5.2.5 Heading indication
5.2.5.1 When inside the field of view, the heading of the craft should be indicated by a marker at the top of the display with a maximum error not greater than +/- 1 degree.
5.2.5.2 A visual indication should be provided when the heading marker is outside the field of view.
5.2.6 Roll or pitch
The performance of the NVEE should be such that when the craft is rolling and pitching up to +/- 10 degrees the performance requirements in this standard should be complied with.
5.2.7 Clear view
Arrangement should be provided to ensure efficient cleaning of the sensor head/lens regardless of weather condition.
5.2.8 Interference
The performance of the NVEE should not be unduly affected by any dazzle effects, reflections, blooming, or any other related phenomena.
5.3 Malfunctions, alarm and indications
NVEE should have the following displays;
.1 state of operation; and
.2 alarm in the event or failure of the NVEE.
5.4 Software requirements
To conform to IMO A.694(17) and applicable IEC requirements*.
6 ERGONOMIC CRITERIA
6.1 Operational controls
The number of operational controls should be limited to the minimum required for operation.Double functions of operational controls should be avoided.
The functions of the individual operational controls should be clearly labelled.
The functions of NVEE should be activated directly through the operational controls; menu-driven controls should be avoided.
*IEC 945.
