An oil supply system and a method for operating the same to provide oil to a gas turbine engine in a variety of harsh operating conditions is provided. The oil supply system includes a main oil tank and an auxiliary oil tank which share oil through a tank sharing valve that may be closed if a depressurization event occurs in the main oil tank. The oil supply system further includes an auxiliary supply conduit and an auxiliary oil pump for providing oil to the gas turbine engine in the event of main oil tank depressurization or in negative gravity conditions where the oil within the auxiliary oil tank rises to the top of the tank and uncovers the oil pump supply.

Oil system for a turbomachine, making it possible to continue the supply of oil to the pieces of equipment of the turbomachine in case of occurrence of a fire within the turbomachine, including an oil circuit, at least one oil-consuming piece of equipment, supplied by the oil circuit, a pumping unit, including at least one speed-pilotable electrically driven pump, supplying the oil circuit, and an electronic control unit, configured to pilot the electrically driven pump, wherein the electronic control unit includes two separate logics of piloting the electrically driven pump, and wherein the electronic control unit is configured to pilot the electrically driven pump according to the first logic by default and to switch to the second logic in case of receipt of a signal representative of the presence of a fire or of an overheating.

According to one embodiment, a rotorcraft includes a body, a rotor blade, a drive system that can be operated to rotate the rotor blade, and an emergency valve control unit. The drive system contains a first gearbox assembly, a second gearbox assembly, a first lubrication system that can deliver lubricant to the first gearbox assembly, and a second lubrication system that can deliver lubricant to the second gearbox assembly. The drive system also contains an emergency valve that can be opened to deliver lubricant from the first lubrication system to the second gearbox assembly. The emergency valve control unit can instruct the emergency valve to open.

A dual circuit lubrication device for lubricating a mechanical system, the lubrication device being provided with two independent lubrication circuits and a tank that is common to both lubrication circuits and that contains a lubrication liquid. A first lubrication circuit has two first suction points for sucking in the lubrication liquid and situated inside the tank, and a second lubrication circuit includes a second suction point for sucking in the lubrication liquid and situated inside the tank. The dual circuit lubrication device has means for detecting the lubrication liquid passing below a limit depth in the tank, which means are formed by a high first suction point situated at the level of the limit depth, the second suction point being situated below the limit depth, and a low first suction point being below the second suction point.

A method for monitoring a fluid system for lubricating a mechanical system. The fluid system comprises a spraying circuit connected to a main fluid circuit and to a back-up fluid circuit. The back-up fluid circuit comprises a back-up check valve closed in a nominal operating mode. The method comprises a monitoring phase comprising the generation of a first alert in the presence of the detection of a malfunction making the main fluid circuit inoperative and the back-up check valve in an open state and the generation of a second alert different from the first alert in the presence a malfunction and the back-up check valve in a closed state.

A method (500) and apparatus (50, 60) for lubrication of a gearbox (30) of an aircraft engine comprise provision (502) of oil to the gearbox (30) through a primary oil system (50) driven by a core (11) of the engine (10) in normal conditions; detection (504) of windmilling conditions and/or failure of the primary oil system (50); and in response to the detected condition or failure, activation (506) of an electric pump (61) of an auxiliary oil system (60), to provide oil to the gearbox (30).

An oil supply system and a method for operating the same to provide oil to a gas turbine engine in a variety of harsh operating conditions is provided. The oil supply system includes a main oil tank and an auxiliary oil tank which share oil through a tank sharing valve that may be closed if a depressurization event occurs in the main oil tank. The oil supply system further includes an auxiliary supply conduit and an auxiliary oil pump for providing oil to the gas turbine engine in the event of main oil tank depressurization or in negative gravity conditions where the oil within the auxiliary oil tank rises to the top of the tank and uncovers the oil pump supply.

An autofill shutoff valve includes a valve body mounted to a lubricant reservoir and secured to a fill tube extending into the reservoir. The autofill shutoff valve has a valve stem extending through the valve body and into the lubricant reservoir. The valve stem is actuated by a plate disposed within the reservoir from a first position, wherein lubricant flows from a lubricant inlet to a lubricant outlet through the valve body, to a second position, wherein the valve stem blocks the flow of lubricant through the valve body. The autofill shutoff valve provides lubricant directly to the reservoir, thereby eliminating external plumbing and the autofill shutoff valve also prevents overfill of the reservoir by cutting off the flow when the reservoir is full.

A vent valve for an actuator disposed in a lubricant reservoir includes a bore extending through the plate, a seal disposed within the bore proximate a top surface of the plate, a retaining member extending about a lower opening of the bore, and a ball disposed within the bore between the seal and the retaining member. The vent valve is configured to allow air to pass from a lower portion of a lubricant reservoir as lubricant fills the lower portion. The vent valve also allows air to pass to the lower portion of the lubricant reservoir as lubricant is dispensed from the reservoir. The vent valve closes when the lubricant level reaches the vent valve, thereby preventing lubricant from flowing through the vent valve. The sealed vent valve allows the actuator to rise in response to a rising lubricant level.

A centerfill assembly for a lubricant reservoir includes a hollow tube for receiving lubricant from the top of the reservoir and loading the lubricant into the reservoir near the bottom of the reservoir. Loading the lubricant near the bottom of the reservoir introduces lubricant near where the stirring paddles mix the lubricant and near where the lubricant is loaded to the lubricant pump. Adding the lubricant near where the pumps load and near the stirring paddles helps to eliminate air pockets in the lubricant. In addition, having the centerfill rod minimizes exterior plumbing and allows for the mounting of valves on the fill line.