The Effects of Head-Up Display (HUD) Pitch Ladder Articulation, Pitch Number Location and Horizon Line Length on Unusual Attitude Recoveries for the F-16

The current trend in fighter cockpits is to provide flight references on the Head-Up Display pitch ladder format, but because pitch ladder formats are superimposed on the outside world, pilots who reference them can become spatially disoriented. Presently, pitch ladder formats display abstract symbology to convey attitude information and to overcome the spatial disorientation problem. This evaluation examined such abstract coding for the F- 16 aircraft. Specifically, the study focused on the effects of pitch bar articulation, pitch number location and horizon line length on the pilots ability to recover from unusual attitudes. Performance data were collected for nose low and nose high attitudes. Also, Subjective Workload Assessment Technique SWAT and Subjective Workload Dominance SWORD data were collected to provide a measure of pilot mental workload. Pilot situation awareness was also evaluated. Three pitch ladder formats were evaluated the F-16 Block 40 pitch ladder, a pitch ladder with articulated pitch bars in the lower hemisphere and a pitch ladder with articulated bars in the upper and lower hemisphere. Also, two locations for pitch numbers were evaluated. Results consistently showed that pitch bar articulation in the lower hemisphere yielded the most favorable results, while a best location for pitch numbers was not found. A horizon line that extended the entire width of the HUD was the favorite among pilots, but did not significantly improve performance. Human EngineeringHE, Situation AwarenessSA, Head-Up DisplayHUD, Subjective Workload DominanceSWORD, Subjective Workload Assessment TechniqueSWAT.