Touchdown and Lift off | LTOF | ZA295L

A heliport can consist of several applications to aid the safe landing and take-off of aircraft.

One of the applications is a touchdown and lift-off area (TLOF) which can be surrounded by a final approach and take-off area (FATO). Generally, a safety area is provided around the FATO. The relationship of the TLOF to the FATO and the Safety Area can be found in several CAA/FAA publications.

The size of a TLOF is dependant on the type of helicopter using the pad. Commonly, the TLOF should be square or rectangular in shape and the minimum length should be the rotor diameter but suggested not less than 15 meters.

From a lighting perspective, Green lights should be used to define the TLOF perimeter, with a minimum of 4 lights fixtures per side of the square or rectangle. This includes a light being installed at each corner. The lights along each edge should be uniformly spaced but the distance between each fixture should not exceed 5 metres for surface level heliports. For elevated heliports, the distance is reduced to a maximum distance between fixtures of 3 metres.

The ZA295 or ZA295(L) is designed to be used for this application. The fixture can be powered by the use of a constant current regulator (CCR) the same type used for airfield lighting. However, it is more common to see helipads powered by 230/120 volts AC. This option simplifies and the supply voltage required is available from the local power infrastructure. Should there be a requirement for the fixtures to be powered from a 24vDC supply this option is available upon request.

The ZA295 employs a tungsten halogen lamp with a green dichroic filter to provide the required light and colour output. Alternatively, the ZA295(L) uses an internal electronics package which provides a regulated supply to light emitting diodes (LEDs) which are green in colour.

The E-FATO fixture should be used if an elevated option is required for this application. This fixture is mounted on a central stem with frangible coupling and is powered by 120/230v AC

Applications:

• Omni-directional Inset fitting for touchdown and lift off area (TLOF)
• A TLOF lighting system shall be provided at a heliport
• intended for use at night. 
• The TLOF lighting system for a surface-level heliport shall consist of one or more of the following:
  • perimeter lights
  • floodlighting
  • arrays of segmented point source lighting (ASPSL) or  luminescent panel (LP) lighting to identify the TLOF when a)  and b) are not practicable and FATO lights are available.

• The TLOF lighting system for an elevated heliport or helideck shall consist of 
  • perimeter lights; and 
  • ASPSL and/or LPs to identify the touchdown marking  where it is provided and/or floodlighting to illuminate the TLOF.