A pilot's perception of variables presented on the Electronic Flight I
nstrument System, EFIS, was investigated. A stimulus response techniqu
e was used to determine the accuracy and speed of the perception proce
ss. By varying the exposure time of the stimuli, it is shown that the
perception of a variable's magnitude is faster and more accurate than
the perception of the first derivative or rate of that variable. Resul
ts of experiments on roll and pitch attitude perception, the influence
of scale division, and the perception of the indicated airspeed, are
shown. Copyright (C) 1997 Elsevier Science Ltd.