AIS navigational status
AIS navigational status 12: Power-driven vessel pushing ahead or towing alongside
Pushing a barge or towing on the hip. What status 12 means, what speed and track should go with it, and how often it is simply wrong.
What status 12 means
A power-driven vessel pushing another ahead of it, or towing a vessel made fast alongside. Same late vintage as code 11, with the same patchy adoption.
What should go with it
Slow, steady speed — pusher-barge units are common on rivers and in some ports.
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
As with 11, absence means little; many pushers report 0. A pushed barge unit rigidly connected is treated as one power-driven vessel under the rules.
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 24(c) — two masthead lights in a vertical line, sidelights and sternlight 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.