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.
Tug
AMERICAN CHALLENGER
MMSI 366873510 · Call sign WDN7328
Not yet on Master's MateType
Tug
Flag
USALength
31 m
Beam
9 m
Call sign
WDN7328
IMO
7420479
Official No.
569788
First reported
Jun 2026
Last reported
Jun 2026
AIS reports
43
AMERICAN CHALLENGER is a working tug wearing American colours, 31 metres overall. She's built with a 9-metre beam. Look for MMSI 366873510, call sign WDN7328, IMO 7420479. The Master's Mate Safety Initiative Network welcomes AMERICAN CHALLENGER — free to join, cruiser-run, and always on watch.
Free forever · No credit card · for working boats
Built for boats that work — like AMERICAN CHALLENGER.
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
Last known position · Jun 3, 2026
Position
21.3211° N, 157.9680° W
Working the Hawaiian Islands? 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 AMERICAN CHALLENGER 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 AMERICAN CHALLENGER and switch it all on
Free to join · nothing to install to start · cancel anytime
About AMERICAN CHALLENGER
What kind of vessel is AMERICAN CHALLENGER?
AMERICAN CHALLENGER is a Tug flagged to United States of America.
Where was AMERICAN CHALLENGER last seen?
AMERICAN CHALLENGER was last reported in the Hawaiian Islands in Jun 2026 on public AIS.
What is AMERICAN CHALLENGER's MMSI?
AMERICAN CHALLENGER's MMSI is 366873510. Call sign WDN7328. IMO 7420479.
How big is AMERICAN CHALLENGER?
AMERICAN CHALLENGER is about 31 m long, 9 m on the beam.
Is AMERICAN CHALLENGER on the Master's Mate Safety Initiative Network?
Not yet. If AMERICAN CHALLENGER is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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