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
JO 539
U.S. Official No. 518819
Not yet on Master's MateType
Freight Barge
Flag
USALength
42.7 m
Beam
11.9 m
Draft
2.6 m
First reported
Jun 2026
AIS reports
1
JO 539 flies the American flag — a 42.7-metre barge. Below, she has 11.9 metres in the beam and a draft measuring 2.6 metres. On the registers she's U.S. official number 518819. Big or small, every hull benefits from the free Master's Mate Safety Initiative Network — JO 539 included.
Free forever · No credit card · for commercial operators
Eyes on JO 539, 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 JO 539 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 JO 539 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 JO 539 and switch it all on
Free to join · nothing to install to start · cancel anytime
About JO 539
What kind of vessel is JO 539?
JO 539 is a Freight Barge flagged to United States of America.
What is JO 539's U.S. Official No.?
JO 539's U.S. Official No. is 518819.
How big is JO 539?
JO 539 is about 42.7 m long, 11.9 m on the beam, drawing 2.6 m.
Is JO 539 on the Master's Mate Safety Initiative Network?
Not yet. If JO 539 is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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