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.
Freight Barge
MST 421
U.S. Official No. 646561
Not yet on Master's MateType
Freight Barge
Flag
USALength
59.5 m
Beam
10.7 m
Draft
3 m
First reported
Jun 2026
AIS reports
1
MST 421, a cargo barge flying the American flag, measures 59.5 metres on deck. She's built with a 10.7 m beam and a 3 m draft. Her registration reads U.S. official number 646561. MST 421 is welcome on the Master's Mate Safety Initiative Network — free situational awareness and a watch network shared by vessels of every size.
Free forever · No credit card · for commercial operators
Eyes on MST 421, around the clock.
Real-time AIS, full systems telemetry, distress alerting and worldwide charts — your hull on one dashboard, from anywhere.
Put her on the dashboard — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Wherever MST 421 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 commercial operators
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put MST 421 on the map. It hands you the full bridge:
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.
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
Worldwide Charts
Navionics-grade vector charts, satellite & raster overlays, online or off. Your whole cruising ground.
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.
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 MST 421 and switch it all on
Free to join · nothing to install to start · cancel anytime
About MST 421
What kind of vessel is MST 421?
MST 421 is a Freight Barge flagged to United States of America.
What is MST 421's U.S. Official No.?
MST 421's U.S. Official No. is 646561.
How big is MST 421?
MST 421 is about 59.5 m long, 10.7 m on the beam, drawing 3 m.
Is MST 421 on the Master's Mate Safety Initiative Network?
Not yet. If MST 421 is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
© 2026 Master’s Mate. All rights reserved.