Which of the following is NOT a function of gyroscopic instruments?

Gyroscopic instruments are essential components in modern aviation, primarily utilized for flight orientation and stability. They serve several critical functions, including indicating orientation (such as in the attitude indicator), indicating movement (such as in the turn coordinator), and ensuring flight stability through instruments like the vertical speed indicator and heading indicator.

The function of providing navigation routes is not a role performed by gyroscopic instruments. Navigation typically relies on GPS, VOR (VHF Omnidirectional Range), and other non-gyroscopic aids that help define and follow specific flight paths and waypoints. While gyroscopic instruments can support a pilot's situational awareness during navigation by indicating the aircraft's position and attitude, they do not contribute to the actual routing or navigation decisions made by a pilot.

Thus, the emphasis on orientation, movement, and stability within the context of gyroscopic instruments delineates their primary purposes, highlighting navigation routes as a function outside their scope.