Which Terrain Flight mode is characterized by relatively constant airspeed and varying altitude, defined in NVG training as skids 25-80 ft. above the highest obstacle?

The correct answer is characterized by the specific flying technique utilized to navigate terrain while maintaining awareness of obstacles and ensuring safe operation. This mode, known as the Contour flight mode, involves maintaining a relatively constant airspeed while flying at an altitude that varies in accordance with the terrain features below, specifically aiming to keep the helicopter's skids between 25 to 80 feet above the highest obstacle.

In NVG (Night Vision Goggles) training, this altitude range is crucial as it allows for effective obstacle avoidance and terrain following while still optimizing for airspeed. The operator must be adept at making slight adjustments to altitude to keep safely above potential hazards like trees, hills, or buildings while traveling forward. The focus is on adapting to the terrain's undulations and variations while ensuring the speed remains steady.

In contrast, other flight modes such as Low Level, NOE (Nap-of-the-Earth), and Hover serve different operational purposes and involve different techniques. Low Level generally denotes flying with less variability in altitude but can include broader altitude ranges. NOE focuses on flying very close to the terrain to reduce detection risk, often requiring more dynamic altitude changes. Hover involves maintaining a stationary position in the air, which does not fit with the described characteristics of maintaining constant