Apparent Instrument Horizon Deflection during and Immediately Following Rolling Maneuvers

摘要

The present study was the result of recent reports by pilots of apparent visual bending or bowing of instrument horizons during and immediately following ascending rolling maneuvers in the F-14 aircraft, and it investigates the probability that normal reflex actions may partially account for these reports. The results of these tests suggest that the VOR can produce an apparent deflection of the instrument horizon (actually an apparent flicking back and forth) during and after roll maneuvers involving high peak angular velocities. The perceptual aberration could be disturbing to a pilot attempting to use his instrument horizon and could lead to suspecting instrument malfunction if the pilot were unaware of this phenomenon. The reported distortions of the instrument horizon could be the result of the VOR which tends to stabilize the eye relative to the Earth during angular acceleration of the head, and therefore reflexly displaces the eye relative to objects such as flight instruments that move with the head. (Author)