Spatial disorientation was studied in a gondola centrifuge. Method: The subjective visual horizontal (SVH) was measured in (i) seven subjects at 1g, 1.1G, 1.7G, and 2.5G, and (ii) at 2.5G in eleven subjects with the head rotated 20 degrees to the right or left and after yaw head movements. Results: Acceleration of the centrifuge caused a tilt of the SVH with respect to the gravitoinertial horizontal. The SVH-tilt appeared to be the sum of two components: one large (5-40 degrees) rapidly decaying, and one small (0-10 degrees) and persistent. The decay occurred more slowly at higher G-levels. Changes in yaw head position also induced a SVH-tilt (15-30 degrees) - a Coriolis illusion - the direction of which was dependent on the direction of head turn and the strategy for orientation (allocentric or egocentric). In the right or left head positions there were small (2-4 degrees) SVH-tilts - G-excess illusions. Conclusions: Semicircular canal-induced disorientation is more persistent if the resultant gravity force is increased. Head turns in yaw induce disorientation in roll. Data are dependent on the subject´s strategy for orientation. In oblique head positions there is a roll G-excess illusion. The small magnitude of this might suggest the influence of visual cues.