Interpreting the Navigational Status (0-15) in an AIS message.
What is navigational status?
Ships broadcast their navigational status within position message types 1, 2, 3 and 27. It can take on a value from 0 to 15, and each number represents a unique piece of metadata associated with the vessel's activity. We provide this value within the status field.
What does each number mean?
- 0 : Under way using its engine
- 1 : Anchored
- 2 : Not under command
- 3 : Has restricted maneuverability
- 4 : Ship draught is limiting its movement
- 5 : Moored (tied to another object to limit free movement)
- 6 : Aground
- 7 : Engaged in fishing
- 8 : Under way sailing
- 9 : (Number reserved for modifying reported status of ships carrying dangerous goods/harmful substances/marine pollutants)
- 10 : (Number reserved for modifying reported status of ships carrying dangerous goods/harmful substances/marine pollutants)
- 11 : Power-driven vessel towing astern
- 12 : Power-driven vessel pushing ahead/towing alongside
- 13 : (Reserved for future use)
- 14 : Any of the following are active: AIS-SART (Search and Rescue Transmitter), AIS-MOB (Man Overboard), AIS-EPIRB (Emergency Position Indicating Radio Beacon)
- 15 : Undefined (default)
Below is a table of decoded navigation status values reported by vessels and returned as the decoded values by Spire Vessels API. Sample taken 2020-01-05
| # | navigational_status | mmsi_count | imo_count |
| 1 | 85332 | 676 | |
| 2 | AIS-SART (active), MOB-AIS, EPIRB-AIS | 25 | 11 |
| 3 | Aground | 138 | 50 |
| 4 | At anchor | 24618 | 18226 |
| 5 | Constrained by her draught | 372 | 217 |
| 6 | Engaged in fishing | 2738 | 1017 |
| 7 | Moored | 37135 | 24191 |
| 8 | Not under command | 1209 | 1036 |
| 9 | Power-driven vessel pushing ahead or towing alongside | 789 | 124 |
| 10 | Power-driven vessel towing astern | 203 | 114 |
| 11 | Reserved for future amendment of navigational status for ships carrying DG, HS, or MP, or IMO hazard or pollutant category C, high speed craft (HSC) | 193 | 84 |
| 12 | Reserved for future amendment of navigational status for ships carrying dangerous goods (DG), harmful substances (HS) or marine pollutants (MP), or IMO hazard or pollutant category A, wing in ground (WIG) | 93 | 47 |
| 13 | Reserved for future use | 82 | 27 |
| 14 | Restricted maneuverability | 2047 | 1586 |
| 15 | Undefined | 87789 | 51115 |
| 16 | Under way sailing | 2965 | 1920 |
| 17 | Under way using engine | 70872 | 42180 |