How is the TLOF surface floodlit?
Floodlights set outside the touchdown area, aimed across it so the surface and its markings can be seen.
TLOF floodlighting lights the surface itself, not just its edge. Floodlights set outside the touchdown and lift-off area wash light over the surface so the pilot can judge it and see the H marking and any other markings or obstacles on it.
ICAO Annex 14 Volume II recommends an average horizontal illuminance of at least 10 lux on the TLOF surface, with a uniformity ratio (average to minimum) of not more than 8:1. The lights are placed and aimed to keep shadows to a minimum and to avoid glare to a pilot in flight or to people on the TLOF. Their spectrum must let the surface and obstacle markings be identified correctly.
Light the surface and its markings so the area can be seen and judged.
Mark the edge of the touchdown surface with green points of light. See Entry 2.
Frequently Asked Questions
Q1What is TLOF floodlighting?
Floodlights that light the touchdown and lift-off area (TLOF) surface itself, rather than just marking its edge. They let the pilot see the surface, the H marking and any painted or physical markings and obstacles on it.
Q2How is it different from TLOF perimeter lighting?
Perimeter lights are points of green light that show where the edge of the surface is. Floodlights wash white light over the surface so the pilot can judge it and see the markings. They can be used together, and Entry 2 covers the perimeter lights.
Q3How much light should the surface get?
ICAO Annex 14 Volume II recommends an average horizontal illuminance of at least 10 lux, measured on the TLOF surface, with a uniformity ratio (average to minimum) of not more than 8:1. National regulators may set their own values, so confirm against the standard in force.
Q4Where are the floodlights placed and aimed?
Outside the TLOF, normally from more than one side, and aimed across the surface so the beams overlap. They are positioned and aimed so that shadows are kept to a minimum and so that they do not dazzle a pilot in flight or people working on the TLOF. Their height and position are also limited by the heliport’s obstacle limitation surfaces and safety area.
Q5Why does the light spectrum matter?
The spectral distribution of the floodlights must let the surface markings and any obstacle marking be identified correctly. A light that shifts colours can make a marking look like a different one, so the lamp or LED type is chosen with this in mind.
Q6Which standards apply?
ICAO Annex 14 Volume II covers heliports, and national regulators publish their own requirements, such as the FAA heliport design advisory circular. Which lighting is required at a given heliport, and the figures, can differ between them, so confirm against the standard in force and the project specification.
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