A system, in certain embodiments, includes a composite crosshead. The composite crosshead comprises a crosshead body made of a first composite material, wherein the first composite material comprises a first reinforcing material distributed in a first matrix material, wherein the composite crosshead is configured to move in a reciprocating motion in a machine.

An auxiliary power unit (APU) oil quantity indication system and method provides a stable and accurate oil quantity indication during startup, mission duration and shutdown. The system determines a gulp value at various stages of operation, which is combined with a raw oil quantity indication to provide an indicated oil quantity.

The present invention includes a bypass apparatus for lubricant in an unregulated pressurized gearbox including: a block including a lubricant inlet in fluid communication with a pressure relief valve, wherein the pressure relief valve diverts lubricant into the gearbox or into an oil filter, wherein lubricant is returned to the gearbox when the lubricant is cold and/or pressure at the pressure relief valve is high to reduce damage to the gearbox caused by high pressure during a cold start, and when the lubricant temperature increases and the pressure is reduced the pressure relief valve closes and lubricant enters the oil filter.

An auxiliary power unit (APU) oil quantity indication system and method provides a stable and accurate oil quantity indication during startup, mission duration and shutdown. The system determines a gulp value at various stages of operation, which is combined with a raw oil quantity indication to provide an indicated oil quantity.

An auxiliary power unit (APU) oil quantity indication system and method provides a stable and accurate oil quantity indication during startup, mission duration and shutdown. The system determines a gulp value at various stages of operation, which is combined with a raw oil quantity indication to provide an indicated oil quantity.

A disclosed lubrication system for a turbofan engine includes a pump for driving lubricant through a lubrication circuit, at least one sensor generating a signal indicative of an engine operating condition and at least one valve for controlling a flow of lubricant through the lubrication circuit. A controller controls operation of the valve to vary the flow of lubricant based on the engine operating condition to maintain lubricant flow within predefined operating limits.

A lubricant supported electric motor includes a stator presenting an stator raceway, and a rotor movable relative to the stator and presenting a rotor raceway disposed in spaced relationship with the stator raceway to define a gap therebetween. A lubricant is disposed in the gap for supporting the rotor relative to the stator. The stator defines at least one hydrostatic support chamber disposed in radially recessed relationship relative to the stator raceway and in fluid communication with the gap. The stator also defines a passageway disposed in fluid communication with the at least one hydrostatic support chamber for providing lubricant to the at least one hydrostatic support chamber and the gap. A flow restriction mechanism is disposed in fluid communication with the passageway for controlling and balancing a supply and pressure of the lubricant in the hydrostatic support chamber.

A lubricant supported electric motor includes a stator presenting an stator raceway, and a rotor movable relative to the stator and presenting a rotor raceway disposed in spaced relationship with the stator raceway to define a gap therebetween. A lubricant is disposed in the gap for supporting the rotor relative to the stator. The stator defines at least one hydrostatic support chamber disposed in radially recessed relationship relative to the stator raceway and in fluid communication with the gap. The stator also defines a passageway disposed in fluid communication with the at least one hydrostatic support chamber for providing lubricant to the at least one hydrostatic support chamber and the gap. A flow restriction mechanism is disposed in fluid communication with the passageway for controlling and balancing a supply and pressure of the lubricant in the hydrostatic support chamber.

A lubrication system for a gas turbine engine, the system comprising: a gearbox, the gearbox comprising a sump; an oil tank; a primary gearbox lubrication system configured to pump oil from the oil tank to lubricate the gearbox with a gearbox primary feed; a secondary gearbox lubrication system, configured to lubricate the gearbox with oil from the sump when the oil level in the sump reaches a predetermined level; wherein the system is configured to increase the oil level in the sump to at least the predetermined level in response to a failure of the primary gearbox lubrication system.

A lubrication system for a gas turbine engine, the system comprising: a gearbox, the gearbox comprising a sump; an oil tank; a primary gearbox lubrication system configured to pump oil from the oil tank to lubricate the gearbox with a gearbox primary feed; a secondary gearbox lubrication system, configured to lubricate the gearbox with oil from the sump when the oil level in the sump reaches a predetermined level; wherein the system is configured to increase the oil level in the sump to at least the predetermined level in response to a failure of the primary gearbox lubrication system.