<title>Analysis of azimuth head motion in rotary-wing flight using various helmet-mounted display configurations</title>

<title>Elevation head motion in rotary-wing flight with helmet-mounted displays</title>

“…As was found with the analysis of azimuth head motion, 9 there was great variability in head position data, both within and between subjects. This is not a surprising finding in view of the many facts involved in rotary-wing flight period.…”

“…As discussed in Rostad et al, 9 Verona et al 7 identified two major factors that influence head motion characteristics in rotary-wing flight. The first factor is aircraft configuration, which encompasses crewstation design, seating configuration (tandem vs. side-by-side), seat adjustment (fore/aft and up/down), and transparency (window) locations.…”

“…The head motion distributions analyzed herein were multimodal and deviated from normality. It was shown in Rostad et al 9 (2001) that the classical technique for comparing distributions (Chi-square analysis) was ineffective. In addition, it was shown that the Spearman's rank-correlation procedure was useful for investigating correlation of head motion parameters for the HMD conditions within subjects.…”

“…An analysis of azimuth head motion data for the slalom maneuver only has been completed and recently reported. 9 This paper continues the investigation of the head motion data by reporting the analysis of the elevation head motion for the same flights and conditions used in the azimuth analysis.…”

“…While summarized in the following sections, full descriptions of the instrumentation, HMD modes, visual environments, and flight maneuvers are provided in Rostad et al 9 (2001).…”