Intended route

Introduction/Additional information:

This message allows the communication of a vessels intended route to other vessels and shore stations.

The rules for broadcasting this message are the following
a)      Only broadcast when the vessel is following an activated route.
b)      The route must be broadcast every six minutes, due to what is stated in ITU-R M.1371-4 (§4.2.1) regarding sending interval for voyage related information.
c)       On route activation the route must be broadcast.
d)      When active waypoint changes the route must be broadcast.
e)      On route deactivation, or when a route is completed, an empty message with no waypoints must be sent to indicate that the vessel is not following an intended route.

The broadcast waypoints must start with the current active waypoint and include up to the 15 following waypoints, giving a maximum of 16 waypoints.

Broadcasting 16 waypoints will result in a 5-slot message. It is recommended to avoid messages with more than 3 slots, equivalent to no more than 8 waypoints.

See http://enav.frv.dk/ais_route_suggestion.pdf(link is external) for usage and portrayal details.

Registrant:
Danish Maritime Authority
Message number:
8
DAC:
219
FI:
1
State:
draft
Used by:
Danish Maritime Authority
EfficienSea
Number of slots (max):
3
Reporting Rate:
Every 6 minutes and on active route change
How portrayed:

See http://enav.frv.dk/ais_route_suggestion.pdf(link is external) for usage and portrayal details.

Permitted as from:
03/11/2011
Technical point of contact:

Jens Kristian Jensen
Danish Maritime Authority
JKJ@dma.dk(link sends e-mail)

Details:

Table 2.1
Intended route (broadcast)

Parameter No. Of bits Description
Message ID 6 Identifier for Message 8; always 8.
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.
Spare 1 Not used. Set to zero.
IAI 16 DAC = 219; FI = 1
ETA active WP   The ETA at the active waypoint (first waypoint). For a cancellation of active route, the default values can be used.
UTC Month 4 1 – 12
0 = not available = default
UTC Day 5 1 – 31
0 = not available = default
UTC Hour 5 0 – 23
0 = not available = default
UTC Minute 6 0 – 59
0 = not available = default
Duration 18 Minutes from ETA at active waypoint to ETA at the last broadcast waypoint. The duration allows for the calculation of an average intended speed on the broadcast route.

0 = not available = default

Number of Waypoints 5 Number of Waypoints

1  – 16

0 = no active route = cancel route

17 – 31 (not used)

Waypoints n x 55 Variable number of waypoints 0 – 16 (55 bit each), refer to table 2.2.
Spare   Not used. Set to zero.
Total 99 – 979 Occupies 2 – 5 slots.

1 – 4 waypoints = 2 slots

5 – 8 waypoints = 3 slots

9 – 12 waypoints = 4 slots

13 – 16 waypoints = 5 slots

 

Table 2.2
Waypoints

Parameter No. Of bits Description
WP Longitude 28 Longitude in 1/10,000 min, ±180 degrees as per 2’s complement

(East = positive, West = negative).

WP Latitude 27 Latitude in 1/10,000 min, ±90 degrees as per 2’s complement

(North = positive, South = negative).