Quiz - Recreational Dive Planner™ - Max Time

[Scraps]

Noone would use different computers (or remove the battery to reset) on each dive, would they?

Nah, you only switch computers or change batteries if your primary computer locks you out for the rest of the day and you want to keep diving, right?

 

[tursiops]

The problem is that very few people use tables for their diving, and those table computations in your log book are no longer necessary. Divers using computers on multi-level dives have struggled with how to deal with bottom time. Consequently, PADI has told them that for computer-based dives, they can pretty much do what they want, including surface to surface (which is what I do).

The underlying thing is how BT is even used.
Back when one used tables and wristwatches, BT was what you tracked because you needed to know when to ascend to the surface, and you also logged that number.
Today, you often don't even know your bottom-time/time-at-depth, but rather your computer tells you how much time is left until you hit your NFL/no-stop limit. When you get to the surface, your computer tells you "dive time," which will invariably be longer than your BT, even for a square profile, because it includes ascent time (and maybe safety stop time too). So you log "dive time" and don't even need the old concept of a BT.
That's what PADI means....

 

[Storker]

Your bottom time ends when you begin your direct ascent toward the surface (which may include a safety stop). There are no variations.

Which is why tables are rather misleading if I use them on one of my typical dives. I hardly ever dive a square profile; almost every dive I do has a more or less triangular profile. Those dives can be (very) roughly approximated by a multilevel profile, but hardly ever with a typical table dive.

 

[scubadada]

So.... @Pedro Burrito quizzes are still prompting some good discussion on SB. Thanks

 

[boulderjohn]

Which is why tables are rather misleading if I use them on one of my typical dives. I hardly ever dive a square profile; almost every dive I do has a more or less triangular profile. Those dives can be (very) roughly approximated by a multilevel profile, but hardly ever with a typical table dive.

And that is why the overwhelming majority of divers today use computers.

My first post certification dives were more than 20 years ago, and it was in Cozumel, where all dives must be led by a DM, and all those dives are multi-level. After the first such dive, I whipped out my tables while sitting on the boat during the surface interval and saw that my dive was far, far off those tables. I was puzzled. How could I plan for the next dive? I looked up and saw that all my fellow divers were looking at me in amusement. One of them said, "It makes a decent frisbee."

I bought my first computer as soon as I got home.

That is still the only time I ever saw anyone attempt to use tables on a dive outside of a class.

 

[rhwestfall]

Wrecks in the Great Lakes still are square...

 

[Storker]

That is still the only time I ever saw anyone attempt to use tables on a dive outside of a class.

Well, I still find them useful for rough planning and reality-checking what my computer tells me. Particularly since I learned how to approximate a multilevel dive with the standard PADI RDP.

For me, it isn't either-or. It's both.

 

[boulderjohn]

Well, I still find them useful for rough planning and reality-checking what my computer tells me. Particularly since I learned how to approximate a multilevel dive with the standard PADI RDP.

For me, it isn't either-or. It's both.

You computer doesn't have a planning function?

 

[Storker]

You computer doesn't have a planning function?

I just hate punching the buttons and waiting for the response. It takes ages. For NDL dives, I find it easier and much faster to use the tables and the multilevel approximation for planning.

My opinion only.

 

[Pedro Burrito]

Spoiler: Answer

b. Metric 19 minutes - Imperial 24 minutes