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)
Harbor Seal
MMSI 366862410 · Call sign WDA9187
Not yet on Master's MateType
Passenger (Inspected)
Flag
USALength
11.9 m
Beam
2.6 m
Draft
1.5 m
Call sign
WDA9187
Official No.
1128945
AIS reports
1
Harbor Seal is an American 11.9-metre passenger craft. Below, she has a 2.6-metre beam and a draft measuring 1.5 metres. Look for MMSI 366862410, call sign WDA9187. Harbor Seal carries passengers; the free Master's Mate Safety Initiative Network helps carry the watch, with distress alerting and a network nearby.
Free forever · No credit card · for passenger & charter operators
Keep every soul aboard Harbor Seal 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 Harbor Seal 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 Harbor Seal 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 Harbor Seal and switch it all on
Free to join · nothing to install to start · cancel anytime
About Harbor Seal
What kind of vessel is Harbor Seal?
Harbor Seal is a Passenger (Inspected) flagged to United States of America.
What is Harbor Seal's MMSI?
Harbor Seal's MMSI is 366862410. Call sign WDA9187.
How big is Harbor Seal?
Harbor Seal is about 11.9 m long, 2.6 m on the beam, drawing 1.5 m.
Is Harbor Seal on the Master's Mate Safety Initiative Network?
Not yet. If Harbor Seal is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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