Argus misfire

[chuckakers 426]

Buddy o' mine had his Argus fire at 2,500 feest last weekend. POV video clearly shows his altimeter indicating 2,100 feet with 2 canopies overhead.

He had just returned from Chicago (to Houston), and there is an altitude difference (but not close to the 1,100 to 1,500 foot misfire he had). He also turned the unit on at the DZ where it misfired, so it should have calibrated to the DZ altitude anyway.

Anyone had this happen to them or have any possible causes on this?

Chuck Akers
D-10855
Houston, TX

[hackish 8]

Not aware of any stories but I assume the unit has or will be sent back for analysis?

-Michael

[SimonBones 1]

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or have any possible causes on this?

Failure to buy a Cypres. Have a nice day

108 way head down world record!!!
http://www.simonbones.com
Hit me up on Facebook

[727_Jumper 0]

great, just when I'm weighing my options for a new AAD

[funfall 0]

First jump of the day? How long had he been back from Chicago? (hours? days?) Could it have been on during the flight back?

(edited to delete altitude difference estimate, after John Rich provided more precise data)

[JohnRich 4]

Airport elevations:
Skydive Chicago, 616 feet. http://www.airnav.com/airport/8N2
Skydive Houston, 235 feet. http://www.airnav.com/airport/37X

Difference: -381 feet.

[727_Jumper 0]

need more data

Id like to know more about what happened..

how did the events unfold?

I cant tell you one thing or another about it, but I have a curious mind, especially since I'm looking at both the Cypres and Argus for my new rig, and I want to understand whats going on (~).

[Skybear 0]

One thing that always concerns me a bit about the Argus is the fact that the user is responsible for changing the battery, and that the battery is some standard off-the-shelf. Insufficient power supply may trigger any electronic sensor device to false readings. And with a standard battery there is less reliability when it comes to rapid temperature changes like in a skydive.

Can you provide any info about the status of the battery in the Argus which was used here?

[azureriders 0]

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Anyone had this happen to them or have any possible causes on this?

An argus in one of our student rigs misfired at ~10,000 ft about 4 years ago. I don't know what the final word was on why, but I do know that the company was more than willing to make things right and then some to the DZO.

They flew a rep out the next weekend to handle the situation.

Not supporting nor bashing, just reporting.

[Neoslim22 0]

sounds like he might have had it on tandom mode? the argus is set to fire at 2500ft in this mode.

[BrianM 1]

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the user is responsible for changing the battery,

No more so than a CYPRES 1 or a Vigil. Your rigger should be checking/replacing your batteries regardless of which AAD you have.

BTW, the batteries are in the main unit, which is inside the reserve container (same place you will find the CYPRES and Vigil batteries) - not exactly accessible to the user if it is not done during the repack.

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...and that the battery is some standard off-the-shelf.
And with a standard battery there is less reliability...

What exactly do you suppose is inside those magic CYPRES and Vigil battery packs???

"It's amazing what you can learn while you're not talking." - Skydivesg

[Skybear 0]

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What exactly do you suppose is inside those magic CYPRES and Vigil battery packs???

I suppose nothing, I just know what I learned on a factory visit. The battery pack has the capacity to work for at least four years, no matter how often you switch it on or off and no matter how many jumps you do and whether you do them in tropic temperaturs near the equator or somewhere in northern Greenland where it is fu...ing cold. My dytter works with standard batteries and they don't do this job in the way a Cypres or Vigil battery does.

So, let's stop the brand war and talk seriously. What was the status of the battery? If it was low it is worth asking what unwanted side effects this can cause. Just for the other users to learn from it possibly.

[billvon 3,058]

>What exactly do you suppose is inside those magic CYPRES and
>Vigil battery packs?

Specific primary lithium cells. Such cells are generally more reliable than a random manufacturer of CR123A cells. Example:

The Panasonic consumer CR123A provides a nominal capacity of 1550mah. Halfway through its life it will produce 2.5 volts during a pulse load to 900ma. At -20C it drops to 2 volts.

The Sanyo consumer CR123A provides a nominal capacity of 1400mah. Halfway through its life it will produce 2.2 volts during a pulse load to 900ma. At -20C it drops to 1.8 volts.

That's just two types of CR123A's. Another manufacturer, wishing to sell their product for less, might sell a 900mah cell, producing 1.8 volts at half lifetime during a pulse load. Is 3.6 volts at 900mah sufficient to fire the cutter? Probably.

At -20C that same 'economy' cell might produce 1.5 volts. Is 3 volts sufficient to fire the cutter? Maybe. Depends on the rating of the cutter and the amount of capacitive storage inside the unit (and _its_ temperature derating.)

Needless to say, that particular battery will also fail quickly and give a low-battery indication.

That's not to say that the Argus battery won't work. But you need to be a LOT more careful about the batteries you buy; Argus batteries don't have the quality control that the Airtec batteries have.

[funfall 0]

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sounds like he might have had it on tandem mode? the argus is set to fire at 2500ft in this mode.

Isn't it 2200 ft? But a good thought. Not hard to imagine that happening, if the user entered "menu" for some reason.

(edited to include quote)

regarding battery quality: Argus manual says: "We recommend the use of Sanyo
(CR123A), Energizer (123 or EL123AP), Duracell (DL123A), Panasonic (CR123A) or Sony (CR123A –CR17345) batteries. The remaining shelf life must be at least six years." I would trust my rigger to follow the recs. And I take responsibility for not counting on it to work with "low battery" displayed.

[hackish 8]

I think anyone with any type of embedded systems design background will quickly tell you that the unit should not just blindly fire if it encounters a brownout. If that sort of thing isn't part of the design and testing criteria then I don't want one of those AADs.

-Michael

[piisfish 140]

[off-topic]at least the cutter cut the loop [/off-topic]

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

[727_Jumper 0]

from the Argus FAQ:

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Standard: 820ft (250 meters) at a fall rate of 78 mph (35 m/sec)
Novice: 984 feet (300 meters) at a fall rate of 45 mph (20m/sec)
Tandem: 2165 feet (660meter) at a fall rate of 78 mph (35 m/sec)
Swoop: 820ft (250 meters) at a fall rate of 78 mph (35 m/sec).

[erdnarob 1]

You shouldn't rely on one isolated case to make up your mind. All AADs have had their problems (bad pressure sensor, cutter with sharp edges at the hole, electrostatic firing, firing when the jumper was doing spiral turns.... and last but not the least, wrong use of the AAD by the owner who often never read the owner's manual or do not understand it). I guess that now more than a million of jumps are made every year using AADs. Statistics are such that few firing cases are not significant. First one has to find the cause of the problem which is generally not that easy.
OTOH AADs are to be used as back up devices only, just like car air bags...You still have the responsibility to be safe. As I said in the mean time, AADs are saving lifes.
DB COOPER #290

Learn from others mistakes, you will never live long enough to make them all.

[rhys 0]

Can you confirm whether or not it was in tandem mode, I know your buddy will be reluctant to admit fault if it was in tandem mode, but the manufacturer will know by anylising the unit.

"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix

[chuckakers 426]

Got more info from the Argus owner today. He confirmed that the unit was not in tandem mode and that none of the "human error" stuff that could have explained it happened.

He said that Argus promptly replaced the unit and the suspect unit has been sent in for evaluation. The company is also reviewing the video.

Chuck Akers
D-10855
Houston, TX

[funfall 0]

Thanks, Chuck. I'm still curious to know if it was the 1st jump of the day, and how long he had been back from jumping near Chicago. Maybe it will turn out to be irrelevent, of course.

[TrojanHorse 0]

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Buddy o' mine had his Argus fire at 2,500 feest last weekend. POV video clearly shows his altimeter indicating 2,100 feet with 2 canopies overhead.

He had just returned from Chicago (to Houston), and there is an altitude difference (but not close to the 1,100 to 1,500 foot misfire he had).

We received this unit only today. The altitude was manually corrected with 1500 feet. The unit activated at an altitude of 2500 feet. In other words this was not a misfire.


***He also turned the unit on at the DZ where it misfired, so it should have calibrated to the DZ altitude anyway. ***

The Argus AAD keeps an altitude correction in its memory even after switch off. Any altitude correction has to be "undone" manually too. (See the manual.)

William
Argus

[bucketlistpilot 1]

I wonder how the APF will spin this one into their bullshit ban on Argus

Ian Purvis
http://www.loadupsoftware.com
LoadUp DZ Management App
admin@loadupsoftware.com

[Skybear 0]

Thanks for letting the community know. Especially the point that the altitude correction stays in the unit after switching it off is interesting. It is a difference to other AADs and underlines the necessity to read the manual and be familiar with such specifics.

[pchapman 279]

So, if the Argus report is correct, the question is, why the device had a 1500' offset applied. That's not common, and certainly not expected for jumping around Chicago. Or was it somehow mistakenly entered when experimenting, without realizing that the altitude correction is retained after turning off, unlike for a Cypres?