Nitrox Class Without Tables or Math...OK?

[Soggy]

you keep switching issues on me.

diving nitrox on a computer is just as safe as diving with tables or the math.

show me how that is not true.

so far, not one of you guys can show me that. you just keep shifting the argument
to other areas.

One more time, Andy...

If the computer supplies NDL/MOD/CNS information due to malfunction or user error, without at least a modicum of understanding about the underlying tables/math, you might not notice and continue on your merry way following the bouncing dot. Electronics underwater can malfunction.

I don't believe anyone actually said that, armed with the knowledge that a nitrox class *should* provide you, diving a computer is dangerous, just that without that knowledge, the computer could trick you just like Manbearpig would before he lured you into the Cave of Wonders and ate you alive.

 

[H2Andy]

ok...

let me try again:

before the dive, i check my MOD and NDL

i know that my dive is going to be to 70 feet for 40 minutes

that's the same knowledge the tables/math would give me

if the computer starts to fritz on me, i will know that based on my planned
profile.

how would knowing how to use math or the tables make me safer?

AND

even using the tables, i'd still have to use a watch and a depth gauge.

what if that malfunctions? it's telling me i am at 60 feet but i am in fact
at 80 ... how can you catch that malfunction?

AND

you guys talk about computers as though they spontanously break down
every other dive. i have been diving for six years and i am yet to see
a computer malfunction, either mine or a buddy's. yes it could happen,
but it's a rather remote possibility. and if it DOES happen, your awareness
of your plan (70 feet for 40 minutes) should get you out ok.

methinks you exagerate the "risks" of diving with a computer and not knowing
math or the tables.

 

[Soggy]

How are you checking your MOD and NDL? Are you sanity checking the computer against itself? That's not particularly productive.

ok...

let me try again:

before the dive, i check my MOD and NDL

i know that my dive is going to be to 70 feet for 40 minutes

that's the same knowledge the tables/math would give me

if the computer starts to fritz on me, i will know that based on my planned
profile.

how would knowing how to use math or the tables make me safer?

 

[H2Andy]

How are you checking your MOD and NDL? Are you sanity checking the computer against itself? That's not particularly productive.

you turn the computer on, and it tells you. it's at its core program. it can not
be changed, nor it can malfunction.

it's foolproof.

it's the basic tables burned into its chip, displayed electronically.

how much more far fetched can you get?

 

[Thalassamania]

Ferrari 612 Scaglietti F1

The 2006 Ferrari 612 is a 2-door, 4-passenger luxury sports car. The Scaglietti F1 is equipped with a standard 6.0-liter, V12, 540-horsepower engine that achieves 10-mpg in the city and 17-mpg on the highway. A 6-speed automatic transmission with overdrive is standard. The 2006 Ferrari 612 is a carryover from 2005.

 

[H2Andy]

yes, but does it come with a back-up engine? it may break, you know...

and does it have two speedometers?

one of them may be lying to you and you wouldn't know it

in fact, don't trust the speedometer. count the seconds it takes for
telephone poles to pass by, and then use the formula to determine
your true speed.

it's just unsafe to blindly follow that speedometer. it's a dumb instrument.
you need to know the math.

 

[The Chairman]

Pssst... you know those Ferraris don't need no steenkin' computers!

I wonder if they realise that them thar brakes are controlled by a computer? So is the engine and the climate control. Better turn all them things off and push the mother so you stay safe! Bwahahahaha!

 

[Swan1172]

obviously they have legal departments that make them put all sorts of disclaimers
on their products in case some idiot sues.

do you really expect someone to swallow those little fluffy things they sell for
padding? why put a label on them that says "do not swallow?"

legal departments, baby

now, back to whether diving nitrox with only a computer is safe or not.

basically your argument is "computers are not perfect; some break."

same goes for watches and depth gauges. if you are following tables, you still
need a watch and a depth gauge, and they can break or run out of
batteries, just like a computer can.

that means, using your logic, that diving tables is not safe.

You can choose to call it legal manuevering, but I choose to call it common sense.

Anything mechanical has a chance of breaking, which is why it is prudent to have some kind of a back-up. Its a concept called redundancy, and it refers to the duplication of critical components of a system with the intention of increasing reliability of the system as a whole. Your argument is specious at best, as computers, watches and depth gauges rarely fail independently, so the probability of all three failing at the same time is statistically insignificant.

 

[Swan1172]

my back-up plan is simple: in case of computer failure, terminate dive inmmediatly
and ascend slowly.


end of story. and safe.

You forgot the part about possibly getting bent, because you have no idea how deep you are or how long you've been down. If you are using an air-integrated computer, you also have no idea how much gas you have left, because you totally trust your computer which would most likely mean that you don't have a redundant SPG.

Good luck and have your DAN card ready.

 

[minnesota01r6]

You forgot the part about possibly getting bent, because you have no idea how deep you are or how long you've been down. If you are using an air-integrated computer, you also have no idea how much gas you have left, because you totally trust your computer which would most likely mean that you don't have a redundant SPG.

Good luck and have your DAN card ready.

Here we go again with changing the scope of the argument because you cannot support your initial argument.

if your AI computer breaks the same thing happens as if your SPG breaks, only I would argue it can be easier to tell that your AI computer broke because it would likely display something clearly erroneous (or not display anything at all) while a SPG could "stick" at a given pressure thereby making you believe you have more air than you really do.

If you have no idea how deep you are or how long you have been down, you have not: a) been diving with a buddy, b) been monitoring your depth and time AT ALL, and c) been following safe practices for diving with a computer or with tables.