A fuel system is provided for an aircraft having a fuel source. The fuel system includes a fuel oxygen reduction unit defining a liquid fuel supply path, a stripping gas supply path, a liquid fuel outlet path, and a stripping gas return path, wherein the stripping gas return path is in airflow communication with the fuel source.

A fuel system for an aircraft can include one or more airframe fuel lines configured to transfer fuel from one or more fuel tanks to an engine, one or more engine fuel pumps in fluid communication with the one or more airframe fuel lines and configured to pressurize fuel from a main stage boost pressure to a combustor pressure to be injected into a combustor of an engine, one or more airframe fuel pumps configured to pressurize fuel within the one or more airframe fuel lines to the main stage boost pressure used by the engine fuel pump. For example, the main stage boost pressure can be about 250 psi.

A fuel system for an aircraft can include one or more airframe fuel lines configured to transfer fuel from one or more fuel tanks to an engine, one or more engine fuel pumps in fluid communication with the one or more airframe fuel lines and configured to pressurize fuel from a main stage boost pressure to a combustor pressure to be injected into a combustor of an engine, one or more airframe fuel pumps configured to pressurize fuel within the one or more airframe fuel lines to the main stage boost pressure used by the engine fuel pump. For example, the main stage boost pressure can be about 250 psi.

A system and method of controlling a fuel system on an aircraft includes selectively supplying fuel from either a main fuel tank or at least one wing fuel tank to a fuel consumer by varying a speed of at least one main fuel tank pump associated with the main fuel tank relative to a speed of at least one wing fuel tank pump associated with the at least one wing fuel tank.

A system and method of controlling a fuel system on an aircraft includes selectively supplying fuel from either a main fuel tank or at least one wing fuel tank to a fuel consumer by varying a speed of at least one main fuel tank pump associated with the main fuel tank relative to a speed of at least one wing fuel tank pump associated with the at least one wing fuel tank.

A system comprises a non-transitory machine readable storage medium storing instructions and a database identifying a plurality of assets and a state of each asset. The instructions configure a processor for receiving updates to a distributed electronic ledger managed by plural peer processors. Each update includes an event or change affecting one of the assets. The peer processors verify portions of the ledger describing each event or change. At least one of the updates has not yet been recorded in the ledger at a time of the receiving. The processor computes a state of each asset, based on the updates, receives a request for a state of one of the assets; and responds to the request, reflecting each event and change affecting that asset. The response is performed without waiting for the peer processors to verify an update that has not yet been recorded in the ledger.

A system comprises a non-transitory machine readable storage medium storing instructions and a database identifying a plurality of assets and a state of each asset. The instructions configure a processor for receiving updates to a distributed electronic ledger managed by plural peer processors. Each update includes an event or change affecting one of the assets. The peer processors verify portions of the ledger describing each event or change. At least one of the updates has not yet been recorded in the ledger at a time of the receiving. The processor computes a state of each asset, based on the updates, receives a request for a state of one of the assets; and responds to the request, reflecting each event and change affecting that asset. The response is performed without waiting for the peer processors to verify an update that has not yet been recorded in the ledger.

A method of pumping fuel in a fuel system of a composite aircraft having a gas turbine engine includes feeding un-heated fuel from a fuel tank to the gas turbine engine, by using an ejector pump to draw the fuel from the fuel tank and feeding the fuel through an engine fuel pump within a main fuel line upstream of the gas turbine engine. Fuel from the main fuel line is bled and directed to the ejector pump via a motive flow pump assembly, the motive flow pump assembly including a motive flow pump generating a motive flow for the ejector pump. The bleed fuel flow is then passed through a hydrophobic fuel screen located upstream of the motive flow pump.

A method of pumping fuel in a fuel system of a composite aircraft having a gas turbine engine includes feeding un-heated fuel from a fuel tank to the gas turbine engine, by using an ejector pump to draw the fuel from the fuel tank and feeding the fuel through an engine fuel pump within a main fuel line upstream of the gas turbine engine. Fuel from the main fuel line is bled and directed to the ejector pump via a motive flow pump assembly, the motive flow pump assembly including a motive flow pump generating a motive flow for the ejector pump. The bleed fuel flow is then passed through a hydrophobic fuel screen located upstream of the motive flow pump.

An adapter system for a check valve which comprises a housing open at the bottom and a lateral wall pierced by a hole, and a flap fitted inside the housing and movable between a shut-off position in which the flap shuts off the hole and a free position in which the flap does not shut off the hole. A plug is provided for being inserted into the hole through an end face and a stop is provided for being placed against the lateral wall of the housing opposite the lateral wall pierced by the hole and comprising an attachment device provided for attaching the stop to the housing and provided so that the plug comes to rest against the stop. Such an adapter system may be installed without it being necessary to dismantle the housing.