Version 15 (modified by eskil, 15 years ago)

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Baltic Deco Planner Frequently Asked Question

Have a question ?
Want more details to an existing answer ?
Feel free to post a question in the Q&A Forum.

Feedback

I'd like to report a problem, how and where ?

You're welcome to file a ticket (you can now do this without registering first), post in the Q&A forum (requires registration) or via  email. If the report is related to a generated dive plan, please be sure to include the plan parameters and if possible, the plan itself. You can use the apps email feature to email the plan to yourself.

I'd like to suggest a feature/enhancement, how and where ?

Please post these in the REEFS forum first. This will give me some time to think about it and let other people chime in. If the feature isn't already on the roadmap, a ticket can be filed to keep it on the map.

I have some concerns/comments…

Again, feel free to reach out directly to  me or post about them in the Q&A forum.

How do I ... ?

Plan a CCR bailout ?

Make a plan, and add some bailout gases and make sure to mark them as BAIL. Both gases marked as BAIL and OC are used for bailout (OC ones are also used for doing OC deco). Once you have any levels with a CCR setpoint, deco gases can be marked as BAIL, and this means that this gas is only to be used when doing bailout calculation.

Now tap any level/decostop, and a action sheet will pop-up offering to show a bailout from this spot.

CCR Bailout and repetitive dives, how do I ... ?

If you've done a CCR bailout and you want to know what happens to the rest of the dives (assuming you're not calling it quits for the day), you'll have to change the plan, in which you bailed, or the repetitive dives will be calculated wrong. Since Baltic supports bailout planning for both levels and stops, it's fairly simple to capture this for repetitive dives by modifying levels and gases.

Say that you bailed at the 70fsw/21msw stop, go to your plan and change your bailout gasses (that would cover the 70fsw/21msw stop) from BAIL to OC and set the start depth accordingly if necessary. The plan will now reflect the bailout, and subsequent dives in the workset will take this into account.

Algorithms

What tables/algorithm does Baltic use ?

Baltic implements VPM/B and ZHL16B with Gradient Factors, it is not based on table look-ups.

What ZHL16 values are used ?

The halftimes used (0.9 and upwards) are ;

  • N2: 4, 8, 12.5, 18.5, 27, 38.3, 54.3, 77, 109, 146, 187, 239, 305, 390, 498, 635
  • He: 1.88, 3.02, 4.72, 6.99, 10.21, 14.48, 20.53, 29.11, 41.20, 55.19, 70.69, 90.34, 115.29, 147.42, 188.24, 240.03

For ZHL16, the a and b coeffecients are the B table values. Prior to the public 0.9 release, the 1b N2 halftime of 5 minutes was used.

Where did the algorithm implementations come from ?

Both were implemented for another project in 2007 and 2008 respectively. The ZHL16 implementation is based on available litterature, such as Dr. Bühlmann's Tauchmedizin, Dr. Wienke's Technical Diving in Depth and Erik C. Bakers many papers on decompression calculations.

The VPM/B implementation is a reimplementation (no, not a f2c generated conversion) of Erik C. Baker's reference fortran implementation.