In accordance with CAP 437 a visual warning system should be installed on a helideck if a condition can exist which may be hazardous for the helicopter or its occupants. For example this could be due to gas detection or the use of a crane in the vicinity of the helideck.
The system may comprise one or two main status lights each with a red LED flasher for long life (80,000 hours) and low maintenance housed in an Exd well glass enclosure. Repeater lights are also available so that a helicopter already on the helideck will be able to see a red light at any angle or degree of azimuth. The system has a small Exd control panel and is capable of both automatic operation (input from a fire and gas system) and manual activation by the helideck landing officer.
The main light can also be dimmed in intensity while the helicopter is landed on the helideck.
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