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.
Towing Vessel
Johnny C
MMSI 366910420 · Call sign WDB5509
Not yet on Master's MateType
Towing Vessel
Flag
USALength
17.5 m
Beam
6.7 m
Draft
2.9 m
Call sign
WDB5509
Official No.
500523
AIS reports
1
Johnny C is an American 17.5-metre utility boat. Johnny C has a 6.7 m beam and a 2.9-metre draft. Look for MMSI 366910420, call sign WDB5509. Add Johnny C to the Master's Mate Safety Initiative Network — free to join, and the fleet keeps an eye out for each other.
Free forever · No credit card · for working boats
Built for boats that work — like Johnny C.
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
Wherever Johnny C 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 working boats
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put Johnny C 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 Johnny C and switch it all on
Free to join · nothing to install to start · cancel anytime
About Johnny C
What kind of vessel is Johnny C?
Johnny C is a Towing Vessel flagged to United States of America.
What is Johnny C's MMSI?
Johnny C's MMSI is 366910420. Call sign WDB5509.
How big is Johnny C?
Johnny C is about 17.5 m long, 6.7 m on the beam, drawing 2.9 m.
Is Johnny C on the Master's Mate Safety Initiative Network?
Not yet. If Johnny C is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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