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.

Recreational

THUNDERHEAD

MMSI 366903750 · Call sign WDB4915

Not yet on Master's Mate

Type

Recreational

Flag

USA

Length

13.6 m

Beam

4 m

Draft

2 m

Call sign

WDB4915

Official No.

286446

AIS reports

THUNDERHEAD is a private cruiser flagged in the United States, 13.6 metres long. She has a 4 m beam and a draft of 2 m. She's listed under MMSI 366903750, call sign WDB4915. Whether she's at the dock or out for the weekend, THUNDERHEAD is covered by the free Master's Mate Safety Initiative Network — alarms, weather, and a watching fleet.

Free forever · No credit card · for recreational captains

Keep THUNDERHEAD looked after — even when you’re not aboard.

Anchor alarms that wake you, a live camera at the dock, and weather you can trust before every run.

Look after her — claim free →

Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers

Wherever THUNDERHEAD 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 recreational captains

The most powerful cruising platform ever built — yours, free.

Joining the Safety Initiative Network doesn't just put THUNDERHEAD 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.

Onboard Cameras

Watch your boat from anywhere — live feeds and 24h recording, straight from your gateway.

Weather & Routing

GRIB wind, swell & current on the chart. Plan passages with ETA-calibrated forecasts per leg.

Worldwide Charts

Navionics-grade vector charts, satellite & raster overlays, online or off. Your whole cruising ground.

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.

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 THUNDERHEAD and switch it all on

Free to join · nothing to install to start · cancel anytime

Claim free → unlock everything

About THUNDERHEAD

What kind of vessel is THUNDERHEAD?

THUNDERHEAD is a Recreational flagged to United States of America.

What is THUNDERHEAD's MMSI?

THUNDERHEAD's MMSI is 366903750. Call sign WDB4915.

How big is THUNDERHEAD?

THUNDERHEAD is about 13.6 m long, 4 m on the beam, drawing 2 m.

Is THUNDERHEAD on the Master's Mate Safety Initiative Network?

Not yet. If THUNDERHEAD is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).