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.
Offshore Supply Vessel
HOS Explorer
MMSI 366899420 · Call sign WDB4530
Not yet on Master's MateType
Offshore Supply Vessel
Flag
USALength
63 m
Beam
14 m
Draft
4.9 m
Call sign
WDB4530
IMO
8964410
Official No.
1076230
AIS reports
1
HOS Explorer is a harbour workboat wearing American colours, 63 metres long. She has a 14-metre beam and a draft of 4.9 m. On the registers she's MMSI 366899420, call sign WDB4530, IMO 8964410. HOS Explorer can join the Master's Mate Safety Initiative Network for free: think of it as a watch network that has every boat's back.
Free forever · No credit card · for working boats
Built for boats that work — like HOS Explorer.
Engine & systems telemetry, live AIS, weather and distress alerting for the vessels that earn their keep.
Rig her out — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Wherever HOS Explorer 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 working boats
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put HOS Explorer on the map. It hands you the full bridge:
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
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.
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
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 HOS Explorer and switch it all on
Free to join · nothing to install to start · cancel anytime
About HOS Explorer
What kind of vessel is HOS Explorer?
HOS Explorer is a Offshore Supply Vessel flagged to United States of America.
What is HOS Explorer's MMSI?
HOS Explorer's MMSI is 366899420. Call sign WDB4530. IMO 8964410.
How big is HOS Explorer?
HOS Explorer is about 63 m long, 14 m on the beam, drawing 4.9 m.
Is HOS Explorer on the Master's Mate Safety Initiative Network?
Not yet. If HOS Explorer is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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