Abstract: A method for controlling brakes is provided. The method may include the steps of detecting an aircraft speed, determining the aircraft speed is within a range from an antiskid-dropout speed to a locked-wheel-protection-engagement speed, and determining an input of a pressure controller has a value less than a pressure maximum threshold. A current command that is output from the pressure controller may be detected at or above a threshold value. The states of the pressure controller and pressure controller input may be reset in response to the current command being at or above the threshold value for a predetermined duration.

Abstract: A method for controlling brakes is provided. The method comprises detecting an imminent skid by an anti-skid controller/deceleration controller (ASK/DK). The ASK/DK outputs at least one of a negative desired pressure command to a pressure control unit (PK) in response to detecting the imminent skid and causes a current command output from the PK to be reduced to release braking pressure if the negative desired pressure command minus a measured feedback pressure is greater than a deadband of the PK or outputs a negative desired force command to a force control unit (ForK) in response to detecting the imminent skid and causing a current command output from the ForK to be reduced to release braking force if the negative desired force command minus a measured feedback force is greater than a deadband of the Fork. A brake control system is also provided.

Abstract: A system for two-stage determination of a brakefail of an aircraft brake system includes an aircraft brake. The aircraft brake is configured to receive a current command value, convert the current command value to a braking pressure and output a detected pressure value corresponding to the braking pressure. The system also includes a brake control unit (BCU) configured to determine a pressure command value, convert the pressure command value to the current command value and to determine whether a brakefail event has occurred based on the pressure command value, the current command value and the detected pressure value.

Abstract: A method for controlling brakes is provided, The method comprises detecting an imminent skid by an anti-skid controller/deceleration controller (ASK/DK). The ASK/DK outputs at least one of a negative desired pressure command to a pressure control unit (PK) in response to detecting the imminent skid and causes a current command output from the PK to be reduced to release braking pressure if the negative desired pressure command minus a measured feedback pressure is greater than a deadband of the PK or outputs a negative desired force command to a force control unit (ForK) in response to detecting the imminent skid and causing a current command output from the ForK to be reduced to release braking force if the negative desired force command minus a measured feedback force is greater than a deadband of the Fork. A brake control system is also provided.

Abstract: A method for controlling brakes is provided. The method may include the steps of detecting an aircraft speed, determining the aircraft speed is within a range from an antiskid-dropout speed to a locked-wheel-protection-engagement speed, and determining an input of a pressure controller has a value less than a pressure maximum threshold. A current command that is output from the pressure controller may be detected at or above a threshold value. The states of the pressure controller and pressure controller input may be reset in response to the current command being at or above the threshold value for a predetermined duration.

Abstract: A system for two-stage determination of a brakefail of an aircraft brake system includes an aircraft brake. The aircraft brake is configured to receive a current command value, convert the current command value to a braking pressure and output a detected pressure value corresponding to the braking pressure. The system also includes a brake control unit (BCU) configured to determine a pressure command value, convert the pressure command value to the current command value and to determine whether a brakefail event has occurred based on the pressure command value, the current command value and the detected pressure value.

Abstract: In various embodiments, a method associating received coefficient of friction data to runway friction estimation map elements. Also, the method may include aggregating the received determined coefficient of friction data into a friction estimation map.

Abstract: In various embodiments, a method for utilizing a determined coefficient of friction along a portion of a runway is disclosed. The method may include receiving, by a brake control unit, friction estimation map data for a specific runway. The method may include setting, by the brake control unit, a condition of the braking control algorithm based on the received friction estimation map data. The method may include initiating, by the brake control unit, a brake control system to slow a wheel of an aircraft based on the braking control algorithm.

Abstract: A runway traction estimation and reporting method and computer readable medium is provided. Upon detection of a landing event, a runway traction estimation and reporting method provides for various measurements and calculations to estimate the traction of the runway and create a traction map of the runway. A computer readable medium may contain instructions for a runway traction estimation and reporting processor directing the processor to perform various measurements and calculations to estimate the traction of the runway. The processor may communicate with a ground station or with other aircraft to produce collaborative results.

Abstract: A runway traction estimation and reporting method and computer readable medium is provided. Upon detection of a landing event, a runway traction estimation and reporting method provides for various measurements and calculations to estimate the traction of the runway and create a traction map of the runway. A computer readable medium may contain instructions for a runway traction estimation and reporting processor directing the processor to perform various measurements and calculations to estimate the traction of the runway. The processor may communicate with a ground station or with other aircraft to produce collaborative results.

Abstract: Systems and methods for a tire/runway friction property estimation method based on measured wheel speed, calculated acceleration, wheel reference and tire normal force estimation are disclosed. Based on the resulting estimations, a map and/or function of position for the friction properties may be formed and transmitted to external systems after an aircraft stop is completed.

Abstract: In various embodiments, a method for utilizing a determined coefficient of friction along a portion of a runway is disclosed. The method may include receiving, by a brake control unit, friction estimation map data for a specific runway. The method may include setting, by the brake control unit, a condition of the braking control algorithm based on the received friction estimation map data. The method may include initiating, by the brake control unit, a brake control system to slow a wheel of an aircraft based on the braking control algorithm.

Abstract: In various embodiments, a method associating received coefficient of friction data to runway friction estimation map elements. Also, the method may include aggregating the received determined coefficient of friction data into a friction estimation map.

Abstract: Systems and methods for detecting the onset of wheel skids and controlling brake torque to achieve efficient and smooth braking performance are described herein. A brake control system may utilize an algorithm, along with substantially real-time measured values to assist with controlling brake torque to achieve efficient and smooth braking performance. A history of wheel speed information, such as wheel speed information associated with one or more landing event, may also be used to iteratively estimate tire/runway friction properties.

Abstract: Systems and methods for a tire/runway friction property estimation method based on measured wheel speed, calculated acceleration, wheel reference and tire normal force estimation are disclosed. Based on the resulting estimations, a map and/or function of position for the friction properties may be formed and transmitted to external systems after an aircraft stop is completed.