Master's MateSafety Initiative Network
The Master's Mate Safety Initiative Network (MMSIn) — like AAA for the ocean, but free & community-driven. Cruisers keeping each other safe: anchor-drag & distress alerts, a verified captains directory, and a watch network that has your back.
Freight Barge
C 121B
U.S. Official No. 547709
Not yet on Master's MateType
Freight Barge
Flag
USALength
61 m
Beam
10.7 m
Draft
3.3 m
First reported
Jun 2026
AIS reports
1
C 121B, a barge registered in the United States, measures 61 metres on deck. Below, she has a beam of 10.7 m and a draft measuring 3.3 metres. On the registers she's U.S. official number 547709. Join C 121B to the Master's Mate Safety Initiative Network — free, and built by cruisers for cruisers.
Free forever · No credit card · for commercial operators
Eyes on C 121B, around the clock.
Real-time AIS, full systems telemetry, distress alerting and worldwide charts — your hull on one dashboard, from anywhere.
Put her on the dashboard — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Wherever C 121B roams, you're never out there alone.
Thousands of cruisers on the Master's Mate Network — ready to help the moment something goes wrong.
Free with your claim · for commercial operators
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put C 121B on the map. It hands you the full bridge:
Live AIS & Traffic
See every vessel around you in real time. Closest-approach warnings before they matter.
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
Worldwide Charts
Navionics-grade vector charts, satellite & raster overlays, online or off. Your whole cruising ground.
Weather & Routing
GRIB wind, swell & current on the chart. Plan passages with ETA-calibrated forecasts per leg.
Anchor Watch
GPS-precise drag alarms that actually wake you — and your whole crew. Sleep through the night.
Onboard Cameras
Watch your boat from anywhere — live feeds and 24h recording, straight from your gateway.
Hail Any Captain
A verified captains directory + direct hailing. Reach the boat next to you, or across the bay.
Claim C 121B and switch it all on
Free to join · nothing to install to start · cancel anytime
About C 121B
What kind of vessel is C 121B?
C 121B is a Freight Barge flagged to United States of America.
What is C 121B's U.S. Official No.?
C 121B's U.S. Official No. is 547709.
How big is C 121B?
C 121B is about 61 m long, 10.7 m on the beam, drawing 3.3 m.
Is C 121B on the Master's Mate Safety Initiative Network?
Not yet. If C 121B is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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