18 NAVIGATIONAL EQUIPMENT AND VISIBILITY FROM WHEELHOUSE
18.1 Navigational Equipment
18.1.1 A vessel should be fitted with the following:-
.1 A properly adjusted standard magnetic compass or other means, independent of any power supply to determine the ship's heading.
.2 In a steel vessel, it should be possible to correct the compass for co-efficients, B, C and D and heeling error
.3 The magnetic compass or a repeater should be so positioned as to be clearly readable by the helmsman at the main steering position. It should also be provided with an electric light, the electric power supply to be twin wire type.
18.1.2 A vessel should be fitted with, the following additional equipment:
.1 an echo sounder.
.2 a receiver for a global navigation satellite system or a terrestrial radio-navigation system, or other means suitable for use at all times throughout the intended voyage to establish and update the ship's position by automatic means;
.3 a distance measuring log;
.4 a gyro compass or spare magnetic compass bowl;
.5 a rudder angle indicator; and
.6 a 9 GHz radar.
18.1.3 For vessels of less than 300gt the equipment specified in 18.1.1 and 18.1.2 need not be of an approved type.
18.1.4 Means should be provided for taking bearings as near as practicable over an arc of the horizon of 360 o . This requirement may be met by the fitting of a pelorus compass, or, on a vessel other than a steel vessel, with a hand bearing compass.
18.1.5 For vessels under 300gt the requirements of 18.1.2.4 may be met by the use of a fluxgate compass, provided that a suitable back up power supply is available to power the compass in the event of failure of the main electrical supply. Where such a compass incorporates a capability to measure, magnetic deviation by undertaking a calibration routine, and where the deviation figures are recorded within the device, a deviation card is not required.
18.1.6 Attention should be paid to magnetic effects on magnetic compasses, including fluxgate compasses, when operating in Polar Regions. (i.e. north of 70° N, or south of 70° S).
18.1.7 All vessels of 300gt and over shall be fitted with an approved automatic identification system (AIS) in accordance with SOLAS Chapter V, no later than the end of December 2004. The AIS shall:
.1 provide automatically to appropriately equipped shore stations, other ships and aircraft information, including the ships id, type, position, course, speed, navigational status and other safety related info;
.2 receive automatically such info from similarly fitted ships
.3 monitor and track ships; and
.4 exchange data with shore based facilities.
18.2 Bridge Visibility
18.2.1 Navigation bridge visibility should comply with SOLAS Chapter V. Vessels under 45m in length should comply as far as reasonable and practicable
18.2.2 Windows may be inclined from the vertical plane provided that, where necessary, appropriate measures are taken to avoid adverse reflections from within.
18.2.3 Windows to the navigating position should not be of either polarised or tinted glass (see 5.5.5) Portable tinted screens may be provided for selected windows.