Optical and Biodynamic Evaluation of the Helmet Integrated Display Sight System (HIDSS) for the RAH-66 Comanche Development and Validation Program Phase.

Abstract : The Development and Validation phase Helmet Integrated Display Sight System (HIDSS) for the RAH-6E Comanche was evaluated. The HIDSS consists of an integrated helmet, a helmet-mounted display consisting of a right and a left multifunction display, a helmet tracking system, a boresight reticle unit, and the associated electronics. The evaluation consisted of biodynamic, optical, and visual performance measures. Measurements show that the HIDSS fails to provide acceptable weight and center of mass performance. At a value of 2.62 kg, the head supported weight exceeds the maximum allowable value. Image quality was acceptable except for the areas of contrast ratio (shades of gray), luminance uniformity, and modulation transfer function. Additional human factors engineering concerns surfaced during the evaluation. These included restrictions on pilot head movements due to cathode ray tube size and location, extraneous reflections, single visor configuration, and interpupillary distance extreme adjustment effect on monocular operation.