Graveyard Spiral

A graveyard spiral, also called a suicide spiral, deadly spiral, death spiral or vicious spiral, is a dangerous spiral dive that a pilot who is not trained or proficient in instrument flight can enter by accident, most often at night or in poor weather when no visible horizon is available to correct the misleading cues coming from the inner ear. It results from a form of spatial disorientation in which the pilot vestibular sense of balance produces the sensation of flying level even though the aircraft is actually banking and losing altitude, so that flying by that false bodily sense rather than by the flight instruments is a common cause of controlled flight into terrain, in which an aircraft still under the pilot own control strikes the ground. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/