Marine Glossary
MMSI
Maritime Mobile Service Identity. A unique 9-digit number that identifies your vessel for DSC calls. Free from BoatUS (U.S.) or FCC (international).
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Articles mentioning “MMSI”
Guides6mWinterizing Your Boat: The Complete Off-Season Checklist
Proper winterization prevents $5,000+ in freeze damage. Learn the 12-step process from engine fogging to antifreeze that keeps your boat safe all winter.
Captain Sarah Okonkwoupd
Guides7mSail Trim Basics: More Speed and Balance
Sail trim is the art of adjusting sails for the wind. Learn to read telltales, understand the slot effect, and trim for pointing vs reaching in this guide.
Captain Marcus Reedupd
Guides6mMarine Electrical Systems: Safe Power On The Water
Your boat's electrical system is the difference between a great day and a tow home. Learn 12V DC basics, battery management, and the 5 most common failures.
Captain Sarah Okonkwoupd
Guides9mDocking in Wind: 5 Techniques Every Boater Needs
Docking is the #1 source of boating anxiety. Learn 5 techniques: spring lines, warping, pivoting, ferry angle, and the emergency kamikaze abort.
Captain Marcus Reedupd