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
SONOMA
MMSI 366969970 · Call sign WZC8517
Not yet on Master's MateType
Passenger
Flag
USALength
47 m
Beam
10 m
Draft
2 m
Call sign
WZC8517
Official No.
578765
First reported
Jun 2026
Last reported
Jun 2026
AIS reports
72
SONOMA, a ferry under American registration, measures 47 metres on deck. She's built with a beam measuring 10 metres and a 2-metre draft. On the registers she's MMSI 366969970, call sign WZC8517. Claim SONOMA 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 SONOMA 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
Live AIS position · Jun 9, 2026 03:20 UTC
Position
37.9281° N, 122.4688° W
Status
Under way (sailing)
Speed
11.5 kn
Course
296°
Destination
XX XXX>US^0VC6
Sailing San Francisco Bay? You're never out there alone.
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Joining the Safety Initiative Network doesn't just put SONOMA 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 SONOMA and switch it all on
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About SONOMA
What kind of vessel is SONOMA?
SONOMA is a Passenger flagged to United States of America.
Where was SONOMA last seen?
SONOMA was last reported in San Francisco Bay in Jun 2026 on public AIS.
What is SONOMA's MMSI?
SONOMA's MMSI is 366969970. Call sign WZC8517.
How big is SONOMA?
SONOMA is about 47 m long, 10 m on the beam, drawing 2 m.
Is SONOMA on the Master's Mate Safety Initiative Network?
Not yet. If SONOMA is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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