In aviation, a graveyard spiral is a dangerous spiral dive entered into accidentally by a pilot who is not trained or not proficient in instrument flight when flying in instrument meteorological conditions (IMC).
Graveyard spirals are most common in nighttime or poor weather conditions where no horizon exists to provide visual correction for misleading inner-ear cues. Graveyard spirals are the result of several sensory illusions in aviation which may occur in actual or simulated IMC, when the pilot loses awareness of the aircraft's attitude. In other words, the pilot loses the ability to judge the orientation of his aircraft due to the brain’s misperception of spatial cues.
The graveyard spiral consists of both physiological and physical components. Mechanical failure is often a result but generally not a causal factor, as it is the pilot’s sense of equilibrium which leads to the spiral dive. Flying by “the seat of the pants,” and failing to recognize and/or respond to instrument readings is the most common source of controlled flight into terrain where a plane controlled by a pilot impacts ground.
Read more about Graveyard Spiral: Physics of The Graveyard Spiral, Vestibular Aspects of The Graveyard Spiral
Famous quotes containing the words graveyard and/or spiral:
“Since the last one in a graveyard is believed to be the next one fated to die, funerals often end in a mad scramble.”
—Administration in the State of Texa, U.S. public relief program (1935-1943)
“What is art,
But life upon the larger scale, the higher,
When, graduating up in a spiral line
Of still expanding and ascending gyres,
It pushes toward the intense significance
Of all things, hungry for the Infinite?
Art’s life,—and where we live, we suffer and toil.”
—Elizabeth Barrett Browning (1806–1861)