Which of the following statements accurately defines NOE flight?

The statement that accurately defines NOE (Nap-of-the-Earth) flight is that it utilizes variable airspeeds. NOE flight is characterized by flying at very low altitudes, often close to the terrain, to enhance concealment from enemy observation and to decrease vulnerability to radar detection. This type of flight requires pilots to adapt their airspeeds based on the varying terrain and obstacles, such as hills, trees, and other features. Therefore, the ability to adjust airspeed is crucial for maintaining control and avoiding hazards while navigating through complex landscapes.

Maintaining a constant airspeed or altitude, as mentioned in other options, does not align with the dynamic nature of NOE operations, where pilots need to make frequent adjustments. Additionally, while NOE flight techniques enhance survivability, it may not always be the safest option in every scenario, as various factors including environmental conditions and mission requirements can influence the safety and effectiveness of this flight profile.