Abstract: A gas turbine engine defining a radial direction is provided. The gas turbine engine includes a tie shaft; a compressor section including a last rotor stage, the compressor section assembled to a first portion of the tie shaft; a separable shaft disposed between the compressor section and the tie shaft, the separable shaft having a radial outward portion and a radial inward portion, the radial outward portion of the separable shaft in contact with a portion of the last rotor stage at an interface; and a seal assembly operable with a portion of the separable shaft proximate the radial inward portion.

Abstract: A gas turbine engine defining a radial direction is provided. The gas turbine engine includes a tie shaft; a compressor section including a last rotor stage, the compressor section assembled to a first portion of the tie shaft; a separable shaft disposed between the compressor section and the tie shaft, the separable shaft having a radial outward portion and a radial inward portion, the radial outward portion of the separable shaft in contact with a portion of the last rotor stage at an interface; and a seal assembly operable with a portion of the separable shaft proximate the radial inward portion.

Abstract: A method of assembling a gas turbine engine that includes providing a rotor assembly including a rotor shaft, an air duct, and a rotor disk that includes a mounting arm, wherein the mounting arm extends radially inward from the rotor disk towards the rotor shaft and coupling a rotor impeller assembly to the mounting arm, wherein the rotor impeller assembly includes a carrier and a plurality of bleed tubes that each extend outwardly from the carrier and are configured to receive bleed air.

Abstract: A method for chemical milling of a gas turbine engine blisk having a hub and a plurality of blades made of metal for the purpose of changing the dimensional characteristics (i.e., chord and/or thickness) of one or more of these blades. At least one blade of the blisk is treated with a chemical etchant of the metal that the blade is made of for a period of time sufficient to change at least one of the chord and thickness of the blade(s). In a preferred aspect of this method, at least one of the blades of a rotationally imbalanced blisk is treated with the chemical etchant for a period of time sufficient to change the chord and/or thickness of these blades so that the blisk is rotationally balanced. In another preferred aspect of this method, an assessment of where and the degree to which the rotational imbalance exists in the blisk is made to determine which blades are to be treated with the chemical etchant and how those blades are to be treated to achieve rotational balance of the blisk.

Abstract: A method for chemical milling of a gas turbine engine blisk having a hub and a plurality of blades made of metal for the purpose of changing the dimensional characteristics (i.e., chord and/or thickness) of one or more of these blades. At least one blade of the blisk is treated with a chemical etchant of the metal that the blade is made of for a period of time sufficient to change at least one of the chord and thickness of the blade(s). In a preferred aspect of this method, at least one of the blades of a rotationally imbalanced blisk is treated with the chemical etchant for a period of time sufficient to change the chord and/or thickness of these blades so that the blisk is rotationally balanced.

Abstract: A blisk includes a disk having a rim from which extends a row of blades. The rim includes axially opposite overhangs one of which includes an arcuate balance land disposed eccentrically to the centerline axis of the disk for balancing the blisk.