Why is flying over a large field considered tactically unsound?

Flying over a large field is considered tactically unsound primarily because it increases the chances of enemy detection. Large, open areas, such as fields, offer little in the way of cover or concealment for aircraft, making them more vulnerable to visual and radar detection. When aircraft are in open airspace, enemy units, whether ground troops or air defense systems, can more easily spot them from a distance.

Additionally, flying in such areas can limit the opportunities for evasive maneuvers due to the lack of terrain features that could be used to break the line of sight with enemies. Pilots are trained to use the landscape to their advantage, and open fields do not provide the necessary concealment that is critical in avoiding detection. As a result, tactical planning generally requires avoiding large fields when possible to enhance chances of remaining undetected and to improve overall mission success rates.