Effect of a Monocular Helmet-Mounted Display on Aircrew Health: A Longitudinal Cohort Study of Apache AH Mk 1 Pilots -(Vision and Handedness).

摘要

The AH-64 Apache attack helicopter provides forward-looking infrared and instrumentation symbology to the pilot, via a right-sided monocular helmet-mounted display (HMD). The optical input to the two eyes differs and can lead to binocular rivalry. Several reports have identified visual issues arising in AH-64 pilots during and after flight, most commonly headaches, visual discomfort, and eye fatigue. The possible residual impact of the long-term use of a monocular HMD on visual performance has not previously been studied. This joint United Kingdom-United States study followed for 10 years a cohort of newly exposed AH-64D pilots and a control population of non AH-64D pilots. Visual function data and subjective symptoms were collected via an expanded battery of monocular and binocular tests and annual questionnaires. Data were examined for 46 exposed and 70 control subjects. No statistically significant differences between exposed and control groups were noted for any of the visual tests. In-flight, headaches and visual discomfort were reported respectively by 58 and 23 percent of the control subjects, and 56 and 51 percent of the exposed subjects. The study found no significant evidence that the prolonged use of the AH-64 monocular HMD produces any meaningful differential vision changes between the two eyes, or that the visual performance of exposed subjects differed from that of control subjects.