Ships' Information and Communications Systems After 9/11

Immediately after 9/11, the U.S. was able to influence the International Maritime Organization's (IMO) International Convention for the Safety of Life at Sea (SOLAS) to require Automatic Identification System (AIS) to be fitted aboard internationally-trading ships of 300 or more gross tonnage, and all passenger ships regardless of size. It is estimated that more than 50,000 ships currently carry AIS class A equipment. The AIS is a system used by ships and Vessel Traffic Services (VTS) principally for identification and locating other vessels. AIS provides a means for ships to electronically exchange ship data including: identification, position, course, and speed, with other nearby ships and VTS stations. This information can be displayed on a screen or chart plotter. AIS is intended to assist the vessel's watchstanding officers and allow maritime authorities to track and monitor vessel movements. It works by integrating a standardized VHF transceiver system with an electronic navigation system, such as a LORAN-C (LOng RAnge Navigation Version C) or Global Positioning System (GPS) receiver, and other navigational sensors on board ship (gyrocompass, rate of turn indicator, etc.).

When a ship is navigating at sea, the movement and identity of other ships in the vicinity is critical for navigators to make decisions to avoid collision with other ships and dangers (shoal or rocks). Visual observation (unaided, binoculars, night vision), audio exchanges (whistle, horns, VHF radio), and radar or Automatic Radar Plotting Aid (ARPA) are historically used for this purpose. However, a lack of positive identification of the targets on the displays, and time delays and other limitation of radar for observing and calculating the action and response of ships around, especially on busy waters, sometimes prevent possible action in time to avoid collision. While requirements of AIS are only to display very basic text information, the data obtained can be integrated with a graphical electronic chart or a radar display, providing consolidated navigational information on a single display.

AIS transponders automatically broadcast information, such as their position, speed, and navigational status, at regular intervals via a VHF transmitter built into the transponder. The information originates from the ship's navigational sensors, typically its global navigation system (GNSS) receiver and gyrocompass. Other information, such as the vessel name and VHF call sign, is programmed when installing the equipment and is also transmitted regularly. The signals are received by AIS transponders fitted on other ships or on land based systems, such as VTS systems. The received information can be displayed on a screen or chart plotter, showing the other vessels' positions in much the same manner as a radar display. Now, that is the good part.

In relation to the issue of freely available AIS-generated ship data on the world-wide web, the publication on the world-wide web or elsewhere of AIS data transmitted by ships could be detrimental to the safety and security of ships and port facilities and was undermining the efforts of the IMO and its Member States to enhance the safety of navigation and security in the international maritime transport sector. So now, pirates, terrorists and enemy ships have a better grasp on very vital information concerning multi-million dollar ships and their cargo worldwide. And that is really bad.