/Disengagement For Reverse Propeller Protection
Abstract

An engine and propeller control system (EPECS) of an aircraft includes a propeller coupled to an aircraft engine. The propeller includes a plurality of blades, each of the blades coupled to an actuator configured to adjust the blades into a first pitch to produce forward thrust, a second pitch to produce reverse thrust, or flight-idle position to idle the propeller. A controller receives a reverse thrust command signal indicating a request by an aircraft operator to invoke the second pitch, and controls the actuator to invoke the flight-idle position prior to invoking the second pitch. The controller is configured to erroneously determine an aircraft on-ground state during which the aircraft is touching ground, and generate alerts indicating that the reverse thrust command signal was generated prior to touching the ground and that the propeller will be adjusted from the flight-idle position into the second pitch.

Full Text

What is claimed is:

An engine and propeller control system (EPECS) of an aircraft includes a propeller coupled to an aircraft engine. The propeller includes a plurality of blades, each of the blades coupled to an actuator configured to adjust the blades into a first pitch to produce forward thrust, a second pitch to produce reverse thrust, or flight-idle position to idle the propeller. A controller receives a reverse thrust command signal indicating a request by an aircraft operator to invoke the second pitch, and controls the actuator to invoke the flight-idle position prior to invoking the second pitch. The controller is configured to erroneously determine an aircraft on-ground state during which the aircraft is touching ground, and generate alerts indicating that the reverse thrust command signal was generated prior to touching the ground and that the propeller will be adjusted from the flight-idle position into the second pitch.
Timeline
Filed
04/27/2026
Published
09/03/2026
Granted
Not Available
IPC Codes(4)
B64C 11/30:Blade pitch-changing mechanisms
B64C 11/34:automatic
B64D 31/06:actuated automatically