A gas turbine engine (10) comprising: a high pressure turbine (17); a low pressure turbine (19); a high pressure compressor (15) coupled to the high pressure turbine (17) by a high pressure shaft (27); a propulsor (23) and a low pressure compressor (14) coupled to the low pressure turbine (19) via a low pressure shaft (26) and a reduction gearbox (30); wherein the low pressure compressor (14) consists of four compressor stages (14) and defines a cruise pressure ratio of between 2.4:1 and 3.3:1; the high pressure compressor (15) defines a cruise pressure ratio of less than 17:1; and the high pressure compressor (15) and low pressure compressor (14) together define a cruise core overall pressure ratio of greater than 36:1.

A gas turbine engine includes a very high speed low pressure turbine such that a quantity defined by the exit area of the low pressure turbine multiplied by the square of the low pressure turbine rotational speed compared to the same parameters for the high pressure turbine is at a ratio between about 0.5 and about 1.5. The high pressure turbine is supported by a bearing positioned at a point where the first shaft connects to a hub carrying turbine rotors associated with the second turbine section.

A gas turbine engine includes a very high speed low pressure turbine such that a quantity defined by the exit area of the low pressure turbine multiplied by the square of the low pressure turbine rotational speed compared to the same parameters for the high pressure turbine is at a ratio between about 0.5 and about 1.5. The high pressure turbine is supported by a bearing positioned at a point where the first shaft connects to a hub carrying turbine rotors associated with the second turbine section.

A gas turbine engine has a compression system radius ratio defined as the ratio of the radius of the tip of a fan blade to the radius of the tip of the most downstream compressor blade in the range of from 5 to 9. This results in an optimum balance between installation benefits, operability, maintenance requirements and engine efficiency when the gas turbine engine is installed on an aircraft.

A gas turbine engine has a compression system radius ratio defined as the ratio of the radius of the tip of a fan blade to the radius of the tip of the most downstream compressor blade in the range of from 5 to 9. This results in an optimum balance between installation benefits, operability, maintenance requirements and engine efficiency when the gas turbine engine is installed on an aircraft.

A turbine engine that includes an engine core, an inner cowl, an outer cowl and an accessory gearbox. The engine core includes at least a compressor section, a combustion section, and a turbine section in axial flow arrangement. The accessory gearbox is operably coupled to the engine core and includes a first portion and a second portion.

A turbine engine that includes an engine core, an inner cowl, an outer cowl and an accessory gearbox. The engine core includes at least a compressor section, a combustion section, and a turbine section in axial flow arrangement. The accessory gearbox is operably coupled to the engine core and includes a first portion and a second portion.

A method of assembling a gas turbine engine is disclosed herein. The method comprises providing a set of standard axial compressor stages. Each axial compressor stage included in the set of standard axial compressor stages includes a rotor having a plurality of blades configured to rotate about an axis and a stator having a plurality of stator vanes.

A method of assembling a gas turbine engine is disclosed herein. The method comprises providing a set of standard axial compressor stages. Each axial compressor stage included in the set of standard axial compressor stages includes a rotor having a plurality of blades configured to rotate about an axis and a stator having a plurality of stator vanes.

A sealing apparatus for an axial flow turbomachine is disclosed. An example axial flow turbomachine includes band segments bordering a flow path, a first spline seal disposed at a first angle within a first slot of the band segments, a second spline seal disposed at second angle within a second slot of the band segments, a Z-seal disposed across a gap between the first slot and the second, the Z-seal positioned at least partially within the first slot and the second slot. The Z-seal includes a first segment disposed at the first angle at least partially within the first slot, the first segment to contact the first spline seal, a second segment disposed at the second angle at least partially within the second slot, a portion of the second segment in connection with a portion of the first segment, the second segment to contact the second spline seal.