The subject matter of this specification can be embodied in, among other things, a system includes a turbofan engine, a nacelle surrounding the engine and defining an annular bypass duct through the engine to define a generally forward-to-aft bypass air flow path, a thrust reverser movable to and from a reversing position where at least a portion of the bypass air flow path is reversed and comprising a first reverser portion having a first latch element, and a second reverser portion having a second latch element that is reversibly engageable with the first latch element to reversibly secure the second reverser portion to the first reverser portion, and an actuator comprising a catch element coupled to a portion of at least one of the first latch element and the second latch element to move the first reverser portion and the second reverser portion into and out of the reversing position.

The subject matter of this specification can be embodied in, among other things, a system includes a turbofan engine, a nacelle surrounding the engine and defining an annular bypass duct through the engine to define a generally forward-to-aft bypass air flow path, a thrust reverser movable to and from a reversing position where at least a portion of the bypass air flow path is reversed and comprising a first reverser portion having a first latch element, and a second reverser portion having a second latch element that is reversibly engageable with the first latch element to reversibly secure the second reverser portion to the first reverser portion, and an actuator comprising a catch element coupled to a portion of at least one of the first latch element and the second latch element to move the first reverser portion and the second reverser portion into and out of the reversing position.

A method of calibrating a gas turbine engine having a propulsive fan, and an engine core, the method including: measuring a total thrust generated by the engine; measuring the thrust generated by the engine core; measuring first and second engine performance parameters; based on the total thrust and engine core thrust, determining a thrust generated by the propulsive fan; providing a first power setting parameter associating the fan thrust with the first engine performance parameter; and providing a second power setting parameter associating the engine core thrust with the second engine performance parameter.

A method of calibrating a gas turbine engine having a propulsive fan, and an engine core, the method including: measuring a total thrust generated by the engine; measuring the thrust generated by the engine core; measuring first and second engine performance parameters; based on the total thrust and engine core thrust, determining a thrust generated by the propulsive fan; providing a first power setting parameter associating the fan thrust with the first engine performance parameter; and providing a second power setting parameter associating the engine core thrust with the second engine performance parameter.

A gas turbine engine is disclosed which includes a bypass passage that in some embodiments are capable of being configured to act as a resonance space. The resonance space can be used to attenuate/accentuate/etc a noise produced elsewhere. The bypass passage can be configured in a number of ways to form the resonance space. For example, the space can have any variety of geometries, configurations, etc. In one non-limiting form the resonance space can attenuate a noise forward of the bypass duct. In another non-limiting form the resonance space can attenuate a noise aft of the bypass duct. Any number of variations is possible.

A gas turbine engine comprising: a compressor; a first turbine; and a first compressor bleed valve in fluid communication with the compressor and configured to release bleed air from the compressor; wherein the first compressor bleed valve is configured to release bleed air to a downstream location in the engine, the downstream location being downstream of the first turbine; wherein the first compressor bleed valve is configured to open wherein the first compressor bleed valve is configured to open to at least two positions, to thereby release a variable amount of bleed air from the compressor.

A gas turbine engine comprising: a compressor; a first turbine; and a first compressor bleed valve in fluid communication with the compressor and configured to release bleed air from the compressor; wherein the first compressor bleed valve is configured to release bleed air to a downstream location in the engine, the downstream location being downstream of the first turbine; wherein the first compressor bleed valve is configured to open wherein the first compressor bleed valve is configured to open to at least two positions, to thereby release a variable amount of bleed air from the compressor.

A turbofan engine with a nacelle and a flow path, in which the nacelle comprises a movable cowl that makes it possible to define a window between the flow path and the outside, veils with a first edge fixed to the movable cowl and alternately assuming a folded position or a deployed position across the flow path, and a pneumatic system displacing a second edge of the veils from the folded position to the deployed position and vice versa. The pneumatic system comprises a rigid main roll, for each veil, at least one extendable secondary roll fixed to a second edge of the veil, and a pressurization and depressurization system which, alternately, generates a pressure or a depression in each secondary roll. Replacing the reverse doors and their driving mechanisms with flexible veils and a pneumatic system allows for a weight reduction.

An inlet arrangement is disclosed herein for use with a supersonic jet engine configured to consume air at a predetermined mass flow rate when the supersonic jet engine is operating at a predetermined power setting and moving at a predetermined Mach speed. The air inlet arrangement includes, but is not limited to, a cowl having a cowl lip and a center body coaxially aligned with the cowl. A protruding portion of the center body extends upstream of the cowl lip for a length greater than a conventional spike length. The protruding portion is configured to divert air flowing over the protruding portion out of a pathway of an inlet to the supersonic jet engine such that a remaining airflow approaching and entering the inlet matches the predetermined mass flow rate.

An inlet arrangement is disclosed herein for use with a supersonic jet engine configured to consume air at a predetermined mass flow rate when the supersonic jet engine is operating at a predetermined power setting and moving at a predetermined Mach speed. The air inlet arrangement includes, but is not limited to, a cowl having a cowl lip and a center body coaxially aligned with the cowl. A protruding portion of the center body extends upstream of the cowl lip for a length greater than a conventional spike length. The protruding portion is configured to divert air flowing over the protruding portion out of a pathway of an inlet to the supersonic jet engine such that a remaining airflow approaching and entering the inlet matches the predetermined mass flow rate.