THUNDER BAY — Tug · IMO 8635203

THUNDER BAY has not broadcast an AIS position for 3 days. The most recent broadcast placed it in the North Atlantic Ocean, on 4 Nov 2026, 14:57 UTC. It was sailing from DAVISVILLE to ROCKLAND. Vessels stop appearing on terrestrial AIS when they move beyond receiver range, so a gap does not necessarily mean the vessel is inactive.

THUNDER BAY broadcasts MMSI 366999983 and is registered as IMO 8635203, with call sign NNTB. The MMSI is the radio identifier used by AIS; the IMO number stays with the ship for life and does not change with re-flagging or sale.

THUNDER BAY is classified as a tug vessel registered under the US flag. The vessel-type classification is derived from the AIS Type field broadcast by the ship's transponder; full tug fleet at /vessel-type/tug-pilot-vessel and full US flag list at /flag/us.

MarineRadar shows the latest AIS broadcast from THUNDER BAY above, with current position, course, speed, and navigation status. Tap "View on map" to centre the live tracker on the vessel and watch its movement update in real time. The same data is available offline-friendly in the iOS and Android apps.

AIS transponders broadcast position every 2 seconds when underway at high speed and up to every 3 minutes at anchor. The position you see refreshes whenever the ship is in range of a coastal AIS receiver or a satellite pass — typically seconds in coastal waters and minutes offshore.

As a tug, THUNDER BAY sits in the same design class as the other tugs listed in the Similar Vessels section of the vessel page, or in the full tug directory at /vessel-type/tug-pilot-vessel. THUNDER BAY has a gross tonnage of 500 GT.