Abstract: An auxiliary power unit for an aircraft includes a turbine engine. An inlet includes an opening and a passageway between the opening and the turbine engine. An acoustic splitter is supported within the passageway for attenuating noise within the inlet. An inlet door is movable between a closed position and a fully open position. A portion of the inlet door aligns with a part of the passageway in at least a first position and divides the passageway to deflect ice and noise in at least a second position. An air inlet and a method are also disclosed.

Abstract: An auxiliary power unit for an aircraft includes a turbine engine. An inlet includes an opening and a passageway between the opening and the turbine engine. An acoustic aplitter is supported within the passageway for attenuating noise within the inlet. An inlet door is movable between a closed position and a fully open position. A portion of the inlet door aligns with a part of the passageway in at least a first position and divides the passageway to deflect ice and noise in at least a second position. An air inlet and a method are also disclosed.

Abstract: An example lubricating transfer tube assembly includes a transfer tube having a bore extending from a fluid inlet portion to a fluid outlet portion. The transfer tube is configured to communicate a fluid through the bore between the fluid inlet portion and the fluid outlet portion within a gearbox. The transfer tube defines a spray aperture extending from the bore to an outer surface of the transfer tube. The spray aperture is configured to communicate at least some of the fluid from the bore to an area of the gearbox.

Abstract: An auxiliary power unit is composed of a gas turbine engine, a gearbox, and a gearbox driven generator. A mount bracket is mechanically attached to the gearbox. The bracket is for connecting to an aircraft strut system. The aircraft strut system connects to the aircraft structure. The mount bracket has an upper mechanical attachment point and a lower mechanical attachment point to the gearbox. The gearbox includes an oil reservoir, and the lower attachment point is beneath the oil level within the oil reservoir such that said lower attachment point will be cooled by oil in the oil reservoir.

Abstract: An auxiliary power unit includes a gearbox housing portion and a filter housing portion providing an integral housing. A filter cavity is provided in the filter housing portion. A surface circumscribes the filter cavity. A scupper includes a passage extending from the surface to an opening on an exterior surface of the integral housing. A sealing region between the scupper and the filter cavity is configured to fluidly isolate the scupper and the fuel filter cavity from one another. In one example, the filter cavity receives a fuel filter cartridge. A cap is secured to the filter housing portion and encloses the filter cavity when in a secured position.

Abstract: A gearbox for an auxiliary power unit (APU) includes features that prevent submersion of gears in lubricant in extreme attitude orientations. The gearbox includes a plurality of gears that drive various pumps, generators and/or other aircraft systems. A shield surrounds a portion of one of the plurality of gears to prevent lubricant from submerging the gear. The shield defines at least a portion of an open chamber that is at least partially surrounded by lubricant at extreme attitude orientations.

Abstract: A gearbox for use in an auxiliary power unit has a plurality of gears received within a housing. A lube pump is mounted within the housing, and delivers oil to the plurality of gears and bearings. The lube pump has an oil supply tube for supplying oil to the pump for delivery to the plurality of gears and bearings. An oil reservoir maintains a quantity of oil above a lowermost end of the inlet tube, and is shaped such that a cross-sectional area at a lower end of the inlet tube has a first cross-sectional area. Other cross-sectional areas spaced upwardly from the first cross-sectional area are greater. A ratio of the second cross-sectional area to the first cross-sectional area is less than 3.

Abstract: An auxiliary power unit is composed of a gas turbine engine, a gearbox, and a gearbox driven generator. A mount bracket is mechanically attached to the gearbox. The bracket is for connecting to an aircraft strut system. The aircraft strut system connects to the aircraft structure. The mount bracket has an upper mechanical attachment point and a lower mechanical attachment point to the gearbox. The gearbox includes an oil reservoir, and the lower attachment point is beneath the oil level within the oil reservoir such that said lower attachment point will be cooled by oil in the oil reservoir.

Abstract: A lube pump has a housing with a flange extending radially outwardly from a body of the housing. At least one rotor is received within the housing, and a shaft for powering the rotor extends away from the flange. A retention plate is positioned on an end of the flange closing the housing. A first set of bolts secure the flange to the retention plate. A second set of bolts secure the flange to the gearbox. The two sets of bolts extend in opposed directions. A gearbox including such a lube pump is also disclosed and claimed.

Abstract: A twin lubrication oil tank filling system with a single oil fill port that prevents overfilling of both a primary oil tank and a secondary oil with a gravity fill system by directing oil primarily into the secondary oil tank by means of a special oil diverter, a float valve for the secondary oil tank that closes when the oil level in the secondary tank reaches a full level to cause additional oil flow to pour into the primary oil tank and a float valve for the primary oil tank that closes when the oil level in the primary tank reaches a full level.

Abstract: An example deaerator assembly includes a deaerating member disposed within a housing. The deaerating member includes an apertured stem extending from a pedestal. The apertured stem is configured to communicate air away from a mixture of air and coolant when the mixture of air and coolant is communicated about the apertured stem.

Abstract: An example lubricating transfer tube assembly includes a transfer tube having a bore extending from a fluid inlet portion to a fluid outlet portion. The transfer tube is configured to communicate a fluid through the bore between the fluid inlet portion and the fluid outlet portion within a gearbox. The transfer tube defines a spray aperture extending from the bore to an outer surface of the transfer tube. The spray aperture is configured to communicate at least some of the fluid from the bore to an area of the gearbox.

Abstract: An example deaerator assembly includes a deaerating member disposed within a housing. The deaerating member includes an apertured stem extending from a pedestal. The apertured stem is configured to communicate air away from a mixture of air and coolant when the mixture of air and coolant is communicated about the apertured stem.

Abstract: A gearbox for use in an auxiliary power unit has a plurality of gears received within a housing. A lube pump is mounted within the housing, and delivers oil to the plurality of gears and bearings. The lube pump has an oil supply tube for supplying oil to the pump for delivery to the plurality of gears and bearings. An oil reservoir maintains a quantity of oil above a lowermost end of the inlet tube, and is shaped such that a cross-sectional area at a lower end of the inlet tube has a first cross-sectional area. Other cross-sectional areas spaced upwardly from the first cross-sectional area are greater. A ratio of the second cross-sectional area to the first cross-sectional area is less than 3.

Abstract: A lube pump has a housing with a flange extending radially outwardly from a body of the housing. At least one rotor is received within the housing, and a shaft for powering the rotor extends away from the flange. A retention plate is positioned on an end of the flange closing the housing. A first set of bolts secure the flange to the retention plate. A second set of bolts secure the flange to the gearbox. The two sets of bolts extend in opposed directions. A gearbox including such a lube pump is also disclosed and claimed.

Abstract: An auxiliary power unit includes a gearbox housing portion and a filter housing portion providing an integral housing. A filter cavity is provided in the filter housing portion. A surface circumscribes the filter cavity. A scupper includes a passage extending from the surface to an opening on an exterior surface of the integral housing. A sealing region between the scupper and the filter cavity is configured to fluidly isolate the scupper and the fuel filter cavity from one another. In one example, the filter cavity receives a fuel filter cartridge. A cap is secured to the filter housing portion and encloses the filter cavity when in a secured position.

Abstract: A gearbox for an auxiliary power unit (APU) includes features that prevent submersion of gears in lubricant in extreme attitude orientations. The gearbox includes a plurality of gears that drive various pumps, generators and/or other aircraft systems. A shield surrounds a portion of one of the plurality of gears to prevent lubricant from submerging the gear. The shield defines at least a portion of an open chamber that is at least partially surrounded by lubricant at extreme attitude orientations.

Abstract: A twin lubrication oil tank filling system with a single oil fill port that prevents overfilling of both a primary oil tank and a secondary oil with a gravity fill system by directing oil primarily into the secondary oil tank by means of a special oil diverter, a float valve for the secondary oil tank that closes when the oil level in the secondary tank reaches a full level to cause additional oil flow to pour into the primary oil tank and a float valve for the primary oil tank that closes when the oil level in the primary tank reaches a full level.