Sentences

There are 27 different types of top level messages defined in ITU 1371-4 (out of a possibility of 64) that can be sent by AIS transceivers.

A full list can be downloaded from the download section on the right.

AIS messages 6, 8, 25, and 26 provide “Application Specific Messages” (ASM), that allow “competent authorities” to define additional AIS message sub-types. There are addressed (ABM) and broadcast (BBM) variants of the message.

Addressed messages, while containing a destination MMSI, are not private and may be decoded by any receiver. One of the first uses of ASM’s was the Saint Lawrence Seaway use of AIS binary messages (message type 8) to provide information about water levels, lock orders, and weather. The Panama Canal uses AIS type 8 messages to provide information about rain along the canal and wind in the locks. In 2010, International Maritime Organization issued Circular 289 that defines the next iteration of ASM’s for type 6 and 8 messages.

AIS Ship Types
0 Not available (default)
1-19 Reserved for future use
20 Wing in ground (WIG), all ships of this type
21 Wing in ground (WIG), Hazardous category A
22 Wing in ground (WIG), Hazardous category B
23 Wing in ground (WIG), Hazardous category C
24 Wing in ground (WIG), Hazardous category D
25 Wing in ground (WIG), Reserved for future use
26 Wing in ground (WIG), Reserved for future use
27 Wing in ground (WIG), Reserved for future use
28 Wing in ground (WIG), Reserved for future use
29 Wing in ground (WIG), Reserved for future use
30 Fishing
31 Towing
32 Towing: length exceeds 200m or breadth exceeds 25m
33 Dredging or underwater ops
34 Diving ops
35 Military ops
36 Sailing
37 Pleasure Craft
38 Reserved
39 Reserved
40 High speed craft (HSC), all ships of this type
41 High speed craft (HSC), Hazardous category A
42 High speed craft (HSC), Hazardous category B
43 High speed craft (HSC), Hazardous category C
44 High speed craft (HSC), Hazardous category D
45 High speed craft (HSC), Reserved for future use
46 High speed craft (HSC), Reserved for future use
47 High speed craft (HSC), Reserved for future use
48 High speed craft (HSC), Reserved for future use
49 High speed craft (HSC), No additional information
50 Pilot Vessel
51 Search and Rescue vessel
52 Tug
53 Port Tender
54 Anti-pollution equipment
55 Law Enforcement
56 Spare – Local Vessel
57 Spare – Local Vessel
58 Medical Transport
59 Noncombatant ship according to RR Resolution No. 18
60 Passenger, all ships of this type
61 Passenger, Hazardous category A
62 Passenger, Hazardous category B
63 Passenger, Hazardous category C
64 Passenger, Hazardous category D
65 Passenger, Reserved for future use
66 Passenger, Reserved for future use
67 Passenger, Reserved for future use
68 Passenger, Reserved for future use
69 Passenger, No additional information
70 Cargo, all ships of this type
71 Cargo, Hazardous category A
72 Cargo, Hazardous category B
73 Cargo, Hazardous category C
74 Cargo, Hazardous category D
75 Cargo, Reserved for future use
76 Cargo, Reserved for future use
77 Cargo, Reserved for future use
78 Cargo, Reserved for future use
79 Cargo, No additional information
80 Tanker, all ships of this type
81 Tanker, Hazardous category A
82 Tanker, Hazardous category B
83 Tanker, Hazardous category C
84 Tanker, Hazardous category D
85 Tanker, Reserved for future use
86 Tanker, Reserved for future use
87 Tanker, Reserved for future use
88 Tanker, Reserved for future use
89 Tanker, No additional information
90 Other Type, all ships of this type
91 Other Type, Hazardous category A
92 Other Type, Hazardous category B
93 Other Type, Hazardous category C
94 Other Type, Hazardous category D
95 Other Type, Reserved for future use
96 Other Type, Reserved for future use
97 Other Type, Reserved for future use
98 Other Type, Reserved for future use
99 Other Type, no additional information 

About Reporting interval and Speed:

Ship’s navigation statusReporting interval (Class A target)
Ship at anchor or moored and not moving faster than 3 kts3 min
Ship at anchor or moored and moving at more than 3 kts10 s
0-14 kt speed10 s
0-14 kt speed with course change3 1/3 s
14-23 kt speed6 s
14-23 kt speed with course change2 s
Speed higher than 23 kt2 s
Speed higher than 23 kt with course change2 s
Ship’s navigation statusReporting interval (Class B target)
0-2 kt speed3 min
2-14 kt speed30 s
14-23 kt speed with course change15 s
Speed higher than 23 kt5 s