Which environmental factor is NOT considered in the landing distance calculation?

In the context of landing distance calculations, visibility is not a factor that directly affects the physical distance required for landing an aircraft. Landing distance is primarily influenced by environmental factors that impact the aircraft's performance and the aerodynamic conditions during the landing phase.

Temperature affects air density, which in turn impacts engine performance and lift, as well as drag on the aircraft. Higher temperatures can lead to decreased performance, requiring a longer distance to land.

Pressure altitude is crucial because it determines the density of the air. At higher pressure altitudes, the air is less dense, which means the aircraft generates less lift and engine performance may be reduced, also resulting in longer landing distances.

The wind component, especially the crosswind and headwind, plays a significant role in landing performance. A headwind can reduce the distance required for landing, while a tailwind can increase the landing distance, due to the change in approach speed and ground speed at touchdown.

Considering these factors, visibility does not affect the physical landing distance in the same way; rather, it impacts flight safety and the ability to see the runway or obstacles but does not necessitate a change in performance calculations regarding distance.