A method and system for diagnosing a condition of an air-breathing aircraft engine are described. The method comprises obtaining a sample of lubricating fluid from the engine, filtering the sample to obtain a plurality of particles from the lubricating fluid, obtaining chemical composition data for the plurality of particles, determining a quantity of volcanic ash in the lubricating fluid by considering each one of the particles as composed partially of volcanic ash and partially of at least one other material and determining a first percentage of surface area of the particles covered by the volcanic ash and a second percentage of the surface area of the particles covered by the at least one other material, the volcanic ash having associated thereto a predetermined chemical composition, and diagnosing a condition of the engine based on the quantity of volcanic ash found in the lubricating fluid.

A method and a sampling tool for collecting particles from lubrication fluid of an engine are disclosed. The particles collected may be used to conduct analysis to diagnose a condition of the engine. The tool can be detachably connectable to a lubrication system of the engine. The tool comprises an inlet for receiving lubrication fluid from the lubrication system of the engine, a filter and a pump configured to induce a flow of the lubrication fluid through the filter.

A hybrid propulsion system includes a heat engine configured to drive a heat engine shaft. An electric motor configured to drive a motor shaft. A transmission system is connected to receive rotational input power from each of the heat engine shaft and the motor shaft and to convert the rotation input power to output power. A first lubrication/coolant system is connected for circulating a first lubricant/coolant fluid through the heat engine. A second lubricant/coolant system in fluid isolation from the first lubrication/coolant system is connected for circulating a second lubricant/coolant fluid through the electric motor.

The de-aerator can be used to separate air from oil in an aircraft engine lubrication system. The de-aerator can include a swirler cavity extending circumferentially around axis and axially between a proximal wall and a distal wall, a separation path dividing within the swirler cavity into a radially outer oil segment leading to an oil outlet and a radially inner air segment leading to an air outlet, and a swirling conduit portion having a length turning around the axis upstream of an opening in the proximal wall along the separation path.

A system and method for predicting a remaining oil life of oil in a gearbox of an air turbine starter of a vehicle. The method includes generating a temperature data, generating an environmental data set by an environmental sensor, predicting a remaining oil life based on the temperature data set and the environmental data set and scheduling a maintenance event in response to the prediction of the remaining oil life.

An air/oil separator is provided. The air/oil separator includes an oil manifold having a first air/oil inlet and a second air/oil inlet; a first separation chamber in communication with the first air/oil inlet; and a second separation chamber separate from the first separation chamber, the second separation chamber in communication with the second air/oil inlet.

An assembly is provided for a fluid system. This fluid system assembly includes a fluid conduit and a plug. The fluid conduit has an internal bore. The internal bore is configured as or otherwise includes a smooth-walled internal bore. The plug includes a protrusion and a head. The protrusion is connected to the head. The protrusion projects axially along an axial centerline partially into the smooth-walled internal bore to a distal end of the plug. The head is seated against the fluid conduit. The head seals an opening in the fluid conduit to the internal bore.

An oil distribution system including a shaft assembly, bearing assembly and mounting assembly is disclosed. The shaft assembly includes a shaft with an inner shaft. A pocket is defined between the shaft and the inner shaft. A ringed lattice containing oil is secured within the pocket, melting of the ringed lattice releases the oil. The shaft includes shaft slots to usher oil from the pocket towards the bearing assembly. The bearing assembly includes an inner and outer race. The inner and outer race each include axial slots and radial slots. The axial slots of the inner race align with the shaft slots to allow oil to flood the inner race. The mounting assembly includes a bearing support having bearing support slots to receive a stringed lattice. Oil from the bearing support flows into the outer race when the axial slots of the outer race align with the bearing support slots.

A method of cooling an aircraft power plant having a combustion engine is disclosed. The method comprises in a first operating mode, inducing a cooling air flow through a heat exchanger in an air conduit via a flow inducing device fluidly connected to the air conduit, the heat exchanger connected in heat exchange relationship with the power plant of the aircraft. The method comprises, in a second operating mode, bypassing the cooling air flow from the flow inducing device via a selectively closable air outlet of the air conduit downstream of the heat exchanger. A cooling system for an aircraft power plant is also disclosed.

An oil distribution system including a shaft assembly, bearing assembly and mounting assembly is disclosed. The shaft assembly includes a shaft with an inner shaft. A pocket is defined between the shaft and the inner shaft. A ringed lattice containing oil is secured within the pocket, melting of the ringed lattice releases the oil. The shaft includes shaft slots to usher oil from the pocket towards the bearing assembly. The bearing assembly includes an inner and outer race. The inner and outer race each include axial slots and radial slots. The axial slots of the inner race align with the shaft slots to allow oil to flood the inner race. The mounting assembly includes a bearing support having bearing support slots to receive a stringed lattice. Oil from the bearing support flows into the outer race when the axial slots of the outer race align with the bearing support slots.