Multi Level Diving?

[oceancrest67]

As they say...plan your dive and dive your plan.

Now with dive computers...multi-level diving is easier in the sense that many computers track air consumption, nitrogen loading, time spent, residual time and other variables at given depths at the same time using complex algorithims.

Yes, one can plan a multi level dive using the tables and/or using the wheel...but this takes some calculation and tracking with tables and slate in hand etc.

Simply put...dive computers do the work for the diver. Most experienced recreational divers multi level their dives anyway...hitting the deepest depth first and then multi leveling to shallower depths as the dive progresses...the last level being the safety stop.

Relying fully on a dive computer can lead to a false sense of security...fully integrated dive computers can have several points of failure...battery failure etc.

I use a fully integrated computer...the last dive i did was up at altitude in a lake...when I downloaded the dive information and checked the dive profile, it was in a classic staged multi level profile.

Just some FYI.

 

[Dragon2115]

Here's the difference between the different methods.

RDP Table - plans only rectangular dive profiles using max depth. Can be used on-the-fly during the dive but can be difficult. Most just use them to plan the dive and then stick to that plan. In a typical profile that starts out at its deepest point and then gets shallower this adds a margin of conservativeness that some find desireable.

The Wheel - Plans rectangular dive profiles but can also plan multi-level dive profiles. Can be used on-the-fly but but again, difficult to read underwater. Note: When planning a multi-level dive using the wheel you must ascend above a certain threshold, depending on your original depth, before you get any credit for going shallower.

Computers - Most computers I've seen don't provide for advanced multi-level planning. However what they do is keep track of on-gassing and off-gassing using on-the-fly calculations. What that means is that if you ascend or descend, even if only a few feet, the computer tracks this and recalculates your NDL based on the new data. Where a large number of dives start out at their deepest point and then work their way up during the dive a computer can substantially lengthen the NDL by using this on-the-fly calculation method.

 

[Uncle Pug]

I'm biting my tongue.

But in a few hours I'll go out and do two multilevel dives to 100'+ spending 3+ hours under water without a computer.

I'll post a picture.

 

[boomx5]

I'm biting my tongue.

But in a few hours I'll go out and do two multilevel dives to 100'+ spending 3+ hours under water without a computer.

I'll post a picture.

Knowing you, you'll probably be using a single AL80 for the dive also.