Suunto Vyper **SERIOUS BUG** in CNS O2 computation

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I could not do the dives that I do today using only tables.

At least not the way they're taught by NAUI/SSI/PADI, etc. In fact, I am "off the charts" regularly on my tables (I do run them as backup) when I do my dives, and since nobody seems to be willing to publish the "radical" ways that people talk about computing on-the-fly NDLs and deco schedules, there's no reason to believe they are anything other than one person's view into what has (so far) worked for them.

I have had timing devices and even a depth gauge fail underwater, so I don't buy the "more likely to fail" argument either. An algorythm bug is ALWAYS there - one thing I've learned from being a systems engineer and programmer for two decades is that while the sequence to "tickle" a bug may be obscure, once found its repeatable - and reliable in causing the malfunction.
 
I've thoroughly enjoyed this, but I hate seeing that lame title about some mysterious and serious bug that no one seems to have ever actually experienced while diving sitting atop the message board so I'm not gonna comment any more on this matter because nothing will come of it besides Karl having a stroke worrying about it or a CNS hit from pushing so hard... I hope you've enjoyed it as well Karl and I hope you find a way to take those tables with you. just make sure you have enough lift to get back up with them.
 
Fact is, you pushed too hard. Your mistake in letting it drop below 107'. You did violate the ascent rate... thats what the little blue diamond is for. You went from 15' directly to the surface, your graph clearly shows that.

No, the diamond means you INSTANTANEOUSLY violated the ascent rate, and when you are surfacing in 6' seas you WILL DO THAT at the end of the dive. That surge was from TEN feet, not 15, and was caused by the sea state. It is why I drifted down some during the original safety stop, and why the diamond is there.

The CNS shot I showed you was from the DEEPEST PART of the dive. The marker is CLEARLY visible. Anything that happened AFTER THAT didn't happen YET! So how does that "diamond" figure into the INVALID CNS CALCULATION, SINCE IT WAS IN THE FUTURE?

Whatever you're smoking, its gotta be illegal.

You say your average was only 104. The suunto MOD (again, MAX) is 107'. Don't push the limits and then cry when you fall over the edge and get caught doing it. It penalized you. In violating its MOD, you also went over the 1.4 PO2 and that causes everything to be refigured.

No, it does not. Go run the sims yourself. A momentary incursion into the PO2 alarm does not penalize you. Now if you STAY THERE, yes, it will. But a momentary incursion will NOT.

Go ahead and try it in the simulator.

The graph CLEARLY shows the spike, which is LIKELY from me re-slinging the computer (which is on a console) from my face to my side. Swimming horizontally, it will fall below the plane of your body by a foot or so in the motion to reclip it, and that's exactly what it showed.

If you persist in calling me a liar in that this momentary (literally, seconds) incursion ONE FOOT below the MOD did NOT cause the CNS graph to spike, I'll post the proof of THAT in an image with the marker IMMEDIATELY following the spike. There is ONE BAR present on the CNS graph at that point. ONE. Not two or three. ONE.

No matter how little the error in your profile, it counts. It may not have shown up instantly, but it was in there you can bet on that. You keep on going back to the tables... why can't you remember that the suunto doesn't work off those tables? That is so simple to remember... It sets out the guidelines, you just have to follow it... and you clearly didn't.

Horsefeathers. Again, go to 107', WITHIN THEIR GUIDELINES FOR 32% and in 15 minutes you will tox out. I showed you an example with LESS depth but STILL an invalid computation.

THAT PROFILE IS 100% WITHIN THEIR GUIDELINES AND I HAVE DEMONSTRATED THAT IT IS REPRODUCABLE IN A REAL DIVE.

It is an ERROR.

Your ascent also wasn't that glorious as you seem to think. Suunto recommends your safety stop be at 20' I believe... Show a screen shot at the end of the dive...

Suunto recommends that you stop between 10-20' for 3-5 minutes. I did. You want the shot from the end of the dive, I'll post that for you. Its right here:

sdm3.jpg


Note the following:

1. No ascent alarm (2 bars on the ascent meter.)
2. 3 bars (improperly computed) for the CNS loading.
3. A CLEAR safety stop timer.

Any more questions? You can retract calling me a liar any time you find it convenient. Like now.

Sell the vyper or stop wining... You had a pretty good surface obligation with that dive as well...

Irrelavent to the point at hand, which is that (1) I did not violate the computer, (2) I made a proper safety stop, as defined by the computer, and (3) I did not violate the ascent rate; the flag on the end of the dive was caused by surge.

You're full of it Jamiei. I recall this dive and EXACTLY what happened during it. It is not a "foggy, hazy, narc'd memory."

Fact is that the computer miscomputed the CNS O2 loading. That's a FACT.

You said it was on 30% nitrox...

No, the 107' dive was on 32%. The later profile I posted was on 30%.

why not use that on the 107 foot dive? You foolishly push the limits when there's no reason to.

Horsefeathers. A PO2 of 1.35 is not "pushing the limits." Suunto builds enough conservatism into their computers that diving close to THEIR computer's limits is actually VERY conservative indeed. Unlike some of the other computers on the market, there is no reason on God's Green Earth to not dive a 32% mix to 107', because they have already computed that mix as 33% rather than 32%! This is especially true if the mix actually measured at 31.something%, and you set the computer to 32% (as you should.)

In truth Suunto is giving you AT LEAST one full percent of extra conservatism, and up to TWO percent, since you always round up!

Your actual time at depth was also about half that of the other dive... and you never violated the MOD... thats a big deal for the computer and your safety and you don't seem to realize that. Why not compare apples to apples since you have the ability? Take both down with you on the 107' 32% dive... Heck, there's no way to tell what mix you had by that screen shot either...

So now you're going to call me a liar?

How many times do I have to prove you're full of it?

I'd take the Vyper with me on my next dive, but I don't happen to have a handy wrist strap for it (its in a console no longer on my primary reg set.) I will see if I can reasonably easily detach it from its console and put it in my pouch - if I can do that without risking losing the computer, I'll see if I can fill your bill - it shouldn't be that difficult.

quote:
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Yes, I was at depth for about 17 minutes. So?
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So you were there more than the 15 you claim that it took to cause the problem.

Yes, and I wasn't at 107' either. Exactly how much of this thread have you FORGOTTEN? Did you FORGET (conveniently) that I have noted that in the simulator a couple of feet - but still within the MOD - makes a HUGE difference in how big this error in computation actually is?

Oh, you did? Or did you omit it because you wanted to flame me and bothering to recall the truth would destroy your argument?

quote:
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There is no violation on the ascent
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Why the nice little blue diamond??? Thats a no no The ascent alarm went off at 10', not 8 or 6 or whatever...

Yes, and 10 - 8 is 2, right? Below 3. Duh. There were roughly 4' seas out that day. Surge does this Jamei. I've explained that. If you don't understand how it will produce a FALSE ascent alarm on the terminal phase of the ascent in the log, then you need to get out and actually dive in real open water, where there are these things called WAVES.

quote:
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No, I did not. I said that if I dove to 107' and sat it would give me an O2 alarm at 15 minutes. I did not do that. The average bottom depth on that dive was between 104 and 105'.
-------------------------------------------------------------------------------

If you haven't made the dive, you don't know a thing about what it would and wouldn't do.

Oh horsecrap.

How about this Jamei?

Are you willing to take a wager on this?

I'll find a pressure pot, and do the dive "in the pot." That way you can rest easy that nobody is going to ACTUALLY tox, and we will have a nice, square profile - no wobbling, no games, no possible violations.

What 'ya think big guy? Do you have the 'nads to back up your bluster? I have multiple profiles here in my log that say that the Vyper miscomputes CNS loading, including the one I posted. You say that its entirely my fault that it "penalized" me, despite the posted evidence that you're full of it.

How much of your hard-earned money will you put up to back your crap? Zero? Or do you have the courage of your convictions?


What false claims have I made?

Oh, let's see - oh never mind, I listed more than a few of them right here in this post.

You sure know how to jump through the hoops to put a spin on things. But you cry when someone sees through it.

Put up or shut up.

What 'ya say, big guy?
 
Genesis once bubbled...
I could not do the dives that I do today using only tables.

At least not the way they're taught by NAUI/SSI/PADI, etc. In fact, I am "off the charts" regularly on my tables (I do run them as backup) when I do my dives, and since nobody seems to be willing to publish the "radical" ways that people talk about computing on-the-fly NDLs and deco schedules, there's no reason to believe they are anything other than one person's view into what has (so far) worked for them.

See thats my point, your a smart enough person that you should be cutting your own tables. Why dont you use one of the many programs available as your starting point. Do a bit of research, get to know the methodology. You would be better off in many ways, and safer!
As far as the on the fly stuff, I guess your talking about the old Navy Table 120 rule. Well thats great for light single tank reef dives, but very limiting, I would think your a bit past that by now.
Shoot, you got enough spare time now that you should be doing Deco Theroy up the wazoo!!!

Dave
 
George Irvine figures his own tables.

:)

Brules
 
jamiei once bubbled...
You did violate the ascent rate... In violating its MOD, you also went over the 1.4 PO2 and that causes everything to be refigured. .... Suunto recommends your safety stop be at 20' I believe... . If you push the limits you can tox out... thats why they are called limits... rrrrriiiiiggggghhhhttttttt..... you get that?

You said it was on 30% nitrox... why not use that on the 107 foot dive? You foolishly push the limits when there's no reason to. Your actual time at depth was also about half that of the other dive... and you never violated the MOD... ..
So you were there more than the 15 you claim that it took to cause the problem.

Why the nice little blue diamond??? Thats a no no The ascent alarm went off at 10', not 8 or 6 or whatever...

What false claims have I made?

I don't know about false claims Jamiei, but you sure have brought up a lot or irrelevant junk.

Genesis has highlighted a condition under which the Suunto gave results other than what he expected on CNS clock calculations.

Specifically, he has stated that in a simulator mode, the CNS clock accelerates to 10 times NOAA rates, while still 1' or 2' below the displayed MOD, and 1' to 2' below the 1.4ppO2 alarm point.

He also has some real dive results, that while not completely clear, tend to confirm that the Vyper actually performs in the same way on a real dive.

Jamiei: ascent rates, whether or not this is an agressive dive, whether or not Genesis did his safety stop where you suggest have nothing to do with the CNS clock, and just tend to confuse the issue.

Genesis: Correct me if I'm wrong, but it appears that you have 3 complaints about the Vyper.
1. Accelerated CNS clock starts at a couple feet before MOD alarm.
2. The Vyper allows only 1/10 of NOAA limits at ppO2 greater than 1.4.
3. 107' MOD for 32% rather than 111', or phrased the other way, the "1.4" MOD for EAN32 is really set at 1.358.

Here's my take on the above:
1. A problem. Minor. In the direction of being conservative, but still incorrect since the clock shouldn't go to warp speed before MOD alarm. I'm very curious as to Suunto's response to your email about this.
2. It's a Suunto. They are known for being conservative. The manual says that they are very conservative above 1.4 MOD. I don't see where you have a valid complaint on this one.
3. If you enter O2% in only integer numbers, there has to be some way to handle the rounding off. I think you don't understand the operation of your computer. If you measure 32.9%, Suunto says to enter 32%. They then round up to 33% to calculate MOD, and round down to 32% to calculated N2 loading. Very reasonable algorithm, and the Vyper is working as documented. I don't see where you have a valid complaint on this issue.
 
Genesis: Correct me if I'm wrong, but it appears that you have 3 complaints about the Vyper.
1. Accelerated CNS clock starts at a couple feet before MOD alarm.
2. The Vyper allows only 1/10 of NOAA limits at ppO2 greater than 1.4.
3. 107' MOD for 32% rather than 111', or phrased the other way, the "1.4" MOD for EAN32 is really set at 1.358.

Here's my take on the above:
1. A problem. Minor. In the direction of being conservative, but still incorrect since the clock shouldn't go to warp speed before MOD alarm. I'm very curious as to Suunto's response to your email about this.

Actually, no, its not minor, in that you have no warning that it is occurring. I have been able to show from careful review of a real dive that it does happen. If I had been a couple of feet lower and "flatter" in a real profile it would have been more obvious, but it DOES happen.

2. It's a Suunto. They are known for being conservative. The manual says that they are very conservative above 1.4 MOD. I don't see where you have a valid complaint on this one.

Actually, that's not quite true. If you set 1.5 then it doesn't "warp speed" you until you exceed THAT!

The problem with (1) and (2) is that its inconsistent. I can live with the acceleration past the setpoint, so long as I am warned it is happening, and it only happens beyond the setpoint. That's what the manual says it does.

What it actually does is accelerate BEFORE the setpoint is reached, due to a bad calculation, which means that I cannot "trust" the CNS loading display. That's bad, in that it destroys the validity of the measurement that it purports to make.

Quite honestly, IMHO the "warp acceleration" is improper until you exceed 1.6, as there are NOAA guidelines for 1.5 and 1.6 exposures, but I can live with that, as its (1) documented, and (2) so long as it is actually implemented as it is documented I can deal with it.

3. If you enter O2% in only integer numbers, there has to be some way to handle the rounding off. I think you don't understand the operation of your computer. If you measure 32.9%, Suunto says to enter 32%. They then round up to 33% to calculate MOD, and round down to 32% to calculated N2 loading. Very reasonable algorithm, and the Vyper is working as documented. I don't see where you have a valid complaint on this issue.

I don't have a complaint on this issue; I'm aware of this and have no problem with it, as it is within the generally accepted measurement error. This is actual, true conservatism and I'm fine with it.

Finally, it appears that while the Vyper is affected, the Vytec is not, and according to Jamei the Cobra is not (assuming he really did test it - I don't have one handy to check out myself.) I know the Vytec is not, because I've done similar dives (but not quite identical) with the Vytec and have not tripped the acceleration, and I cannot reproduce it on the Vytec in simulator mode.
 
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