Suunto D9: Remaining Air Time and No Deco Time - WHY??

[FabioA]

Hi,

I would like to get an air integrated computer and I am interested in the Suunto D9. I just have one question: Is there any good reason for displaying the remaining air time and the No decompression time at the same time? I find this a bit confusing, as it gives two different times simultaneously. Isn´t that dangerous somehow? A diver can risk to run out of air, before running out of No Deco Time.

I am new to diving with computers and would like to know if somebody knows why it is important to show both times (remaining air time and no deco time)?

Thanks for your help,

FabioA

[ScubaMilo]

The short answer is that a diver could become low on air before they run into deco
or they may come to their NDL before they run out of air.
The two times running at the same time lets the diver plan the appropriate response.
Hope this helps.
Milo

[cpalerm]

ScubaMilo is correct in that it lets the diver make decisions.
While NDL are based on the computer's algorithm and current depth, air remaining time is affected by other things you can control (besides depth). For example, exertion is one of these factors; if you make it a point to relax and swim at a slower pace your air consumption rate will fall, and thus your air time remaing will change accordingly.

Cesar

[Hoosier]

In addition, D9 has three gas switch function. So, depending on your dive plan, you might use the separate bottle for the second air source, for example an independant double. In that case, two numbers are the essential....

[scubasimon]

Hey FabioA,

I have logged about 300 dives on the D9 and even from dive 1 it was not confusing. Both numbers are useful and very clear to distinguish from each other on the face.

The gas switch function is a very nice extra that comes in useful as I also use the D9 as my tech backup computer.

si

[melle]

Hi,

I own a Vytec, which is also air integrated. I don't find it confusing. It would be more confusing if it would only one time that was displayed: imagine, it would need to switch to the time left that is smallest... so which one is it displaying. Now you know.

Besides that. You need to know your computer and what it can display (especially the special situations... deco, fast descents, mandatory/proposed stops, etc.) very thoroughly anyway, *before* you dive with it. So... you get used to that very easily.
Read the manual 1000 times, fiddle around with all the controls, and displays, until you're familiar with them. It will not be a problem.

Greetings,

Melle