AIS navigational status
AIS navigational status 1: At anchor
Holding position on its own anchor. What status 1 means, what speed and track should go with it, and how often it is simply wrong.
What status 1 means
The vessel is anchored. Large numbers of status-1 ships off a port are an anchorage queue: ships waiting for a berth, for orders or for a cargo.
What should go with it
Under about 0.5 kn, with the heading slowly swinging as wind and tide move the ship around its anchor.
Navigational status is entered by hand on the bridge; speed, course and position come from a satellite receiver. Read the status as testimony and the rest as measurement. Where they agree you have learned something. Where they disagree, the measurement is usually right.
How it goes wrong
The status is often left on 1 after the anchor comes up, so a ship can be making 12 kn while still "at anchor". If speed and status disagree, trust the speed.
The matching lights and shapes
The AIS status mirrors a state defined in the International Regulations for Preventing Collisions at Sea (COLREGs), which also say what the vessel should display:
Rule 30 — one ball by day; all-round white anchor light(s) at night.
Summary for orientation only. The COLREGs text is the authority; this site is not a navigation reference.
All sixteen codes
| Code | Meaning |
|---|---|
| 0 | Under way using engine |
| 1 | At anchor |
| 2 | Not under command |
| 3 | Restricted manoeuvrability |
| 4 | Constrained by her draught |
| 5 | Moored |
| 6 | Aground |
| 7 | Engaged in fishing |
| 8 | Under way sailing |
| 9 | Reserved for future amendment (HSC) |
| 10 | Reserved for future amendment (WIG) |
| 11 | Power-driven vessel towing astern |
| 12 | Power-driven vessel pushing ahead or towing alongside |
| 13 | Reserved for future use |
| 14 | AIS-SART, MOB-AIS or EPIRB-AIS active |
| 15 | Undefined (default) |
For the field as a whole — and how this site handles it — read AIS navigational status codes, all sixteen.