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
British Tranquillity
MMSI 257358000
Not yet on Master's MateFlag
NORLength
183 m
IMO
9288849
AIS reports
1
British Tranquillity is a boat under Norwegian registration, 183 metres long. She broadcasts as MMSI 257358000, IMO 9288849. British Tranquillity is welcome on the Master's Mate Safety Initiative Network — a free, community-run watch where boats look out for one another.
Free forever · No credit card
Is British Tranquillity 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
Wherever British Tranquillity 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
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put British Tranquillity 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 British Tranquillity and switch it all on
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About British Tranquillity
What kind of vessel is British Tranquillity?
British Tranquillity is a vessel flagged to Norway.
What is British Tranquillity's MMSI?
British Tranquillity's MMSI is 257358000. IMO 9288849.
How big is British Tranquillity?
British Tranquillity is about 183 m long.
Is British Tranquillity on the Master's Mate Safety Initiative Network?
Not yet. If British Tranquillity is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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