SAE AS440A

This SAE Aerospace Standard (AS) covers autoatic pilots intended for use on aircraft to automatically operate the primary and trim aerodynamic controls to maintain stable flight and/or to provide maneuvering about any of the three axes through servo control. Automatic control functions essential for primary or augmented flight control are excluded.

To establish essential minimum safe performance standards for automatic pilots primarily for use with turbine powered subsonic transport aircraft, the operation of which may subject the instrument to the environmental conditions specified in Section 3.3.