Accession Number : ADA956114

Title :   Effects of Magnification and Visual Accommodation on Aimpoint Estimation in Simulated Landings With Real and Virtual Image Displays.

Descriptive Note : Technical paper,

Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION MOFFETT FIELD CA AMES RESEARCH CENTER

Personal Author(s) : Randle, Robert J. ; Roscoe, Stanley N. ; Petitt, John C.

Report Date : OCT 1980

Pagination or Media Count : 28

Abstract : Twenty professional pilots observed a computer-generated airport scene during simulated autopilot-coupled night landing approaches and at two points (20 sec and 10 sec before touchdown) judged whether the airplane would undershoot or overshoot the aimpoint. Visual accommodation was continuously measured using an automatic infrared optometer. Experimental variables included approach slope angle, display magnification, visual focus demand (using ophthalmic lenses), and presentation of the display as either a real (direct view) or a virtual (collimated) image. Aimpoint judgments shifted predictably with actual approach slope and display magnification. Both pilot judgments and measured accommodation interacted with focus demand with real-image displays but not with virtual-image displays. With either type of display, measured accommodation lagged far behind focus demand and was reliably less responsive to the virtual images. Pilot judgments shifted dramatically from an overwhelming perceived-overshoot bias 20 sec before touchdown to a reliable undershoot bias 10 sec later. Landing approach, Visual perception, Ground-referenced display, Image magnification, Visual accommodation, Aimpoint estimation.

Descriptors :   *AIRCRAFT, *AIRPORTS, *LANDING, *NIGHT LANDINGS, ANGLES, APPROACH, AUTOMATIC, AUTOMATIC PILOTS, BIAS, COMPUTERS, IMAGES, LENSES, MAGNIFICATION, NIGHT, OPTOMETERS, PERCEPTION, PILOTS, SLOPE, VARIABLES, VISUAL PERCEPTION.

Subject Categories : Military Aircraft Operations

Distribution Statement : APPROVED FOR PUBLIC RELEASE