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
SBI NO. 521
U.S. Official No. 277613
Not yet on Master's MateType
Freight Barge
Flag
USALength
59.4 m
Beam
10.7 m
Draft
3.1 m
First reported
Jun 2026
AIS reports
1
SBI NO. 521 is a barge sailing under the American flag, 59.4 metres overall. She carries a 10.7-metre beam and a 3.1-metre draft. She's listed under U.S. official number 277613. The Master's Mate Safety Initiative Network welcomes SBI NO. 521 — free to join, cruiser-run, and always on watch.
Free forever · No credit card · for commercial operators
Eyes on SBI NO. 521, 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 SBI NO. 521 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 SBI NO. 521 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 SBI NO. 521 and switch it all on
Free to join · nothing to install to start · cancel anytime
About SBI NO. 521
What kind of vessel is SBI NO. 521?
SBI NO. 521 is a Freight Barge flagged to United States of America.
What is SBI NO. 521's U.S. Official No.?
SBI NO. 521's U.S. Official No. is 277613.
How big is SBI NO. 521?
SBI NO. 521 is about 59.4 m long, 10.7 m on the beam, drawing 3.1 m.
Is SBI NO. 521 on the Master's Mate Safety Initiative Network?
Not yet. If SBI NO. 521 is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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