A multi-engine aircraft includes a first engine drivingly engaged to a common rotatable load and a second engine drivingly engaged to the common rotatable load, the second engine having a bleed air system and a control system in communication with a compressed air switching system. The control system controls operation of the second engine and/or the compressed air switching system. The compressed air switching system includes a switching valve that is displaceable between at least a first position and a second position, the first position interconnecting a lower pressure inlet and a switch outlet, and the second position interconnecting a high pressure inlet and the switch outlet. The switch outlet is in communication with the bleed air system of the second engine. The control system actuates the switching valve to switch between the first and second positions.

A method of determining a state of a switching valve of a bleed air system in a gas turbine engine of an aircraft includes determining a temperature in a main gas path of the gas turbine engine at a location at or downstream of the combustor and then actuating the switching valve of the bleed air system to bleed air from a different bleed location. The temperature is determined after actuating the switching valve. In response to determining that a difference between the temperatures before and after the actuation of the switching valve meets a threshold, executing at least one of a first action and a second action with respect to the gas turbine engine and/or the switching valve.

An aircraft gas turbine engine system comprises first and second gas turbine engines. The first gas turbine engine has first and second spools. A first power linkage connects the second gas turbine engine to the first spool of the gas turbine engine, and a second power linkage connects the second gas turbine engine to the second spool of the first gas turbine engine.

This invention relates to shaft-less twin rotor turbomachinery and the applications the shaft-less turbomachine has a twin tubing rotator assembly with vortical effect passages forming a high power zone and lower power zone, the twin tubing rotator assembly has two rotors to rotate independently or together with multiple powers universal bearings, high speed seal assemblies, it combines the best features of high flow rate of axial turbomachine and high pressure output of centrifugal turbomachine with the most efficient blade and turbine designs, it represents a new era of this turbomachine, disrupt invention and would power millions of turbomachines like the turbo pumps for rocket engines, jet engine/ramjet, submarines/torpedo and ships with the most advanced propellers as well as compression/pumping stations, turbines for power plants at an unprecedented level of efficiency and reliability with the twin tubing full port rotor assembly.

This invention relates to shaft-less twin rotor turbomachinery and the applications the shaft-less turbomachine has a twin tubing rotator assembly with vortical effect passages forming a high power zone and lower power zone, the twin tubing rotator assembly has two rotors to rotate independently or together with multiple powers universal bearings, high speed seal assemblies, it combines the best features of high flow rate of axial turbomachine and high pressure output of centrifugal turbomachine with the most efficient blade and turbine designs, it represents a new era of this turbomachine, disrupt invention and would power millions of turbomachines like the turbo pumps for rocket engines, jet engine/ramjet, submarines/torpedo and ships with the most advanced propellers as well as compression/pumping stations, turbines for power plants at an unprecedented level of efficiency and reliability with the twin tubing full port rotor assembly.

A hybrid electric system for a rotorcraft can include a first thermal engine, a second thermal engine, and an electrical machine. The first thermal engine can be sized to produce a maximum first thermal engine power that is below a one-or-more-engine-inoperative (OEI) requirement power and the second thermal engine can be sized to produce a maximum second thermal engine power that is below the OEI requirement power. The electrical machine can be sized to provide at least a remaining power needed to reach the OEI requirement power in an OEI state.

A gas turbine engine utilizes one or more gas generators having a core inlet flowpath and an exhaust outlet. Adjacently offset from the core gas generator, is a propulsor assembly. An exhaust outlet of the core gas generator is fluidly connected to the propulsor assembly and exhaust from the gas generator drives a fan drive turbine.

A gas turbine engine utilizes one or more gas generators having a core inlet flowpath and an exhaust outlet. Adjacently offset from the core gas generator, is a propulsor assembly. An exhaust outlet of the core gas generator is fluidly connected to the propulsor assembly and exhaust from the gas generator drives a fan drive turbine.

Two turboshaft engines are interwoven so as to exchange thermal energy by heat exchangers which improve their efficiency, without greatly increasing head losses since the pipes imposed to serve the exchangers are short and include a single bend.

Two turboshaft engines are interwoven so as to exchange thermal energy by heat exchangers which improve their efficiency, without greatly increasing head losses since the pipes imposed to serve the exchangers are short and include a single bend.