Regulation 19 of SOLAS Chapter V (Carriage requirements for ship borne navigational systems and equipment) sets out navigational equipment to be carried on board ships, according to ship type. The regulation requires AIS to be fitted aboard all ships of 300 gross tonnage and upwards engaged on international voyages, cargo ships of 500 gross tonnage and upwards not engaged on international voyages and all passenger ships irrespective of size. The requirement became effective for all ships by 31 December 2004.
IMO Resolution MSC.74 (69) Annex 3, adopted on 12th May 2008 provides the Recommendation on Performance Standards For an Universal Ship borne AIS.
These performance standards specify the requirements for the universal AIS.
1. The AIS should improve the safety of navigation by assisting in the efficient navigation of ships, protection of the environment, and operation of Vessel Traffic Services (VTS), by satisfying the following functional requirements:
(a) in a ship-to-ship mode for collision avoidance;
(b) as a means for littoral States to obtain information about a ship and its cargo; and
(c) as a VTS tool, i.e. ship-to-shore (traffic management).
2. The AIS should be capable of providing to ships and to competent authorities, information from the ship, automatically and with the required accuracy and frequency, to facilitate accurate tracking. Transmission of the data should be with the minimum involvement of ship’s personnel and with a high level of availability.
3. The installation, in addition to meeting the requirements of the Radio Regulations, applicable ITU-R. Recommendations and the general requirements as set out in resolution A.694 (17), should comply with the following performance standards.
4. The system should be capable of operating in a number of modes:
(a) an “autonomous and continuous” mode for operation in all areas. This mode should be capable of being switched to/from one of the following alternate modes by a competent authority;
(b) an “assigned” mode for operation in an area subject to a competent authority responsible for traffic monitoring such that the data transmission interval and/or time slots may be set remotely by that authority; and
(c) a “polling” or controlled mode where the data transfer occurs in response to interrogation from a ship or competent authority.
5. The AIS should comprise:
(a) a communication processor, capable of operating over a range of maritime frequencies, with an appropriate channel selecting and switching method, in support of both short and long range applications;
(b) a means of processing data from an electronic position-fixing system which provides a resolution of one ten thousandth of a minute of arc and uses the WGS-84 datum.;
(c) a means to automatically input data from other sensors meeting the provisions as specified in paragraph 6.2;
(d) a means to input and retrieve data manually;
(e) a means of error checking the transmitted and received data; and
(f) built in test equipment (BITE).
6. The AIS should be capable of:
(a) providing information automatically and continuously to a competent authority and other ships, without involvement of ship’s personnel;
(b) receiving and processing information from other sources, including that from a competent authority and from other ships;
(c) responding to high priority and safety related calls with a minimum of delay; and
(d) providing positional and manoeuvring information at a data rate adequate to facilitate accurate tracking by a competent authority and other ships.
7. To enable a user to access, select and display the information on a separate system, the AIS should be provided with an interface conforming to an appropriate international marine interface standard.
8. For the purpose of ship and message identification, the appropriate Maritime Mobile Service Identity (MMSI) number should be used.
9. The information provided by the AIS should include
– IMO number (where available)
– Call sign & name
– Length and beam
– Type of ship
– Location of position-fixing antenna on the ship (aft of bow and port or starboard of centerline)
– Ship’s position with accuracy indication and integrity status
– Time in UTC*
– Course over ground
– Speed over ground
– Navigational status (e.g. NUC, at anchor, etc. – manual input)
– Rate of turn (where available)
– Optional – Angle of heel
– Optional – Pitch and roll
(c) Voyage related:
– Ship’s draught
– Hazardous cargo (type)
– Destination and ETA (at masters discretion)
– Optional – Route plan (waypoints)
(d) Short safety-related messages
10. Information update rates for autonomous mode
The different information types are valid for a different time period and thus need a different update rate:
– Static information: Every 6 min and on request
– Dynamic information: Dependant on speed and course alteration according to Table 1
– Voyage related information: Every 6 min, when data has been amended and on request
– Safety-related message: As required
Ship reporting capacity: the system should be able to handle a minimum of 2000 reports per min to adequately provide for all operational scenarios envisioned.
A security mechanism should be provided to detect disabling and to prevent unauthorized alteration of input or transmitted data. To protect the unauthorized dissemination of data, the IMO guidelines
(Guidelines and Criteria for Ship Reporting Systems*) should be followed.
Permissible initialization period
12. The installation should be operational within 2 min of switching on.
13. The AIS and associated sensors should be powered from the ship’s main source of electrical energy. In addition, it should be possible to operate the AIS and associated sensors from an alternative source of electrical energy.
14. The technical characteristics of the AIS such as variable transmitter output power, operating frequencies (dedicated internationally and selected regionally), modulation, and antenna system should comply with the appropriate ITU-R Recommendations.