What is defined as absolute altitude?

Absolute altitude is defined as the height of the aircraft above the surrounding terrain. This measurement provides important information for pilots as it indicates how high the aircraft is flying relative to the ground directly beneath it.

The focus here is on understanding that absolute altitude takes into account the elevation of the terrain and varies depending on the landscape. For instance, when flying over mountains, the absolute altitude would be different than when flying over flat plains, even if the aircraft is at the same indicated altitude. This measurement is crucial during landing, takeoff, and maneuvering in proximity to ground obstacles.

In contrast, height above sea level is referred to as pressure altitude or elevation and does not provide information about how high the aircraft is relative to the ground features. Therefore, understanding the context of altitude measurements is vital for safe aviation practices.