Yaw String

Yaw string pictured in the middle of image - blue string taped to canopy

The yaw string is a short piece of yarn taped to the canopy(clear, plexiglass "windshield"). 

• Primary flight reference instrument in gliders

• Valued for its high sensitivity

• Does not require the pilot to look down at the instrument panel

• Even the most sophisticated modern racing sailplanes are fitted with yaw strings

• Referenced constantly throughout the flight

If the yaw string is off center, the glider is flying sideways through the air. This creates undesirable drag when the airflow pushes against the side of the fuselage and at an angle across the wing instead of straight across as it should. The result: an unnecessary loss of performance. It is important to keep the yaw string straight by using the controls properly.

History

The yaw string dates from the earliest days of aviation, and actually was the first flight instrument. The Wright Brothers used a yaw string on their 1902 glider tied on their front mounted elevator. Wilbur Wright is credited with its invention.