In current spatial orientation models, vertical acceleration (heave) is not coupled with pilot pitch perception, although such a coupling may be present. Therefore, in this study it is investigated whether a heave cue can increase perceived pitch in pilots.

Airline pilots (n = 20) performed a pitch perception task in a hexapod simulator. A level change maneuver, with the simulator cabin pitching up and back down, was presented with different maximum pitch angles. After the maneuver, pilots indicated the maximum perceived pitch angle. This motion was presented either with or without a brief (1.25s or 1.5s) heave cue, that was timed to the onset of the pitch motion. Two timings and magnitudes of the heave cue were used to investigate these factors.

The results indicate that the heave cue significantly increased pilot pitch perception by 1.88°, p < 0.001. The maximum pitch angle was 2.69° underestimated without heave and 1.42° underestimated with heave. A higher heave magnitude, relative to a lower, resulted in a significantly larger estimation of the pitch angle, δ = 0.47°, p = 0.009. Earlier timing of the heave cue resulted in marginally significantly higher pitch perception than later timing, δ = 0.43°, p = 0.069. Interestingly, if heave was presented without pitch motion, pilots still estimated 2.66° pitch on average.

The results suggest that heave cueing increases perceived pitch in pilots, even when the heave cues are shorter in duration than cues that would be present in the actual maneuver in flight. Heave cues timed to the onset of pitch motions can thus possibly be used to enhance pilot pitch perception in hexapod simulators.