Abstract: A gas turbine engine assembly may include, among other things, a fan section including a fan, the fan including a plurality of fan blades, a diameter of the fan having a dimension D, each fan blade having a leading edge, and a forward most portion on the leading edges of the fan blades in a first reference plane, a geared architecture, a turbine section including a high pressure turbine and a low pressure turbine, the low pressure turbine driving the fan through the geared architecture, a nacelle surrounding the fan, the nacelle including an inlet portion forward of the fan, a forward edge on the inlet portion in a second reference plane, and a length of the inlet portion having a dimension L between the first reference plane and the second reference plane. A dimensional relationship of L/D may be between 0.30 and 0.40.

Abstract: A gas turbine engine assembly includes, among other things, a fan section including a fan, the fan including a plurality of fan blades, a diameter of the fan having a dimension D that is based on a dimension of the fan blades, a turbine section including a high pressure turbine and a low pressure turbine, the low pressure turbine driving the fan, a nacelle including an inlet portion forward of the fan, a length of the inlet portion having a dimension L, and a dimensional relationship of L/D between 0.30 and 0.40.

Abstract: A gas turbine engine includes a fan section including a fan. A fan nacelle surrounds the fan and includes an inlet with an inlet leading edge plane and a throat. A compressor section is arranged in a core nacelle and includes a first compressor and a second compressor. A turbine section is arranged in the core nacelle and includes a fan drive turbine and a second turbine. A fan hub mounts the fan and a spinner axially forward of the fan. The fan drive turbine drives the fan through a geared architecture. The fan includes a fan leading edge forward-most point spaced apart from the inlet leading edge plane by an inlet length. The spinner includes a spinner length from a spinner forward-most point to the fan leading edge forward-most point. A ratio of the spinner length to inlet length is greater than or equal to 0.5.

Abstract: A gas turbine engine that includes a fan nacelle and a core nacelle that provide a bypass flow path radially between. The fan nacelle has an inlet including a throat. The inlet has an inlet forward-most point. A fan is arranged in the bypass flow path and rotatable about an axis. The fan has a leading edge recessed from the inlet forward-most point an inlet length in an axial direction. A spinner has a spinner length from a spinner forward-most point to the leading edge. A ratio of the spinner length to inlet length is equal to or greater than about 0.5.

Abstract: According to an example embodiment, a gas turbine engine assembly includes, among other things, a fan section including a fan, the fan including a plurality of fan blades, a diameter of the fan having a dimension D that is based on a dimension of the fan blades, each fan blade having a leading edge, and a forward most portion on the leading edges of the fan blades in a first reference plane, a geared architecture, a turbine section including a high pressure turbine and a low pressure turbine, the low pressure turbine driving the fan through the geared architecture, a nacelle surrounding the fan, the nacelle including an inlet portion forward of the fan, a forward edge on the inlet portion in a second reference plane, and a length of the inlet portion having a dimension L measured along an engine axis between the first reference plane and the second reference plane. A dimensional relationship of L/D is between 0.20 and 0.40.

Abstract: A gas turbine engine assembly may include, among other things, a fan section including a fan, the fan including a plurality of fan blades, a diameter of the fan having a dimension D, each fan blade having a leading edge, and a forward most portion on the leading edges of the fan blades in a first reference plane, a geared architecture, a turbine section including a high pressure turbine and a low pressure turbine, the low pressure turbine driving the fan through the geared architecture, a nacelle surrounding the fan, the nacelle including an inlet portion forward of the fan, a forward edge on the inlet portion in a second reference plane, and a length of the inlet portion having a dimension L between the first reference plane and the second reference plane. A dimensional relationship of L/D may be between 0.30 and 0.40.

Abstract: A gas turbine engine assembly includes, among other things, a fan section including a fan, the fan including a plurality of fan blades, a diameter of the fan having a dimension D that is based on a dimension of the fan blades, a turbine section including a high pressure turbine and a low pressure turbine, the low pressure turbine driving the fan, a nacelle including an inlet portion forward of the fan, a length of the inlet portion having a dimension L, and a dimensional relationship of L/D between 0.30 and 0.40.

Abstract: According to an example embodiment, a gas turbine engine assembly includes, among other things, a fan section including a fan, the fan including a plurality of fan blades, a diameter of the fan having a dimension D that is based on a dimension of the fan blades, each fan blade having a leading edge, and a forward most portion on the leading edges of the fan blades in a first reference plane, a turbine section including a high pressure turbine and a low pressure turbine, the low pressure turbine driving the fan, a nacelle including an inlet portion forward of the fan, a forward edge on the inlet portion in a second reference plane, and a length of the inlet portion having a dimension L measured along an engine axis between the first reference plane and the second reference plane. A dimensional relationship of L/D is no more than 0.45.

Abstract: A fan assembly for a gas turbine engine includes a fan including a plurality of fan blades. Each fan blade extends radially outwardly from a fan hub to a blade tip. The plurality of blade tips define a fan diameter. A nacelle surrounds the fan and defines a fan inlet upstream of the fan, relative to an airflow direction into the fan. The nacelle has a forwardmost edge defining an inlet length from the forwardmost edge to a leading edge of a fan blade of the plurality of fan blades. A ratio of inlet length to fan diameter is between 0.20 and 0.45. A nacelle inner surface defines a nacelle flowpath. The nacelle flowpath has a convex throat portion and a concave diffusion portion between the throat portion and the leading edge of the fan blade at a bottommost portion of the nacelle.

Abstract: A gas turbine engine assembly includes a fan. A diameter of the fan has a dimension D. The fan has a pressure ratio of greater than 1.20 and less than 1.45. A leading edge on an inlet portion of a nacelle is within a first reference plane oriented at an oblique angle. A forward most portion on the fan blade leading edges is in a second reference plane. A length of the inlet portion has a dimension L different at a plurality of locations on the inlet portion. A geared architecture has a gear reduction ratio of greater than 2.3, a bypass ratio is greater than 10, and a low pressure turbine includes a pressure ratio greater than 5:1. A dimensional relationship of UD is between 0.25 and 0.45. The leading edge on the inlet portion is further from the second reference plane near the top of the assembly.

Abstract: According to an example embodiment, a gas turbine engine assembly includes, among other things, a fan section including a fan, the fan including a plurality of fan blades, a diameter of the fan having a dimension D that is based on a dimension of the fan blades, each fan blade having a leading edge, and a forward most portion on the leading edges of the fan blades in a first reference plane, a geared architecture, a turbine section including a high pressure turbine and a low pressure turbine, the low pressure turbine driving the fan through the geared architecture, a nacelle surrounding the fan, the nacelle including an inlet portion forward of the fan, a forward edge on the inlet portion in a second reference plane, and a length of the inlet portion having a dimension L measured along an engine axis between the first reference plane and the second reference plane. A dimensional relationship of L/D is between 0.20 and 0.40.

Abstract: A fan assembly for a gas turbine engine includes a fan including a plurality of fan blades extending radially outwardly from a fan hub to a blade tip defining a fan diameter. A nacelle surrounds the fan and defines a fan inlet upstream of the fan, relative to an airflow direction into the fan. The nacelle has a forwardmost edge defining an inlet length from the forwardmost edge to a leading edge of a fan blade. A ratio of inlet length to fan diameter is between 0.20 and 0.45. A nacelle inner surface defines a nacelle flowpath having a convex throat portion and a diffusion portion between the throat portion and the leading edge of the fan blade at a topmost portion of the nacelle. The throat portion has a minimum throat radius measured from a fan central axis greater than a blade tip radius.

Abstract: According to an example embodiment, a gas turbine engine assembly includes, among other things, a fan section including a fan, the fan including a plurality of fan blades, a diameter of the fan having a dimension D that is based on a dimension of the fan blades, each fan blade having a leading edge, and a forward most portion on the leading edges of the fan blades in a first reference plane, a geared architecture, a turbine section including a high pressure turbine and a low pressure turbine, the low pressure turbine driving the fan through the geared architecture, a nacelle surrounding the fan, the nacelle including an inlet portion forward of the fan, a forward edge on the inlet portion in a second reference plane, and a length of the inlet portion having a dimension L measured along an engine axis between the first reference plane and the second reference plane. A dimensional relationship of L/D is no more than 0.45.

Abstract: According to an example embodiment, a gas turbine engine assembly includes, among other things, a fan section including a fan, the fan including a plurality of fan blades, a diameter of the fan having a dimension D that is based on a dimension of the fan blades, each fan blade having a leading edge, and a forward most portion on the leading edges of the fan blades in a first reference plane, a turbine section including a high pressure turbine and a low pressure turbine, the low pressure turbine driving the fan, a nacelle including an inlet portion forward of the fan, a forward edge on the inlet portion in a second reference plane, and a length of the inlet portion having a dimension L measured along an engine axis between the first reference plane and the second reference plane. A dimensional relationship of L/D is no more than 0.45.

Abstract: According to an example embodiment, a gas turbine engine assembly includes, among other things, a fan section including a fan, the fan including a plurality of fan blades, a diameter of the fan having a dimension D that is based on a dimension of the fan blades, each fan blade having a leading edge, and a forward most portion on the leading edges of the fan blades in a first reference plane, a geared architecture, a turbine section including a high pressure turbine and a low pressure turbine, the low pressure turbine driving the fan through the geared architecture, a nacelle surrounding the fan, the nacelle including an inlet portion forward of the fan, a forward edge on the inlet portion in a second reference plane, and a length of the inlet portion having a dimension L measured along an engine axis between the first reference plane and the second reference plane. A dimensional relationship of L/D is no more than 0.45.

Abstract: According to an example embodiment, a gas turbine engine assembly includes, among other things, a fan that has a plurality of fan blades. A diameter of the fan has a dimension D that is based on a dimension of the fan blades. Each fan blade has a leading edge. An inlet portion is situated forward of the fan. A length of the inlet portion has a dimension L between a location of the leading edge of at least some of the fan blades and a forward edge on the inlet portion. A dimensional relationship of L/D is between about 0.2 and about 0.45.

Abstract: According to an example embodiment, a gas turbine engine assembly includes, among other things, a fan that has a plurality of fan blades. A diameter of the fan has a dimension D that is based on a dimension of the fan blades. Each fan blade has a leading edge. An inlet portion is situated forward of the fan. A length of the inlet portion has a dimension L between a location of the leading edge of at least some of the fan blades and a forward edge on the inlet portion. A dimensional relationship of L/D is between about 0.2 and 0.45.

Abstract: A fan assembly for a gas turbine engine includes a fan including a plurality of fan blades. Each fan blade extends radially outwardly from a fan hub to a blade tip. The plurality of blade tips define a fan diameter. A nacelle surrounds the fan and defines a fan inlet upstream of the fan, relative to an airflow direction into the fan. The nacelle has a forwardmost edge defining an inlet length from the forwardmost edge to a leading edge of a fan blade of the plurality of fan blades. A ratio of inlet length to fan diameter is between 0.20 and 0.45. A nacelle inner surface defines a nacelle flowpath. The nacelle flowpath has a convex throat portion and a concave diffusion portion between the throat portion and the leading edge of the fan blade at a bottommost portion of the nacelle.

Abstract: A fan assembly for a gas turbine engine includes a fan including a plurality of fan blades extending radially outwardly from a fan hub to a blade tip defining a fan diameter. A nacelle surrounds the fan and defines a fan inlet upstream of the fan, relative to an airflow direction into the fan. The nacelle has a forwardmost edge defining an inlet length from the forwardmost edge to a leading edge of a fan blade. A ratio of inlet length to fan diameter is between 0.20 and 0.45. A nacelle inner surface defines a nacelle flowpath having a convex throat portion and a diffusion portion between the throat portion and the leading edge of the fan blade at a topmost portion of the nacelle. The throat portion has a minimum throat radius measured from a fan central axis greater than a blade tip radius.

Abstract: A gas turbine engine comprises a nacelle and a fan rotor carrying a plurality of fan blades. The nacelle is formed with droop such that one portion extends axially further from the fan blades than does another portion. The nacelle has inner periphery that is substantially axially symmetric about a center axis of the rotor from either a throat of the nacelle at a substantially bottom dead center location, or a point of inflection at which the inner periphery of the nacelle at substantially bottom dead center merges a convex portion into a concave portion.