Abstract: A system for performing frequency response health monitoring of a servo valve prior to flight of an aircraft may comprise: the servo valve; and a brake controller in electrical communication with the servo valve, the brake controller configured to: determine the brake controller is powering up, supply a variable current to the servo valve to perform the frequency response health monitoring to the servo valve in response to determining the brake controller is powering up, and determine a health status of the servo valve based on the frequency response health monitoring.

Abstract: Systems and methods for shutoff valve control are provided. The system may receive a first hardware logic input, a second hardware logic input, and a weight-on-wheels (WOW) status wherein each of the first hardware logic input, the second hardware logic input, and the WOW status report a binary true or a false. The system may open the shutoff valve when each of the first hardware logic input, the second hardware logic input, and the WOW status report true. The system may close the shutoff valve when any of the first hardware logic input, the second hardware logic input, and the WOW status report false.

Abstract: A braking system is disclosed. In various embodiments, the brake system includes a brake assembly; a hydraulic braking subsystem having a hydraulic brake actuator configured to operate the brake assembly; and an electric braking subsystem having an electric brake actuator configured to operate the brake assembly.

Abstract: A system for landing gear prognostic and health management may comprise a stroke measurement component and a pin configured to translate relative to the stroke measurement component. The pin may include a plurality of graduations. The pin may be configured such that a graduation corresponding to a stroke length of the landing gear may be visible through a viewing window of the stroke measurement component.

Abstract: A brake control system of the present disclosure includes an accelerometer coupled to an axle. A brake control unit is configured to receive an axle acceleration signal indicative of an axle acceleration from the accelerometer, and decrease a braking command pressure in response to the axle acceleration being greater than a threshold acceleration value.

Abstract: A brake control system of the present disclosure calibrates a servo valve and calculates a calibrated transfer function associated with the servo valve for precise braking in open-loop mode. The calibration steps may include determining i) whether an aircraft is on a ground surface, ii) whether the aircraft is not moving relative to the ground surface, and iii) whether braking is applied to a brake system of the aircraft. The brake control unit may calibrate the servo valve in response to the brake control unit determining that i) the aircraft is on the ground surface, ii) the aircraft is not moving relative to the ground surface, and iii) the braking is not applied to the brake system of the aircraft. The calibration process includes sending two or more test currents to the servo valve, and determining braking pressures associated with those test currents to calculate the transfer function.

Abstract: An autobrake system includes a brake control unit (BCU), and a control knob in electronic communication with the BCU. The BCU is configured to receive a position signal from the control knob, the position signal corresponding a position of the control knob. The BCU is configured to select a braking deceleration based upon the position signal, wherein the braking deceleration continuously changes between a minimum braking deceleration and a maximum deceleration in response to the control knob moving between a first position and a second position for fine tuning of the braking deceleration.

Abstract: A method for brake health monitoring may include sending, by a brake control unit (BCU), a brake command signal to initiate a braking maneuver, and receiving a first wheel speed signal and a second wheel speed signal corresponding to the speed of first and second wheels, respectively, during the braking maneuver. The BCU may detect that the speed of the first wheel is greater than the speed of the second wheel by a predetermined threshold, and, in response thereto, post an alert indicating a failure in a brake control component associated with the first wheel based upon the detection of the speed of the first wheel being greater than the speed of the second wheel by the predetermined threshold.

Abstract: Systems and methods for antiskid brake control include a brake control unit (BCU) configured to generate a brake command signal adjusted for a wide range of brake coefficient of friction based upon a real-time aircraft kinetic energy value. A method for antiskid brake control includes receiving, by a BCU, an aircraft mass and a wheel speed signal. The BCU determines an aircraft speed based upon the wheel speed signal and calculates the aircraft kinetic energy using the aircraft speed and aircraft mass. One or more antiskid parameters (e.g., proportional gain, a derivative gain, and/or deceleration target value) are adjusted based upon the aircraft kinetic energy to generate, by the brake control unit, an optimal antiskid brake command signal.

Abstract: A braking system is disclosed. In various embodiments, the braking system includes a brake stack; an actuator configured to apply a compressive load to the brake stack; a servo valve coupled to a power source and to the actuator; and a brake control unit configured to operate the servo valve at a current ramp rate in response to a pedal deflection signal, wherein the current ramp rate is determined via a relationship between the current ramp rate and a brake pressure command signal.

Abstract: A method for cooling a brake system is disclosed. In various embodiments, the method includes determining a turnaround time parameter; determining a time to cool parameter; determining a parameter difference between the time to cool parameter and the turnaround time parameter; and adjusting a flow of air directed at the brake system based on the parameter difference.

Abstract: An autobrake brake control system includes a shutoff valve configured to receive a hydraulic fluid, a servo valve configured to receive the hydraulic fluid from the shutoff valve and configured to provide the hydraulic fluid to apply braking force to a wheel via a hydraulic line, and a brake control unit in electronic communication with the shutoff valve. The brake control unit is configured to detect a weight-on-wheel (WOW) condition of a nose landing gear, and the brake control unit controls the shutoff valve in response to detecting the WOW condition of the nose landing gear.

Abstract: An emergency park brake system of an aircraft may include an electrical power interface, an electromechanical actuator, and a hydraulic brake valve. The electrical power interface may be configured to receive electrical power from a power source. The electromechanical actuator may be in selective power receiving communication with the electrical power interface and the electromechanical actuator may be mechanically coupled to and configured to selectively actuate the hydraulic brake valve. The electrical connection between the electromechanical actuator and the electrical power interface may be based on an emergency braking input.

Abstract: A method for controlling brakes includes receiving, by a controller, a first wheel speed from a first wheel speed sensor of a first wheel arrangement, receiving, by the controller, a second wheel speed from a second wheel speed sensor of a second wheel arrangement, calculating, by the controller, a pressure correction, and adjusting, by the controller, a pressure command for at least one of the first wheel arrangement and the second wheel arrangement.

Abstract: A method for active brake selection, in accordance with various embodiments is disclosed. The method comprises detecting an outbound taxiing event for an aircraft. The method further comprises determining whether an inboard or outboard brake has less wear than a respective inboard or outboard brake on a respective landing gear. The method may further comprise selecting an inboard or outboard brake to use during the outbound taxiing event.

Abstract: An emergency park brake system of an aircraft may include an electrical power interface, an electromechanical actuator, and a hydraulic brake valve. The electrical power interface may be configured to receive electrical power from a power source. The electromechanical actuator may be in selective power receiving communication with the electrical power interface and the electromechanical actuator may be mechanically coupled to and configured to selectively actuate the hydraulic brake valve. The electrical connection between the electromechanical actuator and the electrical power interface may be based on an emergency braking input.

Abstract: The present disclosure provides an actuator assembly having a ball nut comprising a helical track and a ball screw. The ball screw of the actuator assembly includes a first translation bearing track having a first diameter, wherein the helical track and the first translation bearing track form a first translation bearing raceway in which a first translation bearing ball is disposed. The ball screw further includes a second translation bearing track having a second diameter, wherein the helical track and the second translation bearing track form a second translation bearing raceway in which a second translation bearing ball is disposed. The first diameter and the second diameter are not equal.

Abstract: A system for performing brake testing during flight of an aircraft, in accordance with various embodiments, includes a landing gear having at least one wheel assembly. The system further includes a brake configured to apply a braking force to the at least one wheel assembly. The system further includes a brake controller configured to determine a landing event indicating that the aircraft is approaching a landing, control the brake to apply a testing brake force to the at least one wheel assembly in response to determining the landing event, and determine an operational status of the brake based on the testing brake force.

Abstract: A brake wear component is disclosed. In various embodiments, the component includes a linear position sensor disposed within a housing and configured to contact a pressure plate of a brake mechanism; a bias element coupled to the linear position sensor and configured to bias the linear position sensor a distance away from the pressure plate during a deactivated state; and an actuating mechanism coupled to the linear position sensor and configured to translate the linear position sensor toward the pressure plate during an activated state.

Abstract: A system for landing gear prognostic and health management may comprise a stroke measurement component and a pin configured to translate relative to the stroke measurement component. The pin may include a plurality of graduations. The pin may be configured such that a graduation corresponding to a stroke length of the landing gear may be visible through a viewing window of the stroke measurement component.