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.
Tank Barge
PENN NO. 81
MMSI 368237940 · Call sign WDM7858
Not yet on Master's MateType
Tank Barge
Flag
USALength
110.4 m
Beam
22.6 m
Draft
9.4 m
Call sign
WDM7858
Official No.
1231560
AIS reports
1
On the American registry, PENN NO. 81 is an 110.4-metre tank vessel. She has a beam of 22.6 m and a draft measuring 9.4 metres. On AIS she appears as MMSI 368237940, call sign WDM7858. Add PENN NO. 81 to the Master's Mate Safety Initiative Network and share the water with a fleet that's paying attention — free.
Free forever · No credit card · for commercial operators
Eyes on PENN NO. 81, 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 PENN NO. 81 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 PENN NO. 81 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 PENN NO. 81 and switch it all on
Free to join · nothing to install to start · cancel anytime
About PENN NO. 81
What kind of vessel is PENN NO. 81?
PENN NO. 81 is a Tank Barge flagged to United States of America.
What is PENN NO. 81's MMSI?
PENN NO. 81's MMSI is 368237940. Call sign WDM7858.
How big is PENN NO. 81?
PENN NO. 81 is about 110.4 m long, 22.6 m on the beam, drawing 9.4 m.
Is PENN NO. 81 on the Master's Mate Safety Initiative Network?
Not yet. If PENN NO. 81 is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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