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.
Tanker
AZUMA MARU NO.21
MMSI 431006718 · Call sign JD3873
Not yet on Master's MateType
Tanker
Flag
JPNLength
105 m
Beam
16 m
Draft
4.8 m
Call sign
JD3873
IMO
9758088
First reported
Jun 2026
Last reported
Jun 2026
AIS reports
29
Registered in Japan, AZUMA MARU NO.21 is a 105-metre tank vessel. She carries a 16 m beam and a 4.8 m draft. Look for MMSI 431006718, call sign JD3873, IMO 9758088. AZUMA MARU NO.21 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 commercial operators
Eyes on AZUMA MARU NO.21, 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
Last known position · Jun 2, 2026
Position
39.7975° N, 139.9194° E
Transiting the Sea of Japan? 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 AZUMA MARU NO.21 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 AZUMA MARU NO.21 and switch it all on
Free to join · nothing to install to start · cancel anytime
About AZUMA MARU NO.21
What kind of vessel is AZUMA MARU NO.21?
AZUMA MARU NO.21 is a Tanker flagged to Japan.
Where was AZUMA MARU NO.21 last seen?
AZUMA MARU NO.21 was last reported in the Sea of Japan in Jun 2026 on public AIS.
What is AZUMA MARU NO.21's MMSI?
AZUMA MARU NO.21's MMSI is 431006718. Call sign JD3873. IMO 9758088.
How big is AZUMA MARU NO.21?
AZUMA MARU NO.21 is about 105 m long, 16 m on the beam, drawing 4.8 m.
Is AZUMA MARU NO.21 on the Master's Mate Safety Initiative Network?
Not yet. If AZUMA MARU NO.21 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.