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An illusion that a pilot can experience when he or she returns to level flight after an intentional or unintentional prolonged bank turn. A pilot who enters a banking turn to the left will initially have a sensation of turning in the same direction. If the left turn continues for 20 s or more, the pilot is likely to feel that the airplane is no longer turning to the left. If the pilot attempts to level the wings at this point, this action will produce a compelling sensation that the airplane is turning and banking to the right. Failure to check the instruments may lead the pilot to reenter the original left turn in an attempt to counteract the sensation of a right turn, but the airplane is still turning to the left and losing altitude. If the disoriented pilot pulls back on the controls, the spiral will tighten and the loss of altitude will increase, making the situation even worse.