Cargo ships on AIS

Which AIS codes count as cargo ships

AIS codes 70 to 79 cover every ship that carries freight that is not a liquid in bulk. The tens digit 7 says "cargo ship"; the units digit is a dangerous-goods qualifier, not a subtype. 70 is a cargo ship with no declaration, 71 to 74 declare hazardous-cargo categories A to D, 75 to 78 are reserved, and 79 means "no additional information".

The standard has no separate code for a container ship, a bulk carrier, a reefer or a car carrier. All of them are 70-something. To tell them apart you need the hull dimensions in the static report, the name and IMO number, or a look at the ship itself.

How to spot one on the live map

Cargo ships are the backbone of a busy plot: long straight legs at a steady 10 to 20 knots along shipping lanes, clusters of stationary dots at anchorages outside major ports, and tight rows alongside container and bulk terminals.

A cargo ship holding the same position for days at an anchorage is usually waiting for a berth or for orders, not broken down. Check the navigational status: 1 is at anchor, 5 is moored.

Open the live map → Positions there are the latest known, with their source and age.

Who has to carry AIS

Under SOLAS Chapter V, Regulation 19, AIS is mandatory on ships of 300 gross tonnage and upwards on international voyages, cargo ships of 500 gross tonnage and upwards on domestic voyages, and all passenger ships regardless of size. Those ships fit a Class A transponder, which reports navigational status and repeats its position every 2 to 10 seconds while under way.

The navigational status to expect

Ship type says what a vessel is; navigational status says what it claims to be doing. These are the statuses that normally go with cargo ships:

• 0 · Under way using engine
• 1 · At anchor
• 5 · Moored
• 4 · Constrained by draught

Where the type code misleads

Most crews leave the qualifier at 0 or 9 whatever the ship is carrying. A 70 is not evidence that a ship carries no dangerous goods, and a 71 that never changes between voyages is more likely a setting nobody revisited than a live declaration.

Some offshore supply vessels, heavy-lift ships and project cargo carriers report 70 or 90 more or less interchangeably, so the edges of this category are soft.

Questions

What AIS ship type code is a container ship?

There is no dedicated code. Container ships report a cargo code in the 70 to 79 range, almost always 70, the same as bulk carriers and general cargo ships. The dimensions, name and IMO number are what identify it as a container ship.

What does ship type 71 mean on a cargo ship?

Code 71 is a cargo ship declaring hazardous-cargo category A. Codes 72, 73 and 74 declare categories B, C and D. The declaration is typed in by the crew and is often left unchanged between voyages, so treat it as a claim rather than a manifest.

Why is a cargo ship at anchor for days?

Usually because it is waiting: for a berth, for a pilot or tide window, for cargo, or for orders from its charterer. A long stay at an anchorage is normal commercial behaviour. If the navigational status says moored or at anchor and the speed is near zero, the two agree.

Further reading

• AIS ship type codes explained
• AIS Navigational Status: All 16 Codes Explained
• How AIS actually works
• All 100 AIS ship type codes, one page each
• Port activity index