What is a common error associated with NDB navigation due to high terrain?

In NDB (Non-Directional Beacon) navigation, high terrain can significantly affect the accuracy of the signals being received by the aircraft. This phenomenon is known as Terrain Error. When an aircraft is navigating by reference to an NDB, it relies on receiving radio signals emitted from the NDB to determine its position and direction. However, when flying in mountainous or hilly areas, these high terrain features can obstruct or reflect the radio waves, leading to inaccurate readings.

Terrain Error occurs because the radio waves may not reach the aircraft directly or could be distorted by the surrounding landscape, thus causing the pilot to misinterpret the aircraft's position relative to the beacon. This can result in navigational errors, such as drifting off course or misjudging the aircraft's distance from the NDB.

Understanding Terrain Error is crucial for pilots operating in regions with significant elevation changes, as it emphasizes the importance of cross-referencing NDB readings with other navigational aids or techniques. This awareness helps pilots maintain situational awareness and enhance safety when flying in challenging environmental conditions.