Chapter 12 - Navigational equipment
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Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC/Circular.1056 – Guidelines for Ships Operating in Arctic Ice-Covered Waters – (Adopted on 23 December 2002) - Annex - Guidelines for Ships Operating in Arctic Ice-Covered Waters - Part B - Equipment - Chapter 12 - Navigational equipment

Chapter 12 - Navigational equipment

12.1 Application

 It should be noted that the provisions prescribed in this chapter are not to be considered in addition to the requirements of SOLAS chapter V. Rather, any equipment fitted or carried in compliance with the requirements of SOLAS chapter V may be considered as part of the recommended equipment complement detailed in this chapter. Unless specifically provided in this chapter, the performance standards and other applicable guidance for equipment and systems contained in this chapter should be applied mutatis mutandis as per SOLAS chapter V.

12.2 Compasses

  12.2.1 Magnetic variations in high latitudes may lead to unreliable readings from magnetic compasses.

  12.2.2 Gyro-compasses may become unstable in high latitudes and may need to be shut down.

  12.2.3 Companies should ensure that their systems for providing reference headings are suitable for their intended areas and modes of operation, and that due consideration has been given to the potential effects noted in paragraphs 12.2.1 and 12.2.2. For operations in Arctic ice-covered waters, ships should be fitted with a total of at least two gyro-compasses.

12.3 Speed and distance measurement

  12.3.1 All Polar Class ships should be fitted with a total of at least two speed and distance measuring devicesfootnote. Each device should operate on a different principle, and at least one device should be capable of being operated in both the sea and the ground stabilized mode.

  12.3.2 Speed and distance measuring devices should provide each conning position with a speed indication at least once per second.

  12.3.3 Speed and distance measurement device sensors should not project beyond the hull and should be installed to protect them from damage by ice.

12.4 Depth sounding device

 All Polar Class ships should be fitted with a total of at least two independent echo-sounding devices which provide indication of the depth of water under the keel. Due account should be taken of the potential for ice interference or damage to any device designed to operate below the waterline.

12.5 Radar installations

  12.5.1 All Polar Class ships should be fitted with a total of at least two functionally independent radar systems. One of these should operate in the 3 GHz (10 cm, S-band) frequency range.

  12.5.2 Radar plotting systems that may be installed should have the capability of operating in both the sea and the ground stabilized mode.

12.6 Electronic positioning and electronic chart systems

  12.6.1 All Polar Class ships should be provided with an electronic position fixing system.

  12.6.2 A satellite system (GPS or GLONASS or equivalent) should be fitted on any ship intending to navigate in areas outside of reliable coverage by a terrestrial hyperbolic system.

  12.6.3 Systems described in paragraphs 12.6.1 and 12.6.2 should provide input to allow for continuous representation of the ship's speed provided by a speed and distance measuring device according to paragraph 12.3, and the ship's course provided by a compass according to paragraph 12.2footnote.

  12.6.4 Where fitted, electronic charting systems should be able to use position input from systems compliant with paragraphs 12.6.1 and 12.6.2.

12.7 Automatic identification system (AIS)

 All Polar Class ships should be provided with and automatic identification system (AIS)footnote for ships using the broadcast mode.

12.8 Rudder angle indicator

  12.8.1 Separate rudder angle indicators should be provided for each rudder on ships with more than one rudder.

  12.8.2 In ships without a rudder, indication should be given of the direction of steering thrust.

12.9 Searchlights and visual signals

  12.9.1 Ships of Polar Classes 1 to 5 inclusive and all ships intended to operate in periods of prolonged darkness should be equipped with at least two suitable searchlights which should be controllable from conning positions.

  12.9.2 The searchlights described in paragraph 12.9.1 should be installed to provide, as far as is practicable, all-round illumination suitable for docking, astern manoeuvres or emergency towing.

  12.9.3 The searchlights described in paragraph 12.9.1 should be fitted with an adequate means of de-icing to ensure proper directional movement.

  12.9.4 Ships of Polar Classes 1 to 5 inclusive, all icebreakers and all ships that may be involved in an escort of more than one ship following in an ice track should be equipped with a manually operated flashing red light visible from astern to indicate when the ship is stopped. This should be capable of use from any location from which the ship can be manoeuvred. The flashing light should have a range of visibility of at least two (2) nautical miles. The colour and frequency of the flashing light should be according to standards given in COLREG. The horizontal and vertical arcs of visibility of the flashing light should be as specified for stern lights in COLREG.

12.10 Vision enhancement equipment

  12.10.1 All Polar Class ships should be fitted with a suitable means to de-ice sufficient conning position windows to provide unimpaired forward and astern vision from conning positions.

  12.10.2 The windows described in paragraph 12.10.1 should be fitted with an efficient means of clearing melted ice, freezing rain, snow, mist and spray from outside and accumulated condensation from inside. A mechanical means to clear moisture from the outside face of a window should have operating mechanisms protected from freezing or the accumulation of ice that would impair effective operation.

  12.10.3 All persons engaged in navigating the ship should be provided with adequate protection from direct and reflected glare from the sun.

  12.10.4 All indicators providing information to the conning positions should be fitted with means of illumination control to ensure readability under all operating conditions.

12.11 Voyage data recorder

 Ships of Polar Classes 1 to 5 inclusive should be fitted with a voyage data recorderfootnote.

12.12 Ice routing equipment

  12.12.1 All ships should be provided with equipment capable of receiving ice and weather information charts.

  12.12.2 Ships of Polar Classes 1 to 3 inclusive should be fitted with equipment capable of receiving and displaying ice imagery.


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