How to interpret Navigational Status

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

References & Other Resources