(Photograph courtesy of John Burt Associates Limited)
Powered by a fluorescent luminaire they offered designers (in the early years of offshore helideck designs) a compact helideck lighting solution. However, the extent of the beam cast by the floodlighting is very limited and will invariably give a ‘black hole’ effect.
Combined perimeter and floodlights do not meet the current ICAO uniformity and intensity ratio requirements and are therefore unacceptable and should no longer be specified. When re-working or modifying a helideck they should be replaced or supplemented by lighting units complying with the appropriate ICAO specification.
11.3.5.4 Floodlighting on Vessel Helidecks
Floodlighting units are available with an IP Rating suitable for immersion in seawater. However, the fixings need to be very robust to withstand damage.
In this case it may be considered prudent to locate some helideck floodlighting units at a higher elevation to protect them (e.g. on or under the bridge apron).
If this arrangement is to be considered acceptable, the designer must be able to demonstrate to the BHAB Helidecks that the lighting will be able to cover the safe landing area without creating night vision ‘dazzle’ problems for the flight crews. The positioning (direction) of the lighting units should also be fully adjustable and there should be proper provision (e.g. shutters or a deflector) to prevent unwanted light overspill above the units.
11.3.5.5 Power Supply and Control
Similar to perimeter lights, there is considerable merit in designing the supply system for floodlighting to operate from two separate power circuits. Alternate lights should be supplied from different power supplies. This has the effect of at least providing half the floodlighting if there is a circuit malfunction in one of the electrical supplies.
11.3.6 General Lighting
11.3.6.1 Objective
The objective of installing general lighting on offshore installations and vessels and their helidecks is to provide a safe work environment for personnel, helideck crews and for passenger movements at night and in low light conditions.
However, providing this general installation and helideck lighting can present a flight safety problem.
Therefore, the design, location and maintenance of general lighting requires great care in order that flight crew night vision is not affected and the helideck visual cues are not compromised.
11.3.6.2 Equipment Specification & Layout
General Installation / Vessel
The selection of Installation general lighting is normally carried out as a separate exercise to the helideck design. This will generally mean that selection and location of lighting units will simply take into account the need to illuminate the installation’s external walkways, stairways, work platforms, production and drilling areas, etc. It is important that the helideck designer influences the manner in which the layout of general lighting proceeds. Ideally, general lighting units, particularly floodlights, should be positioned and directed so that they cast their light INTO the installation thus avoiding unnecessary ‘overspill’ that may pollute potential flight paths and the helideck.
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