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
USNS Arrowhead
MMSI 338092000 · Call sign WDN4734
Not yet on Master's MateFlag
USALength
78.7 m
Call sign
WDN4734
IMO
9472373
Official No.
968690
AIS reports
4
USNS Arrowhead, a vessel on the the United States registry, measures 78.7 metres on deck. She's on record as MMSI 338092000, call sign WDN4734, IMO 9472373. Bring USNS Arrowhead aboard the Master's Mate Safety Initiative Network — free, and every captain on it has the others' backs.
Free forever · No credit card
Is USNS Arrowhead 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 USNS Arrowhead 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 USNS Arrowhead 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 USNS Arrowhead and switch it all on
Free to join · nothing to install to start · cancel anytime
About USNS Arrowhead
What kind of vessel is USNS Arrowhead?
USNS Arrowhead is a vessel flagged to United States of America.
What is USNS Arrowhead's MMSI?
USNS Arrowhead's MMSI is 338092000. Call sign WDN4734. IMO 9472373.
How big is USNS Arrowhead?
USNS Arrowhead is about 78.7 m long.
Is USNS Arrowhead on the Master's Mate Safety Initiative Network?
Not yet. If USNS Arrowhead is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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