Advice of waypoints (AWP) and/or route plan of VTS

Introduction/Additional information:

This IFM should be used by a VTS to advise its waypoints and/or its route plan. If the VTS uses this IFM 18 within an addressed binary message, then the waypoints and/or the route plan will be available to the addressed recipient, one ship, only. If the VTS uses this IFM 18 within a broadcast binary message, then the information will be available to all other ships in the VTSs vicinity.
When transmitting, the VTS should include up to 12 advised waypoints and/or a route specified by a textual description, if available. If waypoints are transmitted, then a recommended turning radius may be transmitted for each waypoint.

Permitted as from:

01/01/1998

Not to be used after:

01/01/1998

Registrant:

ITU-R.M.1371-1

Physical link:

AIS

Message number (0=VDES-VDE):

DAC or VPFI:

FI / Message ID:

State:

deprecated

Number of slots (max):

Last modified:

29/01/2021 - 23:18

Details:

	Number of bits		Description
AWP	4		Number of advised waypoints (1-12); 0 = no waypoint = default; 12-15 = not used
WP i.Lon	28		Longitude of advised waypoint i in 1/10 000 min (±180°, East = positive, West = negative). Field required if and as often as 1 ≤ i ≤ AWP, i = 1, 2, 3, ..., 12; field not required if AWP = 0
WP i.Lat	27		Latitude of advised waypoint i in 1/10 000 min (±90°, North = positive, South = negative). Field required if and as often as 1 ≤ i ≤ AWP, i = 1, 2, 3, ..., 12; field not required if AWP = 0
Advised turning radius i	12		Advised turning radius at advised waypoint i in metres; 0 = not available = default; 1-4 095 m. Field required if and as often as 1 ≤ i ≤ AWP, i = 1, 2, 3, ..., 12; field not required if AWP = 0
Advised route specified by textual description	120		Description of the advised route in textual form, e.g. —west channel“; maximum 20 characters using 6-bit ASCII; @@@@@@@@@@@@@@@@@@@@ = not available (field must not be omitted)
Spare	AWP	Bits	Spare. Not used. Should be set to zero
	0, 8	4
	1, 9	1
	2, 10	6
	3, 11	3
	4, 12	0
	5	5
	6	2
	7	7
Number of bits	128-928		The number of bits of the IFM 17 may be calculated as follows: 124 + (AWP × 67) + spare

Number of next waypoints transmitted	0	1	2	3	4	5	6	7	8	9	10	11	12	13	14
Number of slots used for this message	2	2	2	3	3	3	3	4	4	4	4	5	5	5	5