A few Table Use Questions

[navy85]

SubMariner once bubbled...
I’d argue in favour of keeping the statement in context, which was:

"...but I wouldn't advocate using the "Flat" PADI Recreational Dive Planner at all for multi-level diving.
The PADI Wheel is the best way to calculate multi-level profiles and is much easier to use.”

I was comparing two versions of the RDP not the RDP vs a dive computer.

I have read this thread with interest, especially when I saw comments such as the YMCA prohibits multilevel table use and SSI does not advocate or teach it. The dive logs that came with my PADI OW pak have a planner for multi-level diving. I recall being taught a method to use in OW was to assume a zero SI with the flat RDP that came with my materials. I reviewed them this evening to find that "the Wheel version of the RDP can be used for multilevel diving". So I learned something extremely important (not that my dives approach the NDL).

That being said, PADI has a Multilevel Dive specialty (which uses the Wheel RDP or a computer). Do the other agencies teach this or similar? I didn't see anything like it for SSI. Do the earlier postings WRT YMCA and SSI mean that this subject is ignored, or do they advocate the use of a dive computer? The reality for the limited diving I have done is that in certain areas - such as reefs - your dive profile will be multi-level, so it seems strange that it is not taught.

 

[SubMariner]

The dive logs that came with my PADI OW pak have a planner for multi-level diving. I recall being taught a method to use in OW was to assume a zero SI with the flat RDP that came with my materials. I reviewed them this evening to find that "the Wheel version of the RDP can be used for multilevel diving".

Addressing each point:

1) Most PADI crewpacks come with the divelog that has a myriad of Specialties/Dives in it beyond basic Open Water. This includes Multi-level diving, which has a significantly different graphic representation than the classic "square" dive profile. Multi-level diving is NOT part of the OW course.

2) PADI does NOT advocate teaching a multi-level profile using the "flat" RDP. Personally, I know of no Instructor who teaches the method you describe. We do, however, teach multi-level diving using The Wheel version of the RDP.

3) The Wheel version of the RDP can be used to plan either square OR multi-level profiles. The only reason the majority of crew packs come with the "flat" RDP is cost: most people don't want to pay more money for the Wheel. If you go back through your OW student manual you will probably see that there is a reference to diving with the Wheel. However, because you had the other RDP, that's what your Instructor taught you to use.

Now back to your regularly scheduled program, already in progress...

~SubMariner~

 

[Doof]

Any reason why using the "flat" RDP to plan multi-level dives is so frowned upon? Are there situations where the RDP and the Wheel would disagree?

 

[navy85]

SubMariner once bubbled...


Addressing each point:

1) Most PADI crewpacks come with the divelog that has a myriad of Specialties/Dives in it beyond basic Open Water. This includes Multi-level diving, which has a significantly different graphic representation than the classic "square" dive profile. Multi-level diving is NOT part of the OW course.

2) PADI does NOT advocate teaching a multi-level profile using the "flat" RDP. Personally, I know of no Instructor who teaches the method you describe. We do, however, teach multi-level diving using The Wheel version of the RDP.

3) The Wheel version of the RDP can be used to plan either square OR multi-level profiles. The only reason the majority of crew packs come with the "flat" RDP is cost: most people don't want to pay more money for the Wheel. If you go back through your OW student manual you will probably see that there is a reference to diving with the Wheel. However, because you had the other RDP, that's what your Instructor taught you to use.

Thanks for the info. I didn't mean to imply that I did multi-level diving in my OW course - just asking if the YMCA or SSI had advanced courses that covered multi-level diving similar to PADI. Some statements by others in this thread left me with the impression that these two organizations didn't teach it at all, and I was trying to confirm whether my interpretation of those comments was correct.

I recall using the flat RDP to do a few short class exercises constructing a multi-level dive profile. I do not recall being given a choice of whether I wanted the course materials with the Wheel or flat RDP. And yes, when I looked back through my materials last night, every reference to multi-level diving (both of them) specifically stated that the Wheel version should be used.

I actually started an OW course 20 years ago in college but was never able to complete the required dives (a new girlfriend, limited time, long story). Somewhere I still have the RDP Wheel I got in that training. It would be interesting to see how the tables have changed if at all from the early 1980s to now.

 

[SubMariner]

Any reason why using the "flat" RDP to plan multi-level dives is so frowned upon? Are there situations where the RDP and the Wheel would disagree?

It's not that it's frowned upon, it's just that the "flat" RDP simply isn't designed to be used for multi-level diving.

If you are planning square profile dives, the two versions of the RDP will agree. However, you really cannot plan a multi-level dive using the "flat" RDP.

Basically, it's like saying "a parrotfish is the same as a shark". Are they both fish? Yes. Are they the same? No.

Meanwhile, time to come back to diving, navy85. Get into a course & get to the water!

~SubMariner~

 

[Doof]

SubMariner once bubbled...
However, you really cannot plan a multi-level dive using the "flat" RDP.

Using the 0-minute surface interval method... why couldn't you?