Abstract: An aircraft brake control system accommodates desired yaw for steering, while substantially eliminating undesired yaw. The system assesses brake command signals from the pilot, signals corresponding to aircraft parameters, and signals based on brake control parameters, and determines therefrom an amount of yaw desired by the pilot. The instantaneous yaw rate is monitored and compared to the desired yaw rate. An error signal corresponding to the difference between instantaneous and actual yaw rates is calculated and that error signal is employed to modify a braking differential between right and left brakes to eliminate or substantially reduce the undesired yaw.

Abstract: An aircraft brake control system accommodates desired yaw for steering, while substantially eliminating undesired yaw. The system assesses brake command signals from the pilot, signals corresponding to aircraft parameters, and signals based on brake control parameters, and determines therefrom an amount of yaw desired by the pilot. The instantaneous yaw rate is monitored and compared to the desired yaw rate. An error signal corresponding to the difference between instantaneous and actual yaw rates is calculated and that error signal is employed to modify a braking differential between right and left brakes to eliminate or substantially reduce the undesired yaw.

Abstract: A method for aircraft brake wear optimization includes processes by which the actual instantaneous temperature of brakes can be determined during taxi braking operations. The invention is particularly applicable to carbon disc brakes in aircraft. In the system, the energy absorbed by the carbon disc brakes during taxiing operation is calculated and a conversion made from energy absorbed to disc temperature is made. The system uses less than a full complement of brakes during taxiing such that the brakes actually employed during taxiing are at elevated temperatures, which are characterized by improved brake wear. The system provides substantially instantaneous thermal information, in contrast to the prior art relying upon thermal measurements rather than energy calculations.

Abstract: Torque tubes with better total failure performance is provided. The torque tube comprises a plurality of reinforcement members made from a second material with a higher temperature strength than the first material. In preferred embodiments, the reinforcement members are tungsten rods. The reinforcement members are located concentrically around a central axis of the torque tube and each reinforcement member spans a center line of a central tube of the torque tube and spans a majority of a longitudinal length of the torque tube. In preferred embodiments, the reinforcement members are drive keys.

Abstract: A method of diagnosis and prognosis for various operative systems is provided so that maintenance can be efficiently and effectively scheduled and provided. The invention is applicable to a broad range of systems, but particularly to aircraft brake systems and tires. An aircraft brake may be modeled by attributing brake wear factor values to various parameters associated with the aircraft brake that impact wear. Over the course of time and during braking events, the brake wear factor values are summed and a running total of that sum is kept over the life of the brake. At a point in time when the sum of weighted factors exceeds a preset threshold, an indicia is generated that service is required.

Abstract: Various embodiments of aircraft brake assembly structures are provided for achieving noise reduction during braking activity. In certain embodiments of the invention, the actual application of force to the pressure plate is regulated such that a different number of actuator pistons are used during low-energy stops than during high-energy stops. In other embodiments of the invention, the pressure plate or endplate is augmented as to surface area in some instances and as to a taper angle in others, again to achieve a desired increase in effective pressure application during low-energy stops. In other embodiments of the invention, the stator and/or rotor disks are characterized by slots to break up the propagation of noise waves.

Abstract: A long-strand carbon composite brake housing for use on aircraft is formed from a thermoplastic material carrying long-strand carbon fibers, with the composition, concentration, and orientation of the fibers being such as to optimize the strength of the resultant carrier plate, and particularly in regions subject to high stress and the like. A hydroforming technique accommodates the appropriate positioning of the thermoplastic carbon composition in the desired regions of varying concentrations, compositions, and orientations to achieve a carrier plate for aircraft brake assemblies that is lightweight while being reliable and durable in use.

Abstract: Various embodiments of aircraft brake assembly structures are provided for achieving noise reduction during braking activity. In certain embodiments of the invention, the actual application of force to the pressure plate is regulated such that a different number of actuator pistons are used during low-energy stops than during high-energy stops. In other embodiments of the invention, the pressure plate or endplate is augmented as to surface area in some instances and as to a taper angle in others, again to achieve a desired increase in effective pressure application during low-energy stops. In other embodiments of the invention, the stator and/or rotor disks are characterized by slots to break up the propagation of noise waves.

Abstract: A flexible wheel drive for aircraft onboard taxi systems is provided. In association with an aircraft wheel assembly there is provided a drive gear assembly that is adapted to be driven by a motor mounted to an aircraft. A flexible drive flange is secured about an inboard rim of the aircraft wheel assembly and a flexible ring is interconnected between the drive gear assembly and the flexible drive flange. Preferably, the flexible ring is made of a metal textile or high-temperature composite and the drive flange is of a high-strength stainless steel.

Abstract: A method of diagnosis and prognosis for various operative systems is provided so that maintenance can be efficiently and effectively scheduled and provided. The invention is applicable to a broad range of systems, but particularly to aircraft brake systems and tires. An aircraft brake may be modeled by attributing brake wear factor values to various parameters associated with the aircraft brake that impact wear. Over the course of time and during braking events, the brake wear factor values are summed and a running total of that sum is kept over the life of the brake. At a point in time when the sum of weighted factors exceeds a preset threshold, an indicia is generated that service is required.

Abstract: Various embodiments of aircraft brake assembly structures are provided for achieving noise reduction during braking activity. In certain embodiments of the invention, the actual application of force to the pressure plate is regulated such that a different number of actuator pistons are used during low-energy stops than during high-energy stops. In other embodiments of the invention, the pressure plate or endplate is augmented as to surface area in some instances and as to a taper angle in others, again to achieve a desired increase in effective pressure application during low-energy stops. In other embodiments of the invention, the stator and/or rotor disks are characterized by slots to break up the propagation of noise waves.

Abstract: A flexible wheel drive for aircraft onboard taxi systems is provided. In association with an aircraft wheel assembly there is provided a drive gear assembly that is adapted to be driven by a motor mounted to an aircraft. A flexible drive flange is secured about an inboard rim of the aircraft wheel assembly and a flexible ring is interconnected between the drive gear assembly and the flexible drive flange. Preferably, the flexible ring is made of a metal textile or high-temperature composite and the drive flange is of a high-strength stainless steel.

Abstract: An electric aircraft brake control system has a plurality of wheel and brake assemblies, each having a wheel, wheel speed transducer, brake assembly and a brake actuator. Electromechanical control units are uniquely associated with and connected to certain of the wheel and brake assemblies, and each of the electromechanical control units is provided with an antiskid system as an integral portion thereof. Brake data concentrators are provided for receiving data corresponding to various aircraft operational parameters, including brake pedal position, and provide operational signals to the electromechanical control unit as a function thereof. A controller for emergency and park braking is connected to the electromechanical actuator controllers through one of the brake data concentrators to effect emergency braking action on the brake assemblies, such emergency braking action having incident antiskid control.

Abstract: A heat shield segment includes at least one tab extending from an outboard end, the tab adapted to secure the heat shield segment against radial and axial movement. The at least one tab is received over a retaining ring positioned within a tube well of a wheel. The retaining ring is received in recesses formed in the inner surface of drive keys spaced around the interior of the tube well. The heat shield segment is secured at the inboard end by a fastener, and is spaced from the tube well by a spacer positioned between the heat shield segment and the tube well. The at least one tab of the heat shield segment allows for easy assembly and maintenance of the heat shield assembly formed by a plurality of the heat shield segments.

Abstract: A heat shield segment includes at least one tab extending from an outboard end, the tab adapted to secure the heat shield segment against radial and axial movement. The at least one tab is received over a retaining ring positioned within a tube well of a wheel. The retaining ring is received in recesses formed in the inner surface of drive keys spaced around the interior of the tube well. The heat shield segment is secured at the inboard end by a fastener, and is spaced from the tube well by a spacer positioned between the heat shield segment and the tube well. The at least one tab of the heat shield segment allows for easy assembly and maintenance of the heat shield assembly formed by a plurality of the heat shield segments.

Abstract: An electric aircraft brake control system has a plurality of wheel and brake assemblies, each having a wheel, wheel speed transducer, brake assembly and a brake actuator. Electromechanical control units are uniquely associated with and connected to certain of the wheel and brake assemblies, and each of the electromechanical control units is provided with an antiskid system as an integral portion thereof. Brake data concentrators are provided for receiving data corresponding to various aircraft operational parameters, including brake pedal position, and provide operational signals to the electromechanical control unit as a function thereof. A controller for emergency and park braking is connected to the electromechanical actuator controllers through one of the brake data concentrators to effect emergency braking action on the brake assemblies, such emergency braking action having incident antiskid control.

Abstract: An electric brake actuator and force transducer for the brake system of an aircraft is presented. A brake actuator includes a piston driven by a cylindrical nut and screw arrangement, driven by an appropriate motor of the actuator. Application of brake force results in a reactionary force that deflects the top cover of the actuator. The axial component of this deflection correlates directly with the brake force applied. A beam is interposed between this cover and a top cap, such that deflection of the beam correlates to applied brake face. Piezo-resistive devices are connected to the beam and, through a whetstone bridge, provide an electrical output signal correlating to applied brake force.

Abstract: An electric brake actuator for the brake system of an aircraft is presented. A brake actuator includes a piston driven by a cylindrical nut and screw arrangement, driven by an appropriate motor of the actuator. Application of brake force results in a reactionary force that deflects the top cover of the actuator. The axial component of this deflection correlates directly with the brake force applied. A beam is interposed between this cover and a top cap, such that deflection of the beam correlates to applied brake face. Piezo-resistive devices are connected to the beam and, through a whetstone bridge, provide an electrical output signal correlating to applied brake force.

Abstract: An electric brake actuator for the brake system of an aircraft is presented. A brake actuator includes a piston driven by a cylindrical nut and screw arrangement, driven by an appropriate motor of the actuator. Application of brake force results in a reactionary force that deflects the top cover of the actuator. The axial component of this deflection correlates directly with the brake force applied. A beam is interposed between this cover and a top cap, such that deflection of the beam correlates to applied brake face. Piezo-resistive devices are connected to the beam and, through a whetstone bridge, provide an electrical output signal correlating to applied brake force.

Abstract: A beam key and wheel assembly for aircraft brakes is presented. A beam key is pinned at one end to the aircraft wheel and is engaged proximate an opposite end to a pad on an outrigger flange of the wheel. The pad has a milled arcuate surface which is congruent with and nestingly receives a similar arcuate surface of a foot member. The foot has a channel formed therein on a side opposite the arcuate surface, the channel matingly receiving a base on a bottom surface of the beam key. A bolt passes through the beam key, foot, and pad on the outrigger flange to secure the elements together.