Effects of Scene Content and Display Configuration on Nap-of-the-Earth Flight Performance in a High Fidelity Simulator

Research was conducted in the Simulator Training Research Advanced Testbed for Aviation to determine the effects of varying scene content and display configuration on nap-of-the-earth flight performance. Three levels of both tree density and texture detail and three configurations of the fiber optic helmet mounted display were selected for analysis. Nine different flight environments were created from all combinations of tree density and texture detail and placed along flight routes with varying topography. Twelve experienced U. S. Army aviators were instructed to fly below 25 ft of altitude and 40 kts of airspeed. Data were collected with and without information from flight instruments. Analyses of the 12 primary variables revealed differences between the scenes with and without trees but not between the two conditions with trees. Texture detail had no significant effect on airspeed control; however, it did produce a small but significant effect on altitude control. The three configurations of the fiber optic helmet mounted display showed no significant main effects on performance.