A metal catalytic converter system employs an engine having an exhaust duct. A multistage metal catalytic converter is mounted in the exhaust duct. A compressor stage is mounted in the exhaust duct, the compressor stage configured to reduce exhaust backpressure created by the converter.

An airfoil for a fan section of a turbine engine may include a fan blade or an outlet guide vane, and an edge guard attached thereto. The edge guard may include a heating conduit disposed within at least a portion of the edge guard. An anti-icing system for a plurality of fan blades or outlet guide vanes may include a fluid supply pathway configured to supply heating fluid to respective ones of a plurality of heating conduits within the edge guards attached to respective ones of a plurality of fan blades and/or to a plurality of outlet guide vanes. The heating fluid may include bleed air from a core air flowpath. A method of inhibiting icing on an airfoil may include flowing a heating fluid into a heating conduit disposed within an edge guard attached to the airfoil and heating the edge guard with the heating fluid.

An airfoil for a fan section of a turbine engine may include a fan blade or an outlet guide vane, and an edge guard attached thereto. The edge guard may include a heating conduit disposed within at least a portion of the edge guard. An anti-icing system for a plurality of fan blades or outlet guide vanes may include a fluid supply pathway configured to supply heating fluid to respective ones of a plurality of heating conduits within the edge guards attached to respective ones of a plurality of fan blades and/or to a plurality of outlet guide vanes. The heating fluid may include bleed air from a core air flowpath. A method of inhibiting icing on an airfoil may include flowing a heating fluid into a heating conduit disposed within an edge guard attached to the airfoil and heating the edge guard with the heating fluid.

A combustion chamber includes a bottom wall having at least one opening, at least one sleeve mounted upstream of the bottom wall and fixed to the bottom wall, a closing ring defining an annular groove with the sleeve and fixed to the sleeve, and at least one air and fuel injection system having an axis, mounted in the opening of the bottom wall. The injection system has an annular flange extending radially with respect to the axis and is mounted in the groove with radial clearance. A baffle is situated downstream of the bottom wall and is fixed to the sleeve and/or to the bottom wall.

A combustion chamber includes a bottom wall having at least one opening, at least one sleeve mounted upstream of the bottom wall and fixed to the bottom wall, a closing ring defining an annular groove with the sleeve and fixed to the sleeve, and at least one air and fuel injection system having an axis, mounted in the opening of the bottom wall. The injection system has an annular flange extending radially with respect to the axis and is mounted in the groove with radial clearance. A baffle is situated downstream of the bottom wall and is fixed to the sleeve and/or to the bottom wall.

A gas turbine engine according to an example of the present disclosure may include, among other things, a fan section including a fan having a plurality of fan blades and including an outer housing surrounding the fan blades to establish a bypass duct, a geared architecture, a first spool including a first shaft that interconnects a first compressor and a fan drive turbine, the fan drive turbine driving the fan through the geared architecture. The gas turbine engine is rated to provide an amount of thrust at ground idle, and the gas turbine engine is rated to provide an amount of thrust at maximum takeoff. A thrust ratio is defined as a ratio of the amount of thrust at ground idle divided by the amount of thrust at maximum takeoff. The thrust ratio can be less than or equal to 0.050.

A gas turbine engine according to an example of the present disclosure may include, among other things, a fan section including a fan having a plurality of fan blades and including an outer housing surrounding the fan blades to establish a bypass duct, a geared architecture, a first spool including a first shaft that interconnects a first compressor and a fan drive turbine, the fan drive turbine driving the fan through the geared architecture. The gas turbine engine is rated to provide an amount of thrust at ground idle, and the gas turbine engine is rated to provide an amount of thrust at maximum takeoff. A thrust ratio is defined as a ratio of the amount of thrust at ground idle divided by the amount of thrust at maximum takeoff. The thrust ratio can be less than or equal to 0.050.

Electrical power system includes: one or more rotary electric machines, each mechanically coupled to a gas turbine engine spool; a set of converter circuits connected to the one or more rotary electric machines for conversion between alternating (ac) and direct current (dc), wherein one or more rotary electric machines and the set of converter circuits are arranged to output a number R≥2 of dc power channels, each dc power channel having a respective index r=(1, . . . , R); and a group of N dc load channels connected to the R dc power channels by a switching arrangement, wherein N>R and each dc load channel has a respective index n=(1, . . . , N). The switching arrangement is operable to connect a number Q≥1 of the N load channels to at least two different power channels of the R power channels.

Electrical power systems for distributing electrical power in arrangements including one or more gas turbine engines; one such system includes: one or more rotary electric machines coupled to a gas turbine engine spool; a set of converter circuits connected to the rotary electric machines converting between alternating current (ac) and direct current (dc), wherein the rotary electric machines and the converter circuits output a number R≥2 of dc power channels, each channel having an index r=(1, . . . , R); and a group of N dc load channels connected to the R dc power channels by a switching arrangement, wherein N>R and each dc load channel has an index n=(1, . . . , N). For each respective N load channels, a current limiting device (CLD) limits the current flowing from power channels to a load connectable to the electrical power system via the respective load channel.

Electrical power systems for distributing electrical power in arrangements including one or more gas turbine engines; one such system includes: one or more rotary electric machines coupled to a gas turbine engine spool; a set of converter circuits connected to the rotary electric machines converting between alternating current (ac) and direct current (dc), wherein the rotary electric machines and the converter circuits output a number R≥2 of dc power channels, each channel having an index r=(1, . . . , R); and a group of N dc load channels connected to the R dc power channels by a switching arrangement, wherein N>R and each dc load channel has an index n=(1, . . . , N). For each respective N load channels, a current limiting device (CLD) limits the current flowing from power channels to a load connectable to the electrical power system via the respective load channel.