Touchdown Zone Elevation
|Term||Touchdown Zone Elevation|
The value of the highest elevation of the runway Touchdown Zone (TDZ).
The Touchdown zone is the portion of a runway, beyond the threshold, intended as the first point of contact between landing aircraft and the runway. 1. For fixed wing aircraft the touchdown zone extends from the threshold for a longitudinal distance of 900 metres, except that on runways less than 1800 metres in length, the touchdown zone shall be shortened so that it does not extend beyond the midpoint of the runway. 2. For rotary-wing and vectored-thrust aircraft, the portion of the helipad or runway used for landing.