A gas turbine engine includes: a casing that accommodates a compressor and the like; bearings; a main lubricator including an oil mist generator that generates oil mist by mixing oil with compressed air extracted from the compressor and a first supply passage through which the oil mist is guided to the bearings; and a starting lubricator including a second supply passage through which a gas flowing out from a gas source is guided to a connection portion of the first supply passage, the connection portion being connected to the second supply passage, and an opener that starts supply of the gas from the gas source. The main lubricator supplies the oil mist to the bearings through the first supply passage by the pressure of the compressed air extracted from the compressor. When the opener starts the supply of the gas, the starting lubricator supplies the oil mist to the bearings by the pressure of the gas flowing out from the gas source.

An inner structure is within an outer structure. A shield mount of a shield is attached to the outer structure. A sleeve of the shield extends from the shield mount through an aperture in the outer structure to a distal end of the shield. The sleeve is mated with the port at the distal end through a slip joint interface where a cylindrical sleeve surface of the sleeve contacts a cylindrical port surface of a port of the inner structure. The fluid transfer tube extends from an inner tube end through a bore of the shield and at least into the port to an outer tube end. An inner coupling is disposed at the inner tube end and mated with the inner structure through a cone seal interface. An outer coupling is disposed at the outer tube end and attached to the outer structure.

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.

An aircraft engine circulation system comprises a conduit arranged in use to communicate a lubricant to and from one or more bearings of an engine. The conduits define a space which comprises a material that is selected to change phase at a predetermined temperature.

A gas turbine engine includes an engine static structure. A rotating structure is configured to rotate relative to the engine static structure. The rotating structure has a target area with first and second directions. The first direction is greater than the second direction. A lubrication system includes a nozzle having a non-circular exit aimed at the target area. The exit provides a width and a height. The width is greater than the height. The width is oriented in the first direction.

The aircraft engine can have an air-oil separator having an air-oil mixture inlet, an oil outlet, an air outlet, and a pressure relief path provided fluidly in parallel with the air-oil separator, between the air-oil mixture inlet and the air outlet, the pressure relief path can have a pressure relief valve for evacuating air-oil mixture to the exhaust duct in the event of excess pressure in the auxiliary gearbox.

A de-aerator for a lubrication system, has: a housing defining an air-oil inlet, an oil outlet, and an air outlet of the de-aerator; a rotor received within the housing and rotatable relative to the housing about a central axis, the rotor having blades distributed about the central axis and extending at least partially radially relative to the central axis, flow passages extending between the blades, the rotor having a hub circumferentially extending around the central axis and around the blades, the hub having a peripheral wall oriented radially inwardly and defining a fore opening leading to the flow passages; and a gap between the housing and the hub of the rotor, a portion of the housing received within the fore opening and axially overlapping the peripheral wall of the hub, the gap having a fore gap inlet between the portion of the housing and the peripheral wall of the hub.

An engine assembly for an aircraft including a bypass turbomachine as well as a turbomachine attachment pylon including an air-oil exchanger system arranged in an inter-ducts compartment between the flow ducts, the compartment being delimited radially on the outside by an inter-ducts cowling, the exchanger system being supplied with air from a secondary flow duct of the turbomachine delimited radially on the inside by the inter-ducts cowling, and the exchanger system being supported by a support arranged in the inter-ducts compartment, this support being mechanically connected to the attachment pylon by connecting means passing through the inter-ducts cowling.

A hydraulic fracturing plan executable by a hydraulic fracturing system to hydraulically fracture a plurality of oil and gas wells.

An oil tank filling system for filling the oil tank of a gas turbine engine. The system includes an oil tank located within the core of the engine, an engine oil filling port located on a bifurcation below the core of the engine, and an oil tank filling pipe that leads from the engine oil filling port to a tank filling port on the oil tank. The engine oil filling port is detachably connectable to an off-engine oil pump that when connected to the engine oil filling port and supplied with oil pumps oil into the engine oil filling port and through the oil tank filling pipe to the tank filling port to fill the oil tank. A method of filling the oil tank of a gas turbine engine and a gas turbine engine that includes the oil tank filling system are also disclosed.