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.
Industrial Vessel
BIG JOHN
U.S. Official No. 507464
Not yet on Master's MateType
Industrial Vessel
Flag
USALength
54.9 m
Beam
21.4 m
Draft
3.4 m
First reported
Jun 2026
AIS reports
1
Out of the United States, BIG JOHN is a 54.9-metre commercial vessel. She carries a beam measuring 21.4 metres and a 3.4 m draft. Look for U.S. official number 507464. BIG JOHN belongs on the Master's Mate Safety Initiative Network, a free safety net shared by boats the world over.
Free forever · No credit card · for commercial operators
Eyes on BIG JOHN, 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 BIG JOHN 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 BIG JOHN 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 BIG JOHN and switch it all on
Free to join · nothing to install to start · cancel anytime
About BIG JOHN
What kind of vessel is BIG JOHN?
BIG JOHN is a Industrial Vessel flagged to United States of America.
What is BIG JOHN's U.S. Official No.?
BIG JOHN's U.S. Official No. is 507464.
How big is BIG JOHN?
BIG JOHN is about 54.9 m long, 21.4 m on the beam, drawing 3.4 m.
Is BIG JOHN on the Master's Mate Safety Initiative Network?
Not yet. If BIG JOHN is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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