Message ID

6

Identifier for this Message 1

Repeat indicator

2

Used by the repeater to indicate how many times a message has been repeated. See § 4.6.1, Annex 2; 0-3; 0 = default; 3 = do not repeat any more

User ID

30

Unique identifier such as MMSI number

Navigational status

4

 0 = under way using engine
 1 = at anchor
 2 = not under command
 3 = restricted maneuverability
 4 = constrained by her draught
 5 = moored
 6 = aground
 7 = engaged in fishing
 8 = under way sailing
 9 = 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)
10 = 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)
11 = power-driven vessel towing astern (regional use)
12 = power-driven vessel pushing ahead or towing alongside (regional use)
13 = reserved for future use,
14 = AIS-SART (active), MOB-AIS, EPIRB-AIS
15 = undefined = default (also used by AIS-SART, MOB-AIS and EPIRB-AIS under test)

Rate of turn
ROTAIS

8

0 to +126 = turning right at up to 708° per min or higher
0 to –126 = turning left at up to 708° per min or higher

Values between 0 and 708° per min coded by ROTAIS = 4.733 SQRT(ROTsensor) degrees per min where ROTsensor is the Rate of Turn as input by an external Rate of Turn Indicator (TI). ROTAIS is rounded to the nearest integer value.
+127 = turning right at more than 5° per 30 s (No TI available)
–127 = turning left at more than 5° per 30 s (No TI available)
–128 (80 hex) indicates no turn information available (default).
ROT data should not be derived from COG information.

SOG

10

Speed over ground in 1/10 knot steps (0-102.2 knots)
1 023 = not available, 1 022 = 102.2 knots or higher

Position accuracy

1

The position accuracy (PA) flag should be determined in accordance with Table 50
1 = high (≤ 10 m)
0 = low (>10 m)
0 = default

Longitude

28

Longitude in 1/10 000 min (±180°, East = positive (as per 2’s complement), West = negative (as per 2’s complement).
181 = (6791AC0h) = not available = default)

Latitude

27

Latitude in 1/10 000 min (±90°, North = positive (as per 2’s complement), South = negative (as per 2’s complement). 91° (3412140h) = not available = default)

COG

12

Course over ground in 1/10 = (0-3 599). 3 600 (E10h) = not available = default. 3 601-4 095 should not be used

True heading

9

Degrees (0-359) (511 indicates not available = default)

Time stamp

6

UTC second when the report was generated by the electronic position system (EPFS) (0-59, or 60 if time stamp is not available, which should also be the default value, or 61 if positioning system is in manual input mode, or 62 if electronic position fixing system operates in estimated (dead reckoning) mode, or 63 if the positioning system is inoperative)

Special manoeuvre indicator

2

0 = not available = default
1 = not engaged in special manoeuvre
2 = engaged in special manoeuvre
(i.e. regional passing arrangement on Inland Waterway)

Spare

3

Not used. Should be set to zero. Reserved for future use.

RAIM-flag

1

Receiver autonomous integrity monitoring (RAIM) flag of electronic position fixing device; 0 = RAIM not in use = default; 1 = RAIM in use. See Table 50

Communication state

19

See Table 49

Number of bits

168

1

SOTDMA communication state as described in § 3.3.7.2.2, Annex 2

2

SOTDMA communication state as described in § 3.3.7.2.2, Annex 2

3

ITDMA communication state as described in § 3.3.7.3.2, Annex

Parameter

Number of bits

Description

Sync state

2

0     UTC direct (see § 3.1.1.1)
1     UTC indirect (see § 3.1.1.2)
2     Station is synchronized to a base station (base direct) (see § 3.1.1.3)
3     Station is synchronized to another station based on the highest number of received stations or to another mobile station, which is directly synchronized to a base station
(see § 3.1.1.3 and § 3.1.1.4)

Slot time-out

3

Specifies frames remaining until a new slot is selected
0     means that this was the last transmission in this slot
1-7  means that 1 to 7 frames respectively are left until slot change

Sub message

14

The sub message depends on the current value in slot time-out as described in Table 19

3, 5, 7

Received stations

Number of other stations (not own station) which the station currently is receiving (between 0 and 16 383).

2, 4, 6

Slot number

Slot number used for this transmission (between 0 and 2 249).

1

UTC hour and minute

If the station has access to UTC, the hour and minute should be indicated in this sub message. Hour (0-23) should be coded in bits 13 to 9 of the sub message (bit 13 is MSB). Minute (0-59) should be coded in bit 8 to 2 (bit 8 is MSB). Bit 1 and bit 0 are not used.

0

Slot offset

If the slot time-out value is 0 (zero) then the slot offset should indicate the offset to the slot in which transmission will occur during the next frame. If the slot offset is zero, the slot should be de-allocated after transmission.

No RAIM process available

0

Uncorrected

0 = low (>10 m)

EXPECTED RAIM error is ≤ 10 m

1

1 = high (≤10 m)

EXPECTED RAIM error is > 10 m

1

0 = low (>10 m)

No RAIM process available

0

Corrected

1 = high (≤10 m)

EXPECTED RAIM error is ≤ 10 m

1

1 = high (≤10 m)

EXPECTED RAIM error is > 10 m

1

0 = low (>10 m)

1. The connected GNSS receiver indicates the availability of a RAIM process by a valid sentence of IEC 61162; in this case the RAIM-flag should be set to “1”. The threshold for evaluation of the RAIM information is 10 m. The RAIM expected error is calculated based on “expected error in latitude” and “expected error in longitude” using the following formula:
2. The quality indicator in the position sentences of IEC 61162 received from the connected GNSS receiver indicates the correction status.