AIS FAQs

Automatic Identification Systems (AIS) technology relies upon global navigational positioning systems, shipboard sensors, and digital VHF radio communication equipment operating according to standardized digital communication protocols that permit the voiceless exchange of navigation information between vessels and shore-side vessel traffic centers. The information is continually updated in near real-time and received by all AIS-equipped ships and shore stations in its vicinity.

The AIS provides mariners with accurate navigation information, such as the AIS Static Information Vessel call sign, name, IMO identification number, dimensions, type, Voyage-Related Information Draft, cargo type, destination, estimated     time of arrival, Dynamic Information Time in universal time, coordinated, latitude/longitude position, course over ground, speed over ground, heading, rate of turn, navigational status. 

By increasing the Coast Guard's awareness of vessels in the maritime domain, especially vessels approaching U.S. ports. The AIS corroborates and provides identification and position of vessels not always possible through voice radio communication or radar alone.

The U.S. Coast Guard has developed rules applicable to both U.S. and foreign-flag vessels that require owners and operators of most commercial vessels to install and use the AIS. The AIS rule is part of our domestic and international effort to increase the security and safety of maritime transportation.

AIS Regulations became effective November 21, 2003. All vessels required to have an AIS as denoted in 33 CFR - 164.46(a), must have a USCG "'type-approved" and "properly installed" AIS on the vessel no later than December 31, 2004.

Owners and operators of U.S. or foreign-flagged vessels in commercial service who meet the applicability provisions are affected. Please refer to See 33 CFR, Part 164.46 and 33 CFR Part 161.20 for specific regulations.

Vessels on international voyage must install the AIS as specified in the SOLAS Regulation V/19.2.4 implementation schedule adopted by the International Maritime Organization, 31 December 2004; as do vessels on domestic voyage within a U.S. Vessel Movement Reporting System or Vessel Traffic Service Area.

Vessels equipped with AIS (either by mandatory carriage or voluntarily) must abide by the requirements set forth in Title 33, Code of Federal Regulations, 164.46 and 161.20, and should especially ensure their AIS is in effective operating condition, which entails the continuous operation of AIS and the accurate input and upkeep of AIS data fields during all times that the vessel is navigating (underway or at anchor).       

No.  There always will be ships without AIS onboard.  Radar detects targets independent of the targets onboard-equipment.

In addition to radar, AIS has following benefits:  Automatic and immediate vessel identification, Improved vessel tracking (no track swap), Wider geographical coverage, Greater positional accuracy, Absence of radar shadow area, Real time maneuvering data.         

Other than a power loss the proper operation and information validity requires a verification from another AIS station.                

AIS is mainly for monitoring other ships and allows only the transmission of safety related messages on AIS designated frequencies.     

It depends on regulations of the national maritime administrations (port state control).  According to SOLAS Ch.V Reg.16 the vessel is allowed to proceed to a port where repairs can be carried out.        

This information does not give an accurate indication of the actual path of the vessel.  The rudder is just a tool to get the ship to start a turn.  Due to shallow water, constellation of propellers, one or two rudders, open or closed skegg, dynamically stable or unstable ship as well as wind direction, the rudder angle could be very ambiguous

Type approved AIS-capable radars do not exist yet.  Manufacturers are  the best source of information on this burgeoning state of the art.               

Using appropriate symbology.

The accuracy of nautical information, such as position, speed etc., depends on the accuracy of the sensors used.  There is an indication about the accuracy transmitted by AIS.  Further data accuracy, as voyage related data, depends on the accuracy this data is typed in.    

This would introduce the question of revising the collision regulations, which would be a lengthy process.  That is likely after vessels officers are trained in using it in conjunction with COLREG.          

Depends on the onboard installation.

Where the master believes it is necessary for the safety of the crew and/or the vessel and/or the cargo.

Yes

 Accident investigation, traffic monitoring, planning and optimizing statistics.

No.  They are outside the SOLAS Convention, but Administrations may dictate naval vessel use of AIS.

The secondary radar option (used by aviation) was rejected by the radar manufacturers, because it was thought it would add too much cost to the radar installations on ships.     

Class B is intended to be a simpler, less expensive version for the use transponders on non-SOLAS vessels.

Regulations for non-SOLAS vessels are a matter for Administrations.

No

AIS co-ordinates are in WGS-84, the co-ordinate system used by GPS." 

This is a matter for Administrations to police.

This is a matter for Administrations.       

ITU-R recommendation M.1371-1 limits AIS transmission on AIS designated channels to maritime safety related messages.                

Some messages are defined; others have limited capacity for text content.

That is likely; however, commercial messages cannot be transmitted on designated, safety related frequencies, e.g. AIS1 and AIS2.

This is a matter for national administrations to police.

Yes, all sensor information ought to be integrated on a single display.

 Yes, if Administration decides to do so, the message structure and technical approach are defined.       

There are prototype ways to display, a message structure is being proposed to IMO.

No.        

This is a matter for Administrations.

Yes, to comply with the international standard's approval use the certified equipment from ACR Electronics.

Yes, ACR offers training on demand with certificates for participants.

Automatic Identification Systems (AIS) technology relies upon global navigational positioning systems, shipboard sensors, and digital VHF radio communication equipment operating according to standardized digital communication protocols that permit the voiceless exchange of navigation information between vessels and shore-side vessel traffic centers. The information is continually updated in near real-time and received by all AIS-equipped ships and shore stations in its vicinity.

The AIS provides mariners with accurate navigation information, such as:

• Static Information-Vessel call sign, name, IMO identification number, dimensions, type;
• Voyage-Related Information-Draft, cargo type, destination, and estimated time of arrival; and
• Dynamic Information-Time in universal time, coordinated, latitude/longitude position, course over ground, speed over ground, heading, rate of turn, navigational status.

In addition, shore stations will be able to relay pertinent navigational data from other sources, such as the National Oceanic and Atmospheric Administration's Physical Oceanographic Real Time System (PORTS) and U.S. Coast Guard Vessel Traffic Centers. The advantage of an automatic and continuous exchange of information is that all can access it and since it is digital data, software can be modified to the mariner's requirements by the manufacturer thus reducing the need for voice radio exchanges.

In addition, the AIS enhances the mariner's situational awareness, permits more effective and reliable passing arrangements, and provides the Coast Guard with a comprehensive and informative traffic image and maritime domain awareness not possible with radar or video surveillance alone.

The Coast Guard believes that the AIS will improve security by increasing the Coast Guard's awareness of vessels in the maritime domain, especially vessels approaching U.S. ports. The AIS corroborates and provides identification and position of vessels not always possible through voice radio communication or radar alone.

An approved AIS can range in price between $2500 and $5000, not including installation cost which will vary considerably depending on the level of integration of the AIS with other shipboard systems (e.g. radar, speed log, rate of turn indicator, navigation positioning system, ECDIS, etc.)

In addition to radar, AIS has the following benefits:

• Automatic and immediate vessel identification
• Improved vessel tracking (no track swap)
• Wider geographical coverage
• Greater positional accuracy
• Absence of radar shadow area
• Real time manoeuvring data

Other than a power loss the proper operation and information validity requires a verification from another AIS station.

AIS is mainly for monitoring other ships and allows only the transmission of safety related messages on AIS designated frequencies.

Yes, ACR offers training on demand with certificates for participants.

The Flash Equipment for the ACR Nauticast (X-Pack DS) consists of:

• CD-ROM Software
• Flasher Documentation
• Flash-Cable (24V/DC power connector and RS232 Interface cable to the PC)

If you don't have this Flash Equipment available, please contact Technical Support at:

ACR Electronics Europe GmbH
Handelskai 388 / Top 632
A-1070 Vienna, Austria

T:     0043-1-5 237 237-240
F:     0043-1-5 237 237-150
M:    technical.support@acr-europe.com
W:    www.acr-europe.com

Before you start the flash process ensure that you have the latest software available (refer to the reseller section at www.acr-europe.com)

The GPS connected to the AIS must fulfill the IMO performance standard.  It means inter alia that the output from the GPS must be in WGS 84 and that there is no dead reckoning of the position.