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.
Vessel
CAPT JOHN & SON IV
MMSI 367747980 · Call sign WDI9372
Not yet on Master's MateFlag
USACall sign
WDI9372
Official No.
683977
First reported
Jun 2026
Last reported
Jun 2026
AIS reports
39
On the American registry, CAPT JOHN & SON IV is a craft. She broadcasts as MMSI 367747980, call sign WDI9372. Join CAPT JOHN & SON IV to the Master's Mate Safety Initiative Network — free, and built by cruisers for cruisers.
Free forever · No credit card
Is CAPT JOHN & SON IV your boat?
Your free claim unlocks the most powerful cruising platform ever built — anchor watch, worldwide charts, live AIS, weather routing, and a network of cruisers watching each other’s backs.
Claim this boat — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Last known position · Jun 3, 2026
Position
41.9755° N, 70.6528° W
Crossing off the U.S. East Coast? 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
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put CAPT JOHN & SON IV on the map. It hands you the full bridge:
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.
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.
Onboard Cameras
Watch your boat from anywhere — live feeds and 24h recording, straight from your gateway.
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.
Hail Any Captain
A verified captains directory + direct hailing. Reach the boat next to you, or across the bay.
Claim CAPT JOHN & SON IV and switch it all on
Free to join · nothing to install to start · cancel anytime
About CAPT JOHN & SON IV
What kind of vessel is CAPT JOHN & SON IV?
CAPT JOHN & SON IV is a vessel flagged to United States of America.
Where was CAPT JOHN & SON IV last seen?
CAPT JOHN & SON IV was last reported in off the U.S. East Coast in Jun 2026 on public AIS.
What is CAPT JOHN & SON IV's MMSI?
CAPT JOHN & SON IV's MMSI is 367747980. Call sign WDI9372.
Is CAPT JOHN & SON IV on the Master's Mate Safety Initiative Network?
Not yet. If CAPT JOHN & SON IV is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
© 2026 Master’s Mate. All rights reserved.