Abstract: An aircraft control system may include an engine control subsystem, a flight control subsystem, a processor, and a tangible, non-transitory memory. The tangible, non-transitory memory may be configured to communicate with the processor, and the tangible, non-transitory memory may have instructions stored thereon that, in response to execution by the processor, cause the aircraft control system to perform various operations. The various operations may include controlling, by the processor, the engine control subsystem and controlling, by the processor, the flight control subsystem. That is, a single processor (or a single set of processors) may control both the engine control subsystem and the flight control subsystem.

Abstract: An air to air heat exchanger is provided including a core having a plurality of alternately stacked first layers and second layers. Each first layer includes a plurality of first modules having corrugated fins that define a plurality of first fluid flow paths. The first modules are aligned to fluidly couple the first fluid flow paths. Each second layer includes at least one second module having corrugated fins that define a plurality of second fluid flow paths. At least one second layer includes a third module having a plurality of corrugated fins that define a plurality of third fluid flow paths. The third module is arranged such that the third fluid flow paths are parallel to the second fluid flow paths. A number of corrugated fins formed in the third module is less than a number of corrugated fins formed in the second module.

Abstract: In at least one aspect of this disclosure, a shut off valve for an ecology fuel return system can include an inlet for receiving a fluid, an outlet for effusing the fluid, and a valve member configured to move between an open position such that the valve member allows fluid to effuse from the outlet and a closed position such that the valve member prevents fluid from effusing from the outlet. The valve member can include a pressure deflector configured to prevent fluid flow from biasing the valve member toward the closed position.

Abstract: A multi-disk brake system comprises an electrical generator disposed therein. The electrical generator is configured to convert mechanical energy to electrical energy. The mechanical energy may be generated during a braking event of the multi-disk brake system. The electric generator may power various electrical components on the aircraft or store the electrical energy in a capacitor bank. The electric generator may also act as a motor and/or power a landing gear in a motor configuration.

Abstract: A brake system may comprise a hydraulic brake system or a hybrid brake system. The hydraulic brake system may include an inner axle disposed in an inner axle housing. The inner axle housing may include a working fluid therein. The inner axle may comprise a plurality of paddles extending radially from the inner axle. The working fluid may be pressurized and/or create friction with the plurality of paddles. The pressurized working fluid may impede a free rotation of the plurality of paddles.

Abstract: A rotary actuator including: an electric motor including: a left shaft projecting out towards a left-hand side; a left motor operably connected to the left shaft; a right shaft projecting out towards a right-hand side; and a right motor operably connected to the right shaft; an actuator housing operably connected to the right shaft; a left outer actuator shaft operably connected to the actuator housing; a left inner actuator shaft operably connected to the left shaft; and an output gearbox including: a ring gear rigidly connected to the left outer actuator shaft; a center gear located within the ring gear, the center gear being operably connected to the left inner actuator shaft; a planetary gear interposed between the ring gear and center gear, the planetary gear meshing with the ring gear and center gear; and an actuator stub operably connected to the planetary gear.

Abstract: A starter air valve has a valve member and an actuator. A rotary spool valve has a rotatable valve body and an outer housing to selectively provide three modes of operation for the starter air valve. A first mode of operation connects air through the rotatable valve body to communicate with an actuator control, and to receive air back from the actuator control. The rotatable valve body then communicates the air to the actuator. In a second mode the rotatable valve body blocks communication between the actuator control and the actuator, and delivers air through a variable area port in a wall of the rotatable valve body to bypass the valve member. In a third mode the rotatable valve body blocks communication between the actuator and the actuator control, and connects air to the actuator without having passed to the actuator control. A starter air system is also disclosed.

Abstract: A starter air valve (SAV) system can include a pressure actuated SAV actuator configured to be operatively connected to a SAV and a first pressure valve configured to selectively allow pressure from a pressure source to the SAV actuator when in fluid communication with the SAV actuator. The first pressure valve can be a pulse-width modulation solenoid valve configured to provide a duty cycle of pressure from the pressure source to the SAV actuator.

Abstract: A gas turbine engine/generator arrangement including a generator, a low-pressure spool operably connected to the generator, a high-pressure spool operably connected to the low-pressure spool, and an electric motor. The electric motor is mechanically connected to the high-pressure spool and is electrically connected to the generator to communicate mechanical rotation between the electric motor and the high-pressure spool. Auxiliary power units and methods of generating electric power are also described.

Abstract: Apparatus and associated methods relate to equalizing wearing of a plurality of electrical power generators of an aircraft. Such equalization is achieved by logging operating conditions of at least a powered subset of the electrical power generators and then comparing of the logged operating conditions of each of the plurality of electrical power generators. Based on the comparison of the logged operating conditions, one of the plurality of electrical power generators for use the aircraft is recommended. A signal indicative of the recommended one of the electrical power generators determined is then generated.

Abstract: A pressure vessel includes a first container and a second container surrounding the first container and including a fluid port. The pressure vessel further includes a barrier space extending between the first container and the second container and a leak detection mechanism connected to the fluid port on the second container that is configured to detect a leak in the pressure vessel.

Abstract: A bearing carrier is provided. The bearing carrier including: a bearing body of a first material having a shaft-receiving aperture and a bridge land with a finger cut to channel fluid pressurized by intermeshing of gears rotatably supported by the bearing carrier into an outlet defined by a housing enveloping the bearing carrier, wherein the bearing body includes a bearing face configured to be in a facing spaced relationship with the gears, wherein the bearing face includes a second material integral with the first material, wherein at least one of the first material and the second material define a portion of the bearing face of the bearing body extending about the shaft-receiving aperture, the portion of the bearing face excluding the bridgeland.

Abstract: An engine fuel system is disclosed for managing drainage of fuel in response to an engine shut-down condition. For normal operation, a piston of a piston assembly is maintained in a first position by pressurized fuel in a volume on a first side of the piston. In response to engine shut-down, pressure is removed from the first side of the piston and fuel in the volume on the first side of the piston is drained into a return conduit that is part of the fuel system's thermal management system. Displacement of the piston in response to removal of pressure on the first side of the piston creates a volume on a second side of the piston for drainage of fuel from a fuel manifold.

Abstract: A fuel-based thermal management system may comprise a heat exchanger configured to thermally couple a fluid and a fuel. A controller may be configured to modulate a flow of the fluid to the heat exchanger. A tangible, non-transitory memory may be configured to communicate with the controller. The controller may determine a temperature of the fluid, estimate a dissolved oxygen concentration in the fuel using a first fuel temperature, a flight cycle time, and at least one of an altitude measurement or a ambient pressure measurement, and modulate the flow of the fluid to the heat exchanger based on the dissolved oxygen concentration.

Abstract: An apparatus is provided. The apparatus includes a heat exchanger providing heat transfer between a first medium and a second medium. The apparatus also includes a movable aperture integrated onto a face of the heat exchanger and regulating a flow of the first medium based on a position of the movable aperture. The apparatus further includes an actuator controlling the position of the movable aperture.

Abstract: A starter air valve (SAV) system includes a pressure actuated SAV actuator configured to be operatively connected to a SAV, a first pressure valve configured to selectively allow pressure from a pressure source to the SAV actuator when in fluid communication with the SAV actuator, and a second pressure valve configured to selectively allow pressure from the pressure source to the SAV actuator when in fluid communication with the SAV actuator. A manual override (MOR) valve selector is disposed between the first pressure valve, the second pressure valve, and the SAV actuator, the MOR valve selector configured to selectively fluidly connect the first pressure valve and the SAV actuator in a first position and to fluidly connect the second pressure valve and the SAV actuator in a second position.

Abstract: An objective-driven system for blade tip clearance control may comprise a BOAS and a controller in operable communication with the BOAS. A tangible, non-transitory memory may be configured to communicate with the controller, the tangible, non-transitory memory may have instructions stored thereon that, in response to execution by the controller, cause the controller to perform operations comprising receiving an operating objective definition, and modulating a location of the BOAS using an optimization loop comprising the operating objective definition, input vector variables, and output vector variables driven by the input vector variables.

Abstract: A starter air valve comprising a housing comprising an inlet at a first end and an outlet at a second end opposite the first end, the inlet being fluidly connected to the outlet through a fluid pathway; a valve injected into the fluid pathway dividing the fluid pathway into a first chamber and second chamber, the valve in operation adjusts fluid flow through fluid pathway; an actuator operably connected to the valve; a solenoid in variable electrical connection with the actuator; and a rotary spool valve fluidly connected to the first chamber, the rotary spool valve operable to rotate to at least one of a normal start position, a full manual override position, and a plurality of partial manual override positions, wherein the rotary spool valve is in variable fluid connection with the actuator, wherein the solenoid is in variable electrical connection with the actuator through the rotary spool valve.

Abstract: A rotary propulsion system includes a fan arranged along a rotation axis, an electric motor having windings and a permanent magnet arranged along the rotation axis and operatively connected to the fan, and a reduction gear set. The reduction gear set extends about the rotation axis and couples the electric motor to the fan. The permanent magnet is rotatable relative to the windings and the fan to rotate the fan using the electric motor at a rotational speed that is lower than a rotational speed of the permanent magnet. Aircraft and methods of propelling aircraft are also described.

Abstract: A jam-tolerant electromechanical linear actuator having a contra-rotating axial flux permanent magnet (PM) motor having a first and second rotor shafts in a motor housing. The actuator also includes a first speed reduction mechanism operably coupled to the first rotor shaft and a second speed reduction mechanism operably coupled to the second rotor shaft; a first output shaft operably coupled to a output of the first speed reduction mechanism and a second output shaft operably coupled to an output of the second speed reduction mechanism. The actuator also includes a housing enclosing the PM motor, first speed reduction mechanism and second speed reduction mechanism and a slide mechanism operably coupled to the housing. The slide mechanism permit the housing to slide when the motor housing is fixed to the housing or the motor housing to slide with respect to the housing when the housing is held fixed.