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
51 HJ
MMSI 440188520 · Call sign 775548
Not yet on Master's MateType
Tug
Flag
KORLength
12 m
Beam
6 m
Draft
2 m
Call sign
775548
First reported
Jun 2026
Last reported
Jun 2026
AIS reports
40
Out of South Korea, 51 HJ is a 12-metre working tug. She carries a beam measuring 6 metres and a 2-metre draft. On the registers she's MMSI 440188520, call sign 775548. It's free to add 51 HJ to the Master's Mate Safety Initiative Network — like AAA for the ocean, run by the cruisers who use it.
Free forever · No credit card · for working boats
Built for boats that work — like 51 HJ.
Engine & systems telemetry, live AIS, weather and distress alerting for the vessels that earn their keep.
Rig her out — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Last known position · Jun 3, 2026
Position
34.9384° N, 128.9288° E
Working the Sea of Japan? You're never out there alone.
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Joining the Safety Initiative Network doesn't just put 51 HJ 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 51 HJ and switch it all on
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About 51 HJ
What kind of vessel is 51 HJ?
51 HJ is a Tug flagged to South Korea.
Where was 51 HJ last seen?
51 HJ was last reported in the Sea of Japan in Jun 2026 on public AIS.
What is 51 HJ's MMSI?
51 HJ's MMSI is 440188520. Call sign 775548.
How big is 51 HJ?
51 HJ is about 12 m long, 6 m on the beam, drawing 2 m.
Is 51 HJ on the Master's Mate Safety Initiative Network?
Not yet. If 51 HJ is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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