Pratt & Whitney Canada

Apparatus and methods of monitoring a lubrication system (12) of an aircraft power plant are provided. The apparatus and method can detect a human error associated with servicing an aircraft engine. The method includes sensing an actual oil level (34) in an oil tank (26) of the lubrication system (12) of the aircraft power plant, and determining that the actual oil level (34) is below a habitual replenish level (54) that is higher than a minimum operating oil level for the oil tank (26). When the actual oil level (34) is below the habitual replenish level (54) an alert is generated.

A method for controlling a variable-pitch propeller (24) of an aircraft (12) includes using a feedback controller (62, 76), operating the variable-pitch propeller (24) at a current operating condition including a current rotational speed (NPf), determining a speed error (E) between the current rotational speed (NPf) of the variable-pitch propeller (24) and a set point rotational speed (NPref) for the variable-pitch propeller (24), determining a gain (Kp, Kd) for the feedback controller (62, 76) based on a power coefficient (Cp) and an advance ratio (J) of the variable-pitch propeller (24). Using the feedback controller (62, 76), a propeller pitch command (Co) is determined based on the speed error (E) and using the gain (Kp, Kd). The pitch of the variable-pitch propeller (24) is adjusted according to the propeller pitch command (Co) to reduce the speed error (E).

An apparatus comprising a propeller (102;304) and an engine (104;302;504) configured to drive the propeller (102;304). A controller (108;306;502) is configured to control fuel flow to the engine (104;302;504) to decelerate the propeller (102;304) responsive to detection of a propeller speed exceeding a predetermined threshold.

An apparatus includes a propeller (102;304), an engine (104;302;504) configured to drive the propeller (102;304). The apparatus also includes a controller (108;306;502) configured to control fuel flow to the engine (104;302;504) responsive to the propeller (102;304) operating in a first mode of operation and to control fuel flow to the engine (104;302;504) in a second mode of operation responsive to the propeller (102;304) operating in an uncontrollable high thrust condition.

A de-aerator (103) for an aircraft power plant (10), has: a housing (108) defining an air-oil inlet (109), an oil outlet (110), and an air outlet (111), the housing (108) having a forward end (108A) and a rearward end (108B) opposite the forward end (108A), the air-oil inlet (109) defined at the forward end (108A); a rotor (115) received within the housing (108) and rotatable relative to the housing (108) about a rotation axis (A); and a shaft (116) rotatable about the rotation axis (A), the shaft (116) extending axially from a fore end (116A) at the forward end (108A) of the housing (108) to a rear end (116B) at the rearward end (108B) of the housing (108) relative to the rotation axis (A), the rotor (115) drivingly engaged to the shaft (116) at the fore end (116A) of the shaft (116), the rear end (116B) of the shaft (116) defining a coupler (116C) drivingly engageable to a power source for rotation of the shaft (116) and of the rotor (115) mounted thereto.

A de-aerator (103) has: a housing (108) defining an air-oil inlet (109), an oil outlet (110), and an air outlet (111); a rotor (115) within the housing (108) and rotatable about a rotation axis (A) and having: inner and outer rims (123A, 123B) and blades (123), passages between the blades (123) and communicating with the air-oil inlet (109); a conduit (127) extending around the rotation axis (A) and defining a central passage (125B) extending axially and communicating with the air outlet (111), the conduit (127) being radially spaced apart from the outer rim (123B) by radial passages (126) communicating with the oil outlet (110); and openings (124) located inwardly of the blades (123) and communicating with the central passage (125B), wherein one or more of: a cross-sectional area of the central passage (1258) taken on a plane transverse to the rotation axis (A) increasing in an axial direction away from the air-oil inlet (109); and the openings (124) located at least partially radially between an inner face of the conduit (127) and an outer face of the inner rim (123A).

An aircraft propulsion system is provided that includes a thermal engine (20) and a gearbox (36). The gearbox (36) includes an input shaft (46), an output shaft (48), a first epicyclic gear arrangement (42), a drive gear (44), and a first layshaft assembly (50). The first epicyclic gear arrangement (42) includes a sun gear (54), a plurality of planet gears (56), and a ring gear (60). The sun gear (54) is connected with the drive gear (44). The first layshaft assembly (50) includes a first layshaft input gear (70), a first layshaft ring engagement gear (72), and a first clutch (74). The first layshaft ring engagement gear (72) is engaged with the ring gear (60), and the first layshaft input gear (70) is engaged with the drive gear (44) and the input shaft (46). The first clutch (74) is disposable in a clutch-disengaged configuration and in a clutch-engaged configuration.

A hybrid-electric propulsion, HEP, system (20) for powering an aircraft is provided. The system (20) includes a gearbox (26), a gas turbine engine (22), and an electric motor (24). The gearbox (26) includes an input shaft (46), an output shaft (54), a drive gear (52), a first layshaft assembly (48), a second layshaft assembly (50), and a first gearbox accessory mount (56A). The gas turbine engine (22) is in drive communication with the input shaft (46) of the gearbox (26). The electric motor (24) is engaged with the first gearbox accessory mount (56A). The first layshaft, FL, assembly (48) includes a first layshaft (68), a first FL gear (64), and a second FL gear (66). The first and second FL gears (64, 66) are attached to the first layshaft (68). The first FL gear (64) is engaged with the input shaft (46) and the second FL gear (66) is engaged with the drive gear (52). The first gearbox accessory mount (56A) is in geared communication with the drive gear (52) independent of the first layshaft assembly (48).

A method for testing a material strength of a bearing inner ring (104) includes mounting the bearing inner ring (104) on a test shaft (156) to form a ring test assembly (162). The bearing inner ring (104) includes a ring material having a first coefficient of thermal expansion. The test shaft (156) includes a test shaft (156) material having a second coefficient of thermal expansion. The second coefficient of thermal expansion is greater than the first coefficient of thermal expansion. The method further includes heating the ring test assembly (162), cooling the ring test assembly (162), and testing the material strength of the bearing inner ring (104). The testing includes performing a plurality of cycles of the steps of heating the ring test assembly and cooling the ring test assembly.

Torque measurement systems for aircraft propulsion systems include a gear assembly (200) having a shaft (202) and a bearing assembly (212) configured to rotationally support the shaft (202) within a housing (208). The bearing assembly (212) includes an inner bearing raceway (218) arranged on the shaft (202), an outer bearing raceway (220) arranged on the housing (208), a rolling element (216) arranged between the bearing raceways (218) and configured to travel along a path defined between the bearing raceways (218), and a bearing cage (228) arranged between the bearing raceways (218). The rolling element (216) is configured drive rotational movement of the bearing cage (228). An axial load member (222) is arranged to apply an axial load to the outer bearing raceway (220), a rotational velocity sensor (232) is configured to measure a rotational velocity of the bearing cage (228), and a controller (242) is configured to calculate a transferred toque of the gear assembly (200) based on a detected rotational velocity of the bearing cage (228).