Dive Table vs. "The Wheel"

[vancehobart]

Without getting into the politics of NAUI vs. PADI, which is would be better all-round to plan a dive with? NAUI's Dive Tables or PADI's "THE WHEEL"?
I just became certified as a Recreational diver with NAUI. I bought a dry suit on line because I dive in N. Cal waters. A PADI Recreational Dive Planner, Instruction booklet, study guide and "THE WHEEL" came with the dry suit.
After briefly reading "THE WHEEL'S" instruction book it appears more precise in planning a dive.
All your comments, advice, etc. would be greatly appreciated!
Thanks,
Vance "n" Vacaville

 

[Charlie99]

You have two comparasions going on at the same time. 1) The base tables are different between PADI and NAUI, and 2) the wheel is a MULTI-LEVEL calculator, while the tables (when used in the standard approved fashion) calculate the dives as if it was all at the deepest depth ("square profile").

The Naui tables (pre-RGBM version) are based on the Navy/Workmann tables, and track a single 2 hour compartment. The PADI tables are based on the DSAT test data and track just the 1 hour compartment, with some special "X,Y,Z" rules to take care of the only no-deco dives where compartments slower than 60 minutes matter (long, shallow dives).

The result of the differences between the table construction is that PADI tables are much more liberal in repetitive dive situations --- not because they are truly more liberal, but because they are a better correlation with reality.

If you are doing a multilevel dive, the wheel does a much better job of calculating your true N2 loading, and will allow significantly more bottom time.

Charlie

 

[jlyle]

Buy a computer, dude! I don't know of any long-time divers who use tables/wheel. The tables are okay for square profile dives and the wheel is more appropriate for multilevel dives, but you will want to buy a computer if you are going to be doing a lot of diving as it will give you maximum credit for time spent at shallower levels and extend your bottom time. Isn't bottom time what it's all about?

DSAO

 

[JDostal]

I know quite a few long time divers that use tables But that's a matter of preference.

You can actually use straight tables to calculate multi-level dives as well - if you compare the wheel to working out the dive on a padi rdp, they are almost the same. The wheel just presents the data in an easier format.

The wheel is definitely nicer for multi-level dives.

 

[Al Mialkovsky]

People still dive without computers?

 

[Mako Mark]

You can actually use straight tables to calculate multi-level dives as well -

This is called "helter skelter diving" and has only been tested anecdotally by idiots like me that didnt know better in the days before they published and tested the wheel for Multi Level diving

they are almost the same.

so you "almost" wont get bent?

The wheel is simple and accurate and is tested on recreational divers like us, it is a good tool.

Get a computer and know how to back it up with a set of tables in the unlikely case that it fails.

 

[Charlie99]

[using straight tables to calculate multilevel dives].. is called "helter skelter diving" and has only been tested anecdotally by idiots like me that didnt know better in the days before they published and tested the wheel for Multi Level diving.

Mark, if you look a little bit more closely, you will see that the wheel is simply the PADI RDP physically morphed a bit. Same pressure groups. Same time entries in the table. The wheel just adds 5' depth increments, "ML's", and rules on depth changes.

It is pretty easy to use the PADI RDP in a way that you get the same calculation results as with the wheel. The only addition you need to make to the tables to have them give the same results as the wheel is the "ML" or "multilevel NDLs". You must also, of course, follow the other restrictions of the wheel such as the maximum depth for 2nd and 3rd levels.

If you are still not convinced, then play around a bit with a table I uploaded to the photo gallery (300kb GIF file, too big to attach):
http://www.scubaboard.com/gallery/showphoto.php/photo/3142

Charlie

 

[ShakaZulu]

How do you guys plan a week long dive trip without a RDP????

 

[V-Erthal]

You have two comparasions going on at the same time. 1) The base tables are different between PADI and NAUI, and 2) the wheel is a MULTI-LEVEL calculator, while the tables (when used in the standard approved fashion) calculate the dives as if it was all at the deepest depth ("square profile").

The weel is a more complete way to calculate a dive than the tables, since it can not only calculate mililevel dives but calculate square dives and repetitive dives giving you the adjusted bottom time.

Yes, the computers are very, very usefull, but you have to know math before you use a calculator. In the event of a failure you have to know the pinciples of diving, and knowing how to use a dive table/weel will do no harm.

 

[adder70]

People still dive without computers?

eepwalla Waiting for the DIR folks to see this.