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Tidal window

Introduction/Additional information: 
This message should be used to inform vessels about tidal windows which allow a vessel the safe passage of a fairway.
Permitted as from: 
01/06/2010
Registrant: 
IMO Circ. 289
Physical link: 
AIS
Message number (0=VDES-VDE): 
6
DAC or VPFI: 
1
FI / Message ID: 
32
State: 
in force
State link: 
Tidal window
Number of slots (max): 
3
Last modified: 
29/01/2021 - 23:18
Details: 
Parameter  No. of bits  Description 
Message ID  6 Identifier for Message 6; always 6. 
Repeat Indicator  2 Used by the repeater to indicate how many times a message has been repeated.
0 - 3
0 = default
3 = do not repeat anymore 
Source ID  30 MMSI number of source station 
Sequence Number  2 0 - 3; refer to ITU-R M.1371-3, Annex 2, § 5.3.1 
Destination ID  30 MMSI number of destination station. 
Retransmit Flag  1 Retransmit Flag should be set upon retransmission.
0 = no retransmission = default
1 = retransmitted 
Spare  1 Not used. Set to zero. 
IAI  16 DAC = 001; FI =32 
Time Stamp  UTC Day    UTC date of the data.
UTC Month 4 1 - 12
0 = not available = default
UTC Day  5 1 - 31
0 = not available = default 
Position #1 Longitude  25 Longitude in 1/1,000 min, ±180 degrees as per 2's complement (East = positive, West = negative).
181 = not available = default 
Position #1 Latitude  24 Latitude in 1/1,000 min, ±90 degrees, as per 2's complement (North = positive, South = negative).
91 degrees = not available = default 
From UTC Hour  5 0 - 23
24 = not available = default 
From UTC Minute  6 0 - 59
60 = not available = default 
To UTC Hour  5 0 - 23
24 = not available = default 
To UTC Minute  6 0 - 59
60 = not available = default 
Current Direction predicted #1  9 Direction of Current 1, in 1 degree steps.
0 - 359 degrees
360 = not available = default
361-511 (do not use) 
Current Speed predicted #1  8 Speed of Current 1, in 0.1 knot steps.
0.0 – 25.0 knots
251 = speed 25.1 knots or greater
252 – 254 (reserved for future use)
255 = not available = default 
Position #2 Longitude  25 Longitude in 1/1,000 min, ±180 degrees as per 2's complement (East = positive, West = negative).
181 = not available = default 
Position #2 Latitude  24 Latitude in 1/1,000 min, ±90 degrees as per 2's complement (North = positive, South = negative).
91 degrees = not available = default 
From UTC Hour  5 0 - 23 24 = not available = default 
From UTC Minute  6 0 - 59 60 = not available = default 

Notice from webmaster:
In this prediction the To UTC Hour and to UTC Minute is missing.

    
Current Direction predicted #2  9 Direction of Current 2, in 1 degree steps.
0 - 359 degrees
360 = not available = default
361-511 (do not use) 
Current Speed predicted #2  8 Speed of Current 2, in 0.1 knot steps. 0.0 – 25.0 knots
251 = speed 25.1 knots or greater.
252 - 254 (reserved for future use)
255 = not available = default 

Position #2 Longitude

Notice from the webmaster:
#2 should be #3 

 25 Longitude in 1/1,000 min, ±180 degrees as per 2's complement (East = positive, West = negative).
181 = not available = default 
Position #3 Latitude  24 Latitude in 1/1,000 min, ±90 degrees as per 2's complement
(North = positive, South = negative).
91 degrees = not available = default 
From UTC Hour  5 0 - 23
24 = not available = default 
From UTC Minute  6 0 - 59
60 = not available = default 
To UTC Hour  5 0 - 23
24 = not available = default 
To UTC Minute  6 0 - 59
60 = not available = default 
Current Direction predicted #3  9 Direction of Current 3, in 1 degree steps.
0 - 359 degrees
360 = not available = default
361 - 511 (not used) 
Current Speed predicted #3  8 Speed of Current 3, in 0.1 knot steps.
0.0 - 25.0 knots
251 = speed 25.1 knots or greater
252 - 254 (reserved for future use)
255 = not available = default 
Total  350 occupies 3 slots