12 System failures and fallback arrangement
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Statutory Documents - IMO Publications and Documents - Resolutions - Maritime Safety Committee - Resolution MSC.252(83) - Adoption of the Revised Performance Standards for Integrated Navigation Systems (INS) - (Adopted on 8 October 2007) - Annex - Performance Standards for Integrated Navigation Systems (INS) - Module B - Task related requirements for Integrated Navigation Systems - 12 System failures and fallback arrangement

12 System failures and fallback arrangement

  12.1 The INS should, after a failure, and when the back-up activation is not successful support the availability of essential information and functions through the use of appropriate fallback arrangements (see 12.7).

  12.5 The automatic response to malfunctions should result in the safest possible configuration accompanied by an alert.

Parent topic: Module B - Task related requirements for Integrated Navigation Systems

12.2 Restored operation

 Normal operation, after use of a fallback arrangement, should only be restored upon confirmation by the operator.

12.3 Failure or change of sensor

  12.3.1 The failure or change of a sensor should not result in sudden changes of control commands or loss of manoeuvring control. This may be accomplished by appropriate integrity checks using the information from several sources.

  12.3.2 In case of a sensor or source failure, the system should provide an alert and indicate (an) alternative sensor(s) or source(s), as available.

  12.3.3 If sensors or sources are not able to provide necessary ship status or navigation data for automatic control functions, a dead reckoning procedure should provide the missing information, as far as practicable.

12.4 Storage of system related parameters

 All system related parameters and settings should be stored in a protected way for reconfiguration of the INS.

12.6 Alert management

  12.6.1 System failures should be alerted according to the requirements described in Module C.

  12.6.2 Loss of system communication between the alert management and the navigational systems and sensors should be indicated as a warning at the central alert management HMI.

  12.6.3 A system failure of the alert management or the loss of system communication between the alert management and the navigational functions, sources and/or sensors, should not lead to the loss of the alert announcement functionality of the individual navigational functions, sources/sensors.

12.7 Fallback for navigational information failure

  12.7.1 In the event of failures of navigational information and to maintain minimum basic operation,

  • there should be a permanent indication of the failed input information and the fall- back activated,
  • the respective actions of the alert management should be activated, and
  • the fallback arrangements listed below should be provided.

  12.7.2 Route monitoring

  12.7.2.1 Failure of heading information (Azimuth Stabilization)

 The INS should display own ship's position and over-ground-motion vector in the chart and not the ship's heading line.

  12.7.2.2 Failure of course and speed over ground information

 The INS should display own ship's position and heading line.

  12.7.3 Collision avoidance

 In the case of failure of:

  • Heading information
  • Speed through the water information
  • Course and speed over ground information
  • Position input information
  • Radar video input information
  • AIS input information,

 the INS should operate as defined in the operational Module B4 of the proposed modular structure for radar performance standards as set out in appendix 3.

  12.7.4 Heading/Track control

 The requirements for the applicable control function as specified in the individual performance standards should apply.

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