New AIS advice from EUNAVFOR and NATO [citing IMO Resolution A.917(22)] states “the Master has the discretion to switch off the AIS if he believes its use increases the ship’s vulnerability”.
Until now it has been recommended that AIS transmission within the Gulf of Aden be left on with restrictions, and outside the Gulf of Aden in other parts of the High Risk Area be turned off completely.
The NEW recommendation is to leave AIS transmitting across the entire High Risk Area as set out in BMP3. AIS transmission should continue to be restricted to ship’s identity, position, course, speed, navigational status and safety-related information. As noted, this is a change to the previous guidance which recommended that AIS be left on only in the Gulf of Aden. The decision on AIS policy remains at the discretion of the Master, however, if it is switched off during transit, it should be activated immediately at the time of an attack.