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.
Passenger (Inspected)
John W. Johnson
MMSI 367452810 · Call sign WDF4516
Not yet on Master's MateType
Passenger (Inspected)
Flag
USALength
80.4 m
Beam
19.9 m
Draft
4.7 m
Call sign
WDF4516
IMO
9602344
Official No.
1228845
AIS reports
3
On the American registry, John W. Johnson is an 80.4-metre ferry vessel. Her hull carries 19.9 metres in the beam and a draft of 4.7 m. Officially she's MMSI 367452810, call sign WDF4516, IMO 9602344. Claim John W. Johnson free on the Master's Mate Safety Initiative Network and let nearby cruisers have her back.
Free forever · No credit card · for passenger & charter operators
Keep every soul aboard John W. Johnson safe.
Distress alerting, live AIS, onboard monitoring and weather routing — the safety stack for boats that carry people.
Switch on the safety stack — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Wherever John W. Johnson 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 passenger & charter operators
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put John W. Johnson on the map. It hands you the full bridge:
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
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.
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.
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 John W. Johnson and switch it all on
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About John W. Johnson
What kind of vessel is John W. Johnson?
John W. Johnson is a Passenger (Inspected) flagged to United States of America.
What is John W. Johnson's MMSI?
John W. Johnson's MMSI is 367452810. Call sign WDF4516. IMO 9602344.
How big is John W. Johnson?
John W. Johnson is about 80.4 m long, 19.9 m on the beam, drawing 4.7 m.
Is John W. Johnson on the Master's Mate Safety Initiative Network?
Not yet. If John W. Johnson is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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