How is the FATO perimeter lit?
A ring of omnidirectional lights, white under ICAO and green under FAA, on the edge of the final approach and take-off area, with a light at every corner.
The final approach and take-off area (FATO) is the area over which a helicopter completes its approach and begins its take-off. At night its edge is shown by fixed omnidirectional lights placed along the boundary, so the pilot can see where the area ends from any direction. ICAO Annex 14 Volume II specifies white FATO lights; FAA practice uses green. The TLOF perimeter lights inside it are green in both (Entry 2).
On a square or rectangular FATO there are at least four lights along each side, including one at each corner, spaced evenly at not more than 50 m at a surface-level heliport. A circular FATO has at least ten lights, spaced not more than 5 m apart. At an elevated heliport or helideck the FATO normally coincides with the TLOF, so the green TLOF perimeter lights (not more than 3 m apart, Entry 2) mark the edge. The lights are kept low and frangible, or inset, because of rotor downwash and the need to keep the area clear of obstacles.
Mark the edge of the larger area for approach and take-off.
Mark the load-bearing touchdown area inside it. See Entry 2.
Frequently Asked Questions
Q1What is FATO perimeter lighting?
Fixed omnidirectional lights placed along the edge of the final approach and take-off area (FATO) so a pilot can see the boundary of the area at night or in poor visibility. They show the pilot where the area ends, not where to touch down.
Q2What is the difference between the FATO and the TLOF?
The FATO is the larger area over which the approach is completed and the take-off begins. The TLOF is the load-bearing area inside it where the helicopter touches down and lifts off. Each has its own perimeter lights; the TLOF lights are covered in Entry 2.
Q3What colour and type are FATO perimeter lights?
Under ICAO Annex 14 Volume II they are fixed, omnidirectional lights showing white, so the boundary is visible from any direction of approach. FAA practice uses green. The TLOF perimeter lights are green in both. A national regulator may add detail, such as intensity or night-vision-goggle compatibility, so check the standard in force.
Q4How far apart are the lights?
For a rectangular FATO at a surface-level heliport, ICAO Annex 14 Volume II calls for at least four lights along each side, including one at each corner, spaced not more than 50 m apart. A circular FATO has at least ten lights, not more than 5 m apart. At an elevated heliport or helideck the FATO normally coincides with the TLOF, whose perimeter lights are not more than 3 m apart. Confirm against the edition in force.
Q5Why are FATO lights kept low?
Rotor downwash and the need to keep the area free of obstacles limit how high a light can stand. The lights are kept low and frangible, or inset where the design requires it, and must not become a hazard to a helicopter that touches or rolls over them.
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 in the United States. Spacing, light type and height differ between them, so confirm the figures against the standard in force and the project specification.
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