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The TouchDownLiftOff class is used for defining a load bearing area on which a helicopter may touch down or lift-off.
A TLOF may be situated on an Runway (of type equal-to 'FATO') or directly at an AirportHeliport. (i.e. The TLOF may form an integral part of the FATO or be situated apart at an airport/heliport or may be even offshore).
A TLOF is identified by its designator.
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