The flight attitude skill is the association of the flight path of the aircraft with appropriate visual references. Regardless of how well pilots can execute the skill of controlling the aircraft they must understand the fundamental relationship between these controlling inputs and the effect on the flightpath of the aircraft. Our best visual reference in this regard is the relationship of fixed points on the aircraft in the line of our vision to the line of the horizon. Using these references and some guided experience a pilot can determine if the aircraft is following a flight path particularly with respect to pitch and roll. For glider pilots the yaw string is a particularly effective reference for yaw. Even for aircraft flying under instrument meteorological conditions, the same principles apply. In this state the instruments mimic the visual flying conditions by providing the equivalent attitude indicators.