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.
Tug
RB-401
MMSI 273543820 · Call sign RB-401
Not yet on Master's MateType
Tug
Flag
RUSLength
25 m
Beam
9 m
Draft
3.5 m
Call sign
RB-401
First reported
Jun 2026
Last reported
Jun 2026
AIS reports
3
A Russian harbour tug, RB-401 measures 25 metres. Below, she has a 9 m beam and a draft of 3.5 m. She's listed under MMSI 273543820, call sign RB-401. RB-401 is invited to the free Master's Mate Safety Initiative Network, where cruisers keep each other safe.
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Built for boats that work — like RB-401.
Engine & systems telemetry, live AIS, weather and distress alerting for the vessels that earn their keep.
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Last known position · Jun 2, 2026
Position
54.6361° N, 19.9097° E
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Joining the Safety Initiative Network doesn't just put RB-401 on the map. It hands you the full bridge:
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
Live AIS & Traffic
See every vessel around you in real time. Closest-approach warnings before they matter.
Weather & Routing
GRIB wind, swell & current on the chart. Plan passages with ETA-calibrated forecasts per leg.
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
Anchor Watch
GPS-precise drag alarms that actually wake you — and your whole crew. Sleep through the night.
Worldwide Charts
Navionics-grade vector charts, satellite & raster overlays, online or off. Your whole cruising ground.
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 RB-401 and switch it all on
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About RB-401
What kind of vessel is RB-401?
RB-401 is a Tug flagged to Russia.
Where was RB-401 last seen?
RB-401 was last reported in the Baltic Sea in Jun 2026 on public AIS.
What is RB-401's MMSI?
RB-401's MMSI is 273543820. Call sign RB-401.
How big is RB-401?
RB-401 is about 25 m long, 9 m on the beam, drawing 3.5 m.
Is RB-401 on the Master's Mate Safety Initiative Network?
Not yet. If RB-401 is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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