USER GUIDE

Prepare GMDSS work

Choose distress, urgency or safety, complete the DSC worksheet, run readiness checks and create authorized log records. Use MSI/NAVTEX and station information as decision support only; transmit using certified equipment and approved procedures.

How to interpret it safely

The user guide explains what the information means, how the result is produced and which warnings or limits matter.

Follow the steps in the app

See the main screens

Practical learning and web tools

What to know before you use it

How to use this feature well

Use worksheets and readiness records as preparation aids: confirm sea area, equipment, source revision and transmission responsibility against the ship's approved radio procedures.

Where the information comes from

Prepare GMDSS work: Before using a result, check its provider, datum, time basis, confidence and installed-data details.

Check your inputs

Prepare GMDSS work: Complete missing information and correct inconsistent or out-of-range vessel, position and calculation values.

Understand the calculation

Prepare GMDSS work: Keep the units, vessel particulars, time zone and selected method in view when reading a result or export.

When to stop and review

Prepare GMDSS work: Read each warning, correct its cause and recalculate before continuing.

Use it within its limits

Prepare GMDSS work: CaptainCalc supports decisions; approved vessel documents, official publications and the master's judgement remain authoritative.

Continue learning

CaptainCalc is decision support. It never replaces approved stability data, loading computers, ECDIS, official publications, procedures or professional judgment.

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