in pressurization.

cheers !
--------------------------------------------------
I never used 2 rocks to start a fire ... this is called evolution !

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http://www.dropzone.com/cgi-bin/forum/gforum.cgi?post=2063517#2063517

read this peeps. the information is out there. anytime you do something out of the norm then chances are there's a little more to it than just being a "normal" skydive.

hope this helps

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WHY the hell are they pressurizing the a/c at all???
They know there are skydivers on board,and they know most skydivers wear AAD's. An AAD has one source of data to determine it's altitude and velocity. Jacking around with pressurization is an accident waiting to happen.
"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

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> WHY the hell are they pressurizing the a/c at all???

Because some aircraft are designed to do that, and will pressurize when configured for 'normal' operations. So you have to change checklists/operating instructions, which can take time and effort.

In addition, as in the Thai C-130, a failure can cause pressurization anyway.

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>I am sure we all remember that the Cypress had a few issues when it
>came on the market and I am all about manufacturers getting a little
>more competitive with AAD's. The result is typically a better product with a
>cheaper price for the end user.

I just emailed Vigil and asked them about this. They think their AAD's worked properly, and will not be making any changes to reduce the chances of it firing in a pressurized aircraft.

So if you do think you may jump a jet, or a C-130, a Cypres 2 may be a better choice. I know I'll be using one at the next World Team.

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I was told they turned on the AC which changed the pressure in the plane.

I've been told all of the jumpers with Vigils that fired were offered the useage of Cypres2 units from SSK which was onsite for the convention. They were also refunded their ticket and offered a second jet jump.
Yesterday is history
And tomorrow is a mystery

Parachutemanuals.com

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I can't believe that people would do either of two things; wear an AAD on a pressurized aircraft, pressurize an aircraft with AAD's aboard.

Bill what is it about the Cypres2 that safeguards it from this situation?
"I encourage all awesome dangerous behavior." - Jeffro Fincher

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I can't believe that people would do either of two things; wear an AAD on a pressurized aircraft, pressurize an aircraft with AAD's aboard.

Bill what is it about the Cypress2 that safeguards it from this situation?



I'll bet the cypres2 just turns itself off. ;)

rm

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> WHY the hell are they pressurizing the a/c at all???

Because some aircraft are designed to do that, and will pressurize when configured for 'normal' operations. So you have to change checklists/operating instructions, which can take time and effort.



I'm not directing this at Bill, but does anyone know how can they not have already settled on a procedure that works during the trials they did with the FAA before flying out to Rantoul. How can they not have settled on a procedure that works after the first loads on Saturday?

Isn't it common for a jet to be providing cooled air from its own pacs (APU powering them) when the door is open, loading passengers? I would really like to know more, such as don't the pilots have full control of the outflow valve positions? They should be able to control the cabin altitude in a full manual mode, as if the automatic system failed, right? I tried to politely ask one of the pilots myself, but it was obvious he didn't really want to discuss details. I probably wouldn't either, because I think it is embarrasing that they hadn't figured it out.

To emphasize again, this is not just an issue of preventing reserve activations, it also involves whether the AADs will work correctly if needed.
People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

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>I am sure we all remember that the Cypress had a few issues when it
>came on the market and I am all about manufacturers getting a little
>more competitive with AAD's. The result is typically a better product with a
>cheaper price for the end user.

I just emailed Vigil and asked them about this. They think their AAD's worked properly, and will not be making any changes to reduce the chances of it firing in a pressurized aircraft.

So if you do think you may jump a jet, or a C-130, a Cypres 2 may be a better choice. I know I'll be using one at the next World Team.



I am getting that feeling too. I have more faith in the tried and true nature of the Cypres units at this point.

I would hope that someone from Vigil would explain why this is considered "normal operation". I think people may be more inclined to use their product if they understood what happened in these instances and how to avoid them in the future. Without any explanation as to why it happened, it will happen again and I think sales would suffer as a result of the negative publicity and the possibility of it happening to you.
Josh K.
"Rice is great when you're hungry and want 2000 of something"
Mitch Hedberg '68 - '05

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I was told they turned on the AC which changed the pressure in the plane.

I've been told all of the jumpers with Vigils that fired were offered the useage of Cypres2 units from SSK which was onsite for the convention. They were also refunded their ticket and offered a second jet jump.



I dont think that there were 7, but 5 or 6. Yes they got another ticket for the jet and had their reserves repacked for free. Yes SSK donated cypres2's to those people to use for the rest of the convention if the person wanted to. Great job on their part!

I think Cypres's (probably both 1 and 2s) and vigils were the only AADs on the plane. I haven't seen any FXC at WFFC yet this yr (not that there may be some).

Where is my fizzy-lifting drink?

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This from Airtech about the Thailand situation:

"CYPRES 2, due to its advanced technology, is able to analyze and deal with this situation better. There was no reason to go into "lock-out" mode as the unit was able to determine that there were no permanent adverse afects, and thus could be used on further jumps.*

*Always switch CYPRES off and on priior to the next jump after any overpressure situation (skydiving altimeter goes below "0")."

http://www.cypres-2.com/cypres_news_letter_feb_2006_c.pdf

That's pretty much all I'd be able to understand anyway although "due to its advanced technology" is a pretty vague statement.
"I encourage all awesome dangerous behavior." - Jeffro Fincher

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>(sundevil)I'm not directing this at Bill, but does anyone know how can they
>not have already settled on a procedure that works during the trials they
>did with the FAA before flying out to Rantoul.

I would guess because there aren't many commercial passenger airlines flying jumpers. It's uncharted territory. Absolute cabin altitude has never been an issue before on passenger jets, and being off +/- 1000 feet is no big deal. Unless you can't open the doors in Denver, but that's easy to fix at that point.

>They should be able to control the cabin altitude in a full manual mode,
>as if the automatic system failed, right?

Right - but that mode is not often used.

>I tried to politely ask one of the pilots myself, but it was obvious he didn't
> really want to discuss details. I probably wouldn't either, because I think it
>is embarrasing that they hadn't figured it out.

Or was afraid it would get misrepresented on the internet. That's happened before.

>(DJL) I can't believe that people would do either of two things; wear an
> AAD on a pressurized aircraft, pressurize an aircraft with AAD's aboard.

Many people will not jump without AAD's, even if they are jumping aircraft (like C-130's, 727's and DC-9's) that can be pressurized.

>Bill what is it about the Cypres2 that safeguards it from this situation?

It can detect the overpressurization as an impossible, out-of-bounds condition and not fire. Cypreses in general are less likely to fire during physically impossible changes in pressure altitude.

(Edited to change notes on Cypres-2 operation.)

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I was on load 3 on Saturday. I have a Vigil which was turned on because it simply didnt occur to me that they would be pressurizing the plane for a flight to 14000 ft where they would then be opening the door.

My Vigil didnt fire. No vigils on my flight fired and I know for a fact that my buddy on the same load also has a Vigil so there was more than one on board.

Is it safe to assume that things were done differently on different flights?

It seems fairly easy to asssume that they must have been following a different procedures on different flights since a bunch fired on one flight but none on any of the others.

What did they do differently on that one flight?
__

My mighty steed

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What did they do differently on that one flight?



Chris, we were on the same load... I was the guy in the wing suit. I'm suspecting the rear door probably stayed open until we were ready to move on our load and the cabin wasn't pressurized at any point on take off/ climb. other loads i suspect that they depressuried at different points or had the rear door closed when they were performing their checks.

Where is my fizzy-lifting drink?

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>It seems fairly easy to asssume that they must have been following
>a different procedures on different flights since a bunch fired on one
>flight but none on any of the others.

Or the same procedure at a different temperature/engine speed/APU state/door state. Like I said, no one's ever done this before (skydiving from a DC-9.) I'd expect it to take a while to iron out the details. Which is one reason I like the cypres 2 in such cases.

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There is still the greater issue of whether the reference ground elevation gets reset, as on the first load that went down 300 feet for a significant period before take off. I wonder how long is required for the system to 'recalibrate' to what it might think is a new DZ ground elevation/pressure.

Because my old cypres read 0 after the jump, I think it did not recalibrate, as I believe the display would have shown something different had I landed 300 feet above what it thought was the ground. Even though it read 0 after the jump, I turned it off/on again.
People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

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