Automatic airspeed engage/disengage

US4371938A · kind A · utility

Assignee

• UNITED TECHNOLOGIES CORPORATION · US

Inventors

• Stuart C. Wright · Woodbridge, US
• Don L. Adams · Bartlesville, US
• William C. Fischer · Monroe, US
• David J. Verzella · Guilford, US

Key dates

• Filing date: Mar 30, 1981
• Grant date: Feb 1, 1983
• Expiry date: Mar 30, 2001

Classification

• Technology area (CPC G): Physics
• CPC primary: G05D1/0858
• WIPO field: Control
• WIPO sector: Instruments

Abstract

In an automatic flight control system (FIG. 1) an airspeed control engage function (84) is automatically engaged (136, FIG. 2; 244, FIG. 4) in response to airspeed above a threshold magnitude, such as 45 knots (88, FIG. 2) and will remain engaged (subject to a fault condition, 135) until the airspeed command (75) reaches a predetermined, insignificant magnitude (132). An airspeed error integrator 241 which accommodates the difference between a reference attitude and an attitude required for a reference airspeed, does not react to large airspeed errors as a consequence of pilot maneuvering due to pilot force on the control stick (35, 109) opening the input (252, FIG. 4) to the airspeed error integrator.