13.3.1 One compass suitable for the craft and
the intended area of service should be provided together with such
repeaters as may be necessary.
13.3.2 Where such a compass is operated by mechanical
and electrical means, a suitable stand-by direct reading magnetic
compass should be provided.
13.3.3 The compass card or repeater should be
capable of being easily read from the position at which the craft
is normally controlled.
13.3.4 A table of deviations should be provided
for each magnetic compass and this should be checked annually, or
whenever structural alterations or events have occurred which may
cause large deviations.
13.3.5 Care should be taken in siting the compass
or sensing element so that magnetic interference is eliminated or
minimized as much as is practicable.
13.3.6 Where intermittent operation of other instruments
affects the compass, notice of the crew should be drawn to the magnitude
and sense of the deviations so caused.