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.

Passenger (Inspected)

THUNDERBOLT

U.S. Official No. 504467

Not yet on Master's Mate

Type

Passenger (Inspected)

Flag

USA

Length

18.4 m

Beam

4.7 m

Draft

2.4 m

First reported

Jun 2026

AIS reports

Registered in the United States, THUNDERBOLT is an 18.4-metre passenger ferry. Her hull carries a beam measuring 4.7 metres and a draft of 2.4 m. Her papers read U.S. official number 504467. For a boat that carries people, THUNDERBOLT can lean on the Master's Mate Safety Initiative Network — free distress alerting and a fleet that's paying attention.

Free forever · No credit card · for passenger & charter operators

Keep every soul aboard THUNDERBOLT safe.

Distress alerting, live AIS, onboard monitoring and weather routing — the safety stack for boats that carry people.

Switch on the safety stack — free →

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

Wherever THUNDERBOLT 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 passenger & charter operators

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

Joining the Safety Initiative Network doesn't just put THUNDERBOLT on the map. It hands you the full bridge:

Distress Mesh

Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.

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.

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.

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 THUNDERBOLT and switch it all on

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

Claim free → unlock everything

About THUNDERBOLT

What kind of vessel is THUNDERBOLT?

THUNDERBOLT is a Passenger (Inspected) flagged to United States of America.

What is THUNDERBOLT's U.S. Official No.?

THUNDERBOLT's U.S. Official No. is 504467.

How big is THUNDERBOLT?

THUNDERBOLT is about 18.4 m long, 4.7 m on the beam, drawing 2.4 m.

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

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