5 Information to be provided when requesting LRIT information

  5.1 A SAR service, when wishing to receive LRIT information should indicate to the LRIT Data Centre the criteria to be used by the centre when providing the requested information.

  5.2.1 For the purposes of regulation V/19-1.12 (i.e. for the search and rescue of persons in distress at sea), the criteria to be provided, subject to the provisions of paragraphs 5.3 to 5.4.2, are:

• .1 the geographical area within which LRIT information is requested; and

• .2 the number of LRIT information transmissions requested.

  5.2.2 For the purposes of paragraph 1.3 (i.e. when an uncertainty or alert phase might need to be declared or has been declared in relation to a specific ship and there is a need to ascertain its whereabouts) the criteria to be provided, subject to the provisions of paragraphs 5.3 and 5.5.1 to 5.5.3, are:

• .1 the name of the ship in question;

• .2 the IMO ship identification number of the ship;

• .3 the Contracting Government whose flag the ship is entitled to fly;

• .4 the nature of the LRIT information requested (i.e. the provision of the most recent LRIT information; the polling or on on-demand transmission of LRIT information; or the provision of archived LRIT information transmitted by the ship during a specified period together with the dates and times between which the information is requested).

  5.3 All LRIT Data Centres are required to provide to SAR services LRIT information irrespective of the location of the geographical area within which the information is requested. Thus, SAR services are able to request LRIT information for geographical areas which are located outside the search and rescue regions which are under their responsibility.

  5.3.1 The geographical area may be either circular or rectangular and for these the Technical specifications for communications within the LRIT system use the terms SAR circular area and SAR rectangular area, respectively. SAR services are advised to take into account the information provided in paragraphs 5.4 to 5.4.2 below when defining the geographical areas within which they are requesting the provision of LRIT information. In addition, SAR services, when formulating their initial request for the provisions of LRIT information, are advised to define the geographical area within which they are requesting the provision of LRIT information in a manner that is larger than the search area they have identified for search and rescue purposes, so as to be able to easily identify which ships are transiting towards or away from the specific location.

  5.3.2 When requesting LRIT information within a SAR circular area the geographical position of the centre of the area should be indicated in latitude and longitude and the radius in nautical miles. The radius of the SAR circular area should not exceed 999 nautical miles. Any requests which include a radius in excess of 999 nautical miles would be rejected by the LRIT Data Centres which are asked to process them.

  5.3.3 When requesting LRIT information within a SAR rectangular area the geographical position of the Southwest corner of the area should be indicated in latitude and longitude and the North and East offsets in degrees and minutes. Each offset should not exceed 2,000 nautical miles. Any requests which include an offset in excess of 2,000 nautical miles would be rejected by the LRIT Data Centres which are asked to process them.

  5.3.4 The LRIT system operates using WGS 84 datum and thus all geographical positions should be with reference to the WGS 84 datum.

  5.3.5 All geographical positions (latitude and longitude) should be in degrees and minutes, with a single space between the coordinates and no other spaces, without punctuation, with leading zeros for single number minutes, but not for degrees and with the minutes tick following the minutes part, for example 51°42' N 5°07' E.

  5.4 The number of LRIT information transmissions requested relates to the LRIT information received within the LRIT system during the 24 hours preceding the time the LRIT Data Centre will lodge the request of the SAR service for LRIT information and for these the Technical specifications for communications within the LRIT system use the term number of position reports. In this respect, it should be noted that, unless there is a demand for the transmission of LRIT information at more frequent intervals, the shipborne equipment are preset to transmit LRIT information at 6-hour intervals.

  5.4.1 When a SAR service indicates a value of 2 in relation to the number of positions it is requesting, it will receive the last two LRIT information transmissions from all ships within the defined geographical area during the previous 24 hours.

  5.4.2 SAR services are advised to indicate to the LRIT Data Centre the number of positions they are requesting as it will provide them information in relation to the direction the various ships are heading. However, the number of positions to be requested should not exceed 4.

  5.5.1 When requesting the provision of the most recent LRIT information transmitted by the ship in question, the LRIT Data Centre serving the SAR service will lodge the request and the LRIT Data Centre to which the ship was instructed to transmit LRIT information will provide the LRIT information it received from the ship immediately before the time the request was lodged. For these the Technical specifications for communications within the LRIT system use the term most recent position report. In this respect, it should be noted that, unless there is a demand for the transmission of LRIT information at more frequent intervals, the shipborne equipment are preset to transmit LRIT information at 6-hour intervals. In addition, it should be noted that, in case the last available transmission of LRIT information from the ship in question occurred more than 6 hours prior to the time the request was lodged, the LRIT information may need to be retrieved from the archives of the LRIT Data Centre to which the ship was instructed to transmit LRIT information.

  5.5.2 When requesting the polling or on-demand transmission of LRIT information from the ship in question, the LRIT Data Centre serving the SAR service will lodge the request and the LRIT Data Centre to which the ship has been instructed to transmit LRIT information will transmit to the ship the relevant commands and await its response. For these the Technical specifications for communications within the LRIT system use the term one time poll of ship. In this respect, it should be noted that the Revised performance standards stipulate that on-demand LRIT information should be provided to an LRIT Data User (i.e. in the case the SAR service requesting the information) within 30 min of the time the LRIT Data User requested the information.

  5.5.3 When requesting the provision of archived LRIT information transmitted during a specified period by the ship in question, the LRIT Data Centre serving the SAR service will lodge the request specifying the dates and times between which the information is requested and the LRIT Data Centre to which the ship was instructed to transmit LRIT information will retrieve the archived LRIT information transmitted by the ship during the time frame specified in the request it received. For these the Technical specifications for communications within the LRIT system use the term archived LRIT information request. In this respect, it should be noted that the Revised performance standards stipulate that for LRIT information archived within the last 4 days these should be sent to the requestor within 30 min of receiving the request; if archived between 4 and 30 days previously within 1 h of receiving the request; and if archived more than 30 days previously within 5 days of receiving the request.