18.1 Compass
18.1.1 A vessel should be fitted with an efficient magnetic compass, or other means
independent of the main power supply, for determining and displaying heading, as well as
means of correcting heading and bearings to true at all times (e.g. a valid deviation
card). Magnetic compasses should be properly adjusted and in a steel vessel it should be
possible to correct a magnetic compass for coefficients B, C and D and heeling error.
18.1.2 Each magnetic compass should be properly adjusted and its deviation card
available at all times. Magnetic compasses should be adjusted when:
- .1 they are first installed;
- .2 they become unreliable;
- .3 the vessel undergoes structural repairs or alterations that could affect its
permanent and induced magnetism;
- .4 electrical or magnetic equipment close to the compass is added, removed or
altered; or
- .5 a period of two years has elapsed since the last adjustment and a record of
actual compass deviations has not been maintained, or the recorded deviations are
excessive or when the compass shows physical defects.
It is strongly recommended that a ‘Compass Error’ record is maintained with regular
compass errors taken and fully recorded as a proper record of the compass’ reliability
where the compass is not swung in accordance with the requirements.
18.1.3 Vessels operating in Area Category 6 need not comply with the requirements of
18.1.1, and 18.1.2 provided that a suitable marine magnetic compass with consistent
deviation is carried on board, installed at the main steering position. For the purposes
of this paragraph ‘consistent deviation’ is considered to be when there has been no
appreciable change observed within the two years preceding the date of inspection by the
Master.
18.1.4 The compass, alternative device or a repeater:
- .1 should be clearly readable at all times at the main steering position
(including a light where by reason of operations in darkness or low natural light);
and
- .2 means should be provided for taking bearings as nearly as
practicable over an arc of the horizon of 360 degrees. (This requirement may be met
by a pelorus or, in a vessel other than a steel vessel, a hand bearing compass).
18.2 Transmitting Magnetic Heading Device (TMHD)footnote
18.2.1 A TMHD is acceptable as an alternative to the magnetic compass required in
18.1.1, 18.1.2 and 18.1.3, provided that a suitable back-up power supply is available to
power the equipment in the event of failure of the main electrical supply.
18.2.2 Where a TMHD incorporates a capability to measure magnetic deviation by
undertaking a calibration routine, and where the deviation figures are recorded and
adequately compensated for within the device, a deviation card is not required.
18.3 Echo Sounder
18.3.1 All vessels should be fitted with an echo sounder, or other effective means to
measure the available depth of water.
18.4 Other Navigational Equipment for vessels that are Certified to operate more than
20 miles from land (Area Category 0, 1 or 2)
18.4.1 An Electronic Position Fixing System that may be a global navigation satellite
system (e.g. GPS) or a terrestrial radio-navigation system, or other means suitable for
use at all times throughout the voyage to establish and update the vessel’s position by
automatic means.
18.4.2 A distance measuring log; except that this need not be provided where the
navigational aid in section 18.4.1 provides reliable distance measurements in the area
of operation of the vessel.
18.4.3 Consideration should be given to fitting a suitable Class "A" Automatic
Identification System (AIS) transceiver to vessels that operate in areas that use AIS as
part of the area safety management. Owners / managing agents should undertake AIS
testing, if fitted, in accordance with the guidance in MGN 465footnote Annex 2. See also section 25.9.4.
18.4.4 A 3 cm Radar, complying with EN 62252footnote (Class A standard), EN 302 248 and the R&TTE
Directivefootnote should be fitted, except that radars for vessels designed
to operate at speeds over 30 knots are to comply with the MED. Where radar is equipped
with automatic target tracking then a suitable transmitting heading device shall be
fitted.
18.4.5 Additionally, vessels that are operated at high speed are recommended to be
provided with an electronic chart system to satisfy chart carriage requirements as in
19.1, complying at least with the specifications required by the SeaFish Industry
Authority (SFIA), see also section 19.1.2 and MGN 319.
18.5 Electronic aids to navigation should be routinely tested and well maintained
in accordance with the manufacturer’s instructions.