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
IOANNIS THIRESIA
MMSI 237816200 · Call sign SY4912
Not yet on Master's MateType
Passenger
Flag
GRCLength
84 m
Beam
20 m
Draft
2 m
Call sign
SY4912
IMO
8989393
First reported
Jun 2026
Last reported
Jun 2026
AIS reports
44
IOANNIS THIRESIA is a passenger ship on the Greece registry, 84 metres on deck. Her hull carries a 20-metre beam and a draft measuring 2 metres. She broadcasts as MMSI 237816200, call sign SY4912, IMO 8989393. Bring IOANNIS THIRESIA aboard the Master's Mate Safety Initiative Network — free, and every captain on it has the others' backs.
Free forever · No credit card · for passenger & charter operators
Keep every soul aboard IOANNIS THIRESIA 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
Last known position · Jun 3, 2026
Position
37.9631° N, 23.5259° E
Sailing the Aegean Sea? 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 IOANNIS THIRESIA 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 IOANNIS THIRESIA and switch it all on
Free to join · nothing to install to start · cancel anytime
About IOANNIS THIRESIA
What kind of vessel is IOANNIS THIRESIA?
IOANNIS THIRESIA is a Passenger flagged to Greece.
Where was IOANNIS THIRESIA last seen?
IOANNIS THIRESIA was last reported in the Aegean Sea in Jun 2026 on public AIS.
What is IOANNIS THIRESIA's MMSI?
IOANNIS THIRESIA's MMSI is 237816200. Call sign SY4912. IMO 8989393.
How big is IOANNIS THIRESIA?
IOANNIS THIRESIA is about 84 m long, 20 m on the beam, drawing 2 m.
Is IOANNIS THIRESIA on the Master's Mate Safety Initiative Network?
Not yet. If IOANNIS THIRESIA is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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