IMO-SUB-COMMITTEEE ON SAFETY OF NAVIGATION
44th SESSION
MATTERS CONCERNING THE TRANSMISSION OF SHIP TRUE HEADING
TECHNICAL WORKING GROUP-AGENDA ITEM 7
CONTRIBUTION TO THE CHAIRMAN'S REPORT
Various papers were input to this session on this subject with the aim of deftining performance standards for equipments that require true heading inputs.
At this time IMO has defined the performance standards for magnetic and gyro compasses. In the latter case for both conventional and high speed craft.
There are certain equipments within SOLAS Chaptervand SOLAS ChapterXthat may require a true heading input that requires inputs from devices that have characteristics that lie between those specified for the present magnetic and gyro compasses.
With this in mind the Technical Working Group have amended the draft performance standards for electromagnetic compasses to reflect the characteristics of other types of magnetic compasses under the generic title of "transmitting magnetic heading devices (TMHD)"
In principle such devices should have accuracy and operational characteristics that have advantages for transmission of heading information to equipments between those that clearly require the characteristics of either a standard magnetic or gyro compass.
To justify these amended characteristics (TMHD), the IMO SOLAS Convention Chapter v and X (for high speed craft) have been examined in detail, together with the relevant IMO performance standards to summarise the IMO requirements for true heading information.
These are summarised in Annex A, and the amended performance standards for TMHD are in Annex B.
