Abstract: A method of and tool for positionally aligning a gearbox of a gas turbine engine is provided. The method includes: providing an alignment tool that includes a plurality of probe pins and a support flange; attaching the alignment tool to an engine case of the gas turbine engine; engaging the gearbox with the engine case; positionally aligning the gearbox by contacting a first surface of the gearbox with a first probe pin of the plurality of probe pins, and contacting a second surface of the gearbox with a second probe pin of the plurality of probe pins; and securing the gearbox to the engine case while the first probe pin is in contact with the first surface of the gearbox and the second probe pin is in contact with the second surface of the gearbox.

Abstract: A lubrication system includes a first rotating shaft and a second rotating shaft. The first rotating shaft and the second rotating shaft are separated by a flowpath. The flowpath includes a fluid. The fluid is directed towards an outer surface of the first rotating shaft. The fluid thereafter moves towards the outer surface of a second rotating shaft. The seconds structure includes a recess configured to collect the fluid. The outer surface may include a protrusion. The protrusion is configured to direct fluid from the outer surface to the recess.

Abstract: An impeller rotor includes a plurality of fluid circuits arranged circumferentially about an axis within the impeller rotor. Each of the fluid circuits includes a first outlet passage, a second outlet passage and an inlet passage fluidly coupled to the first outlet passage and the second outlet passage in parallel. A seal runner includes a bore, a sidewall and a rim. The bore is fluidly coupled to the first outlet passage of each of the fluid circuits. The rim projects radially out from the sidewall to an outer end of the rim. The rim is seated in a recess in the impeller rotor. The rim includes a flat disposed at the outer end of the rim. The flat of the rim is configured to engage a flat of the impeller rotor to rotationally fix the seal runner to the impeller rotor.

Abstract: A shaft assembly for a gas turbine engine including an outer shaft, an inner shaft, a lock nut, a locking shaft, and a washer. The outer shaft includes a bore extending between first and second ends. A portion of the inner shaft extends within the bore of the outer shaft. The lock nut is secured to the inner shaft proximate a second axial end of the inner shaft. The locking shaft includes a body portion extending between a coupling end and a retaining end. The locking shaft is disposed within the bore, with the coupling end engageable with an end of the lock nut. A washer is engageable with the retaining end and the outer shaft second end. In the assembled state, the locking shaft prevents rotation of the lock nut.

Abstract: An engine includes an engine oil system. The engine oil system includes a pump assembly forming a portion of an oil flow path. The pump assembly includes a drive shaft, a plurality of pumps, and a pump housing. The drive shaft extends along a rotational axis. The plurality of pumps are arranged axially along the rotational axis. Each of the plurality of pumps includes a pump rotor coupled with the drive shaft. The pump housing extends along the rotational axis between a first housing end and a second housing end. The pump housing circumscribes and houses the drive shaft and the plurality of pumps between the first housing end and the second housing end. The pump housing includes a plurality of housing body portions axially stacked along the rotational axis to form the pump housing. The plurality of housing body portions collectively form an internal oil passage through the pump housing.

Abstract: A gas turbine engine is provided that includes a compressor, a turbine, an engine shaft, a gearbox, and a tower shaft assembly. The engine shaft is engaged with the compressor and the turbine. The tower shaft assembly is in drive engagement with the engine shaft and the gearbox. The tower shaft assembly includes a tower shaft, a first bearing, and a first gear. The tower shaft extends axially along a rotational axis between a first and second ends. The tower shaft has a support shoulder having a non-circular configuration. The first bearing is engaged with the support shoulder of the tower shaft. The first bearing has roller elements and an inner ring engaged with the roller elements. The first gear is engaged with the tower shaft and the first bearing, and is configured for engagement with the gearbox.

Abstract: An engine includes an engine rotational assembly and an engine oil system. The engine rotational assembly includes an engine shaft and a rotor. The engine rotational assembly is rotatable about a first rotational axis. The engine oil system includes a pump assembly including a drive shaft, a pump, and a pump housing. The drive shaft is coupled with the engine shaft. The drive shaft extends along a second rotational axis between and to a first shaft end and a second shaft end. The drive shaft includes a hand crank pad at the second shaft end. The hand crank pad includes a rotational drive member. The pump includes a pump rotor coupled with the drive shaft. The pump housing extends along the second rotational axis between a first housing end and a second housing end. The second housing end forms an opening at the hand crank pad.

Abstract: A method of and tool for positionally aligning a gearbox of a gas turbine engine is provided. The method includes: providing an alignment tool that includes a plurality of probe pins and a support flange; attaching the alignment tool to an engine case of the gas turbine engine; engaging the gearbox with the engine case; positionally aligning the gearbox by contacting a first surface of the gearbox with a first probe pin of the plurality of probe pins, and contacting a second surface of the gearbox with a second probe pin of the plurality of probe pins; and securing the gearbox to the engine case while the first probe pin is in contact with the first surface of the gearbox and the second probe pin is in contact with the second surface of the gearbox.

Abstract: An engine oil system includes an oil tank and a scavenge pump assembly. The scavenge pump assembly includes a drive shaft, a plurality of scavenge pumps, and a scavenge return manifold. Each of the plurality of scavenge pumps includes a pump rotor coupled with the drive shaft. The scavenge return manifold includes a manifold body forming a common outlet passage and a plurality of inlet passages of the scavenge return manifold. The common outlet passage includes a manifold outlet of the scavenge return manifold connected in fluid communication with the oil tank. Each of the plurality of inlet passages includes a manifold inlet of the scavenge return manifold connected in fluid communication with a respective one of the plurality of scavenge pumps. Each of the plurality of inlet passages extends in an oblique direction from the manifold inlet to the common outlet passage.

Abstract: A gas turbine engine is provided that includes a compressor, a turbine, and engine shaft, a gearbox, and a tower shaft assembly. The engine shaft is engaged with the compressor and the turbine. The tower shaft assembly is in drive engagement between the engine shaft and the gearbox. The tower shaft assembly includes a tower shaft, a first bearing, and a first gear. The tower shaft extends axially along a rotational axis. The first bearing is engaged with the tower shaft. The first bearing has a plurality of roller elements and an inner ring engaged with the roller elements. The first gear (FG) is engaged with the tower shaft and extends axially between a FG first and second axial end surfaces. A first interference fit exists between the first gear and the inner ring of the first bearing. The first gear is configured for engagement with the gearbox.

Abstract: An apparatus for an aircraft powerplant includes an impeller rotor and a seal runner. The impeller rotor includes a plurality of fluid circuits. Each of the fluid circuits includes a first outlet passage, a second outlet passage and an inlet passage fluidly coupled to the first outlet passage and the second outlet passage in parallel. The seal runner includes a bore, an inner guide surface and an outer land surface. The seal runner extends circumferentially about the axis and radially between the inner guide surface and the outer land surface. The bore is fluidly coupled to the first outlet passage of each fluid circuit. The inner guide surface forms a radial outer peripheral boundary of the bore. The inner guide surface radially diverges away from the axis as the inner guide surface extends axially away from the impeller rotor and to a distal end of the seal runner.

Abstract: An assembly includes a rotating seal land, a seal element, a stationary seal support and a mating plate. The seal element axially overlaps, circumscribes and radially sealingly engages the rotating seal land. The stationary seal support axially overlaps and circumscribes the rotating seal land and the seal element. The stationary seal support includes a support notch, a support shoulder, a support inner interior surface and a support outer interior surface. The support notch projects axially into the stationary seal support from a distal end of the stationary seal support to the support shoulder. The support notch projects radially outward away from an axis into the stationary seal support from the support inner interior surface to the support outer interior surface. The mating plate is seated in the support notch and mounted to the stationary seal support. The mating plate axially contacts the support shoulder and the seal element.

Abstract: An oil filler assembly, has: a filler tube extending from a bottom end to a top end; a non-return valve having a tube side and a tank side; a cap assembly including a cap removably secured to the filler tube and a dipstick projecting from the cap; a vent having an inlet connected to the tank side and an outlet connected to the tube side, the vent defining a flow path bypassing the non-return valve; and a safety valve connected to the vent and having an open configuration in which fluid flow is permitted and a closed configuration in which fluid flow is prevented, the safety valve being engageable by the cap assembly to bias the safety valve in the open configuration when the cap is secured to the top end, the safety valve being in the closed configuration when the cap assembly is detached from the top end.

Abstract: An oil filler assembly for an aircraft engine, has: a filler tube extending from a bottom end to a top end; a valve having a tube side fluidly connected to the filler tube and a tank side; a cap removably secured to the top end; a dipstick secured to the cap and extending into the filler tube; and a piston secured to the dipstick, the piston having: a sealing configuration in which the piston sealingly engages the filler tube to fluidly disconnect the top end from the valve, the piston being in the sealing configuration when the cap is secured to the top end of the filler tube; and a venting configuration in which the piston permits fluid communication between the top end and the valve, the piston being in the venting configuration when the cap is moved away from the top end of the filler tube.

Abstract: A method of monitoring a sealing component of a gas turbine engine, comprising: collecting oil leaked from the component; detecting a volume of the collected oil upstream of an oil return path of the gas turbine engine; and signalling for inspection of the component when the volume of the collected oil exceeds a threshold volume. Also disclosed is an oil leakage monitoring system for a gas turbine engine, comprising: one or more sealing components to be lubricated by oil; a valve downstream of the one or more components and fluidly connected to an oil system; a reservoir downstream of the one or more components to collect oil, the reservoir upstream of the valve; and a volume measurement device configured to detect the oil collected in the reservoir, and to signal for inspection of the one or more components when the oil collected in the reservoir exceeds a threshold volume.

Abstract: The contact seal assembly for a shaft of a gas turbine engine includes a carbon seal mounted in a fixed position within a seal housing, and an annular seal runner adapted to be connected to the shaft of the gas turbine engine and rotatable relative to the carbon ring segments. The seal runner is disposed adjacent to and radially inwardly from the carbon ring segments to form a contact interface between the seal runner and the carbon ring segments which forms a substantially fluid tight seal. The seal runner includes a coolant scoop disposed in a cavity defined by the seal housing, a first slinger disposed between the coolant scoop and the contact interface, a second slinger disposed between the first slinger and the contact interface, and a coolant collector groove disposed between the first slinger and the second slinger.

Abstract: A method of monitoring a sealing component of a gas turbine engine, comprising: collecting oil leaked from the component; detecting a volume of the collected oil upstream of an oil return path of the gas turbine engine; and signalling for inspection of the component when the volume of the collected oil exceeds a threshold volume. Also disclosed is an oil leakage monitoring system for a gas turbine engine, comprising: one or more sealing components to be lubricated by oil; a valve downstream of the one or more components and fluidly connected to an oil system; a reservoir downstream of the one or more components to collect oil, the reservoir upstream of the valve; and a volume measurement device configured to detect the oil collected in the reservoir, and to signal for inspection of the one or more components when the oil collected in the reservoir exceeds a threshold volume.

Abstract: There is disclosed an aircraft engine having: an engine shaft; a first transmission shaft in driving engagement with the engine shaft and a second transmission shaft concentric with the first transmission shaft and in driving engagement with the first transmission shaft, the second transmission shaft drivingly engageable to an engine accessory, the first and second transmission shafts rotatable about an axis; and at least two axially spaced apart annular ring seals disposed radially between the first and second transmission shafts, the at least two annular ring seals biased against both of the first and second transmission shafts.

Abstract: The contact seal assembly for a shaft of a gas turbine engine includes a carbon seal mounted in a fixed position within a seal housing, and an annular seal runner adapted to be connected to the shaft of the gas turbine engine and rotatable relative to the carbon ring segments. The seal runner is disposed adjacent to and radially inwardly from the carbon ring segments to form a contact interface between the seal runner and the carbon ring segments which forms a substantially fluid tight seal. The seal runner includes a coolant scoop disposed in a cavity defined by the seal housing, a first slinger disposed between the coolant scoop and the contact interface, a second slinger disposed between the first slinger and the contact interface, and a coolant collector groove disposed between the first slinger and the second slinger.

Abstract: There is disclosed an aircraft engine having: an engine shaft; a first transmission shaft in driving engagement with the engine shaft and a second transmission shaft concentric with the first transmission shaft and in driving engagement with the first transmission shaft, the second transmission shaft drivingly engageable to an engine accessory, the first and second transmission shafts rotatable about an axis; and at least two axially spaced apart annular ring seals disposed radially between the first and second transmission shafts, the at least two annular ring seals biased against both of the first and second transmission shafts.