Abstract: A turbine retention device is made by forming a bullet having a cylindrical geometry, forming a wing, coupling the wing to the bullet with a proximal portion of the wing along an axial length of the bullet, and coupling a mounting bracket to a distal end of the wing.

Abstract: A technique for mounting a turbine retention device is provided. The technique comprises forming openings in a diffuser, aligning a mounting bracket with the openings, and installing fasteners through the openings and the mounting bracket. A turbine retention device mounted to a diffuser may is also provided. The turbine retention device may comprise a bullet, wings coupled to the bullet, mounting brackets coupled to the wings, and fasteners disposed through the mounting brackets and openings formed in the diffuser.

Abstract: A turbine retention device is made by forming a bullet having a cylindrical geometry, forming a wing, coupling the wing to the bullet with a proximal portion of the wing along an axial length of the bullet, and coupling a mounting bracket to a distal end of the wing.

Abstract: A technique for mounting a turbine retention device is provided. The technique comprises forming openings in a diffuser, aligning a mounting bracket with the openings, and installing fasteners through the openings and the mounting bracket. A turbine retention device mounted to a diffuser may is also provided. The turbine retention device may comprise a bullet, wings coupled to the bullet, mounting brackets coupled to the wings, and fasteners disposed through the mounting brackets and openings formed in the diffuser.

Abstract: An APU has a control for controlling a load on the APU from an associated aircraft. The control further receives information with regard to a temperature challenge around the APU. If the temperature challenge exceeds a predetermined threshold, then the control operates the APU with a reduced load in a cool down cycle to reduce the heat load from the APU on an associated tail cone. A method is also disclosed.

Abstract: A combination fuel-oil and air-oil heat exchanger comprising: a first heat exchanger section that has an oil circulation path and a fuel circulation path thermally coupled to the oil circulation path; a second heat exchanger section that has an oil circulation path and an air circulation path thermally coupled to the oil circulation path; an oil coupling path that couples an oil circulation path outlet of the first heat exchanger section to an oil circulation path inlet of the second heat exchanger section to establish a combined oil circulation path; an oil path by-pass valve that selectively diverts oil from the combined oil circulation path to an outlet of the oil path by-pass valve; and a fuel path by-pass valve that selectively diverts fuel from the fuel circulation path of the first heat exchanger section to an outlet of the fuel path by-pass valve.

Abstract: An aircraft auxiliary power unit assembly includes an aircraft skin that provides a cavity. It is secured to a structure in an assembled condition and it provides an opening. An auxiliary power unit is arranged within the cavity and is secured to the structure. The aircraft skin substantially covers the auxiliary power unit in the assembled condition. An inlet duct that is removable is secured within the opening and is selectively connected to the auxiliary power unit between the installed and service positions. The installed and service positions are with the aircraft skin in the assembled condition.

Abstract: An aircraft auxiliary power unit assembly includes an aircraft skin that provides a cavity. It is secured to a structure in an assembled condition and it provides an opening. An auxiliary power unit is arranged within the cavity and is secured to the structure. The aircraft skin substantially covers the auxiliary power unit in the assembled condition. An inlet duct that is removable is secured within the opening and is selectively connected to the auxiliary power unit between the installed and service positions. The installed and service positions are with the aircraft skin in the assembled condition.

Abstract: A method of reducing engine noise for an engine under little or low load conditions includes the steps of: establishing an engine idle speed for the engine when the engine has less than a predetermined minimum level of load; measuring the level of load on the engine; measuring the speed of the engine; and reducing the speed of the engine to the engine idle speed if the measured level of load on the engine is less than the predetermined minimum level of load and the measured speed of the engine is greater than the engine idle speed.

Abstract: An aircraft auxiliary power unit assembly includes an aircraft skin providing a cavity. The aircraft skin is secured to a structure in an assembled condition and provides an opening. An auxiliary power unit is arranged within the cavity and secured to the structure. The aircraft skin substantially covers the auxiliary power unit in the assembled condition. An inlet duct is removably secured within the opening and is selectively connected to the auxiliary power unit between installed and service positions. The installed and service positions are with the aircraft skin in the assembled condition. A method of servicing the auxiliary power unit includes removing the auxiliary power unit inlet duct from the opening in the aircraft skin. The auxiliary power unit that is arranged within the cavity of the aircraft skin is exposed. A portion of the auxiliary power unit is serviced through the opening.

Abstract: An APU has a control for controlling a load on the APU from an associated aircraft. The control further receives information with regard to a temperature challenge around the APU. If the temperature challenge exceeds a predetermined threshold, then the control operates the APU with a reduced load in a cool down cycle to reduce the heat load from the APU on an associated tail cone. A method is also disclosed.

Abstract: An aircraft auxiliary power unit assembly includes an aircraft skin providing a cavity. The aircraft skin is secured to a structure in an assembled condition and provides an opening. An auxiliary power unit is arranged within the cavity and secured to the structure. The aircraft skin substantially covers the auxiliary power unit in the assembled condition. An inlet duct is removably secured within the opening and is selectively connected to the auxiliary power unit between installed and service positions. The installed and service positions are with the aircraft skin in the assembled condition. A method of servicing the auxiliary power unit includes removing the auxiliary power unit inlet duct from the opening in the aircraft skin. The auxiliary power unit that is arranged within the cavity of the aircraft skin is exposed. A portion of the auxiliary power unit is serviced through the opening.

Abstract: An inlet system, including for an auxiliary power unit includes an inlet louver mounted to an inlet duct, the inlet louver defines a multiple of vanes positioned to shield the inlet duct from fluids which fall in direction generally transverse to a free stream airflow.

Abstract: A combination fuel-oil and air-oil heat exchanger comprising: a first heat exchanger section that has an oil circulation path and a fuel circulation path thermally coupled to the oil circulation path; a second heat exchanger section that has an oil circulation path and an air circulation path thermally coupled to the oil circulation path; an oil coupling path that couples an oil circulation path outlet of the first heat exchanger section to an oil circulation path inlet of the second heat exchanger section to establish a combined oil circulation path; an oil path by-pass valve that selectively diverts oil from the combined oil circulation path to an outlet of the oil path by-pass valve; and a fuel path by-pass valve that selectively diverts fuel from the fuel circulation path of the first heat exchanger section to an outlet of the fuel path by-pass valve.

Abstract: An inlet system, including for an auxiliary power unit includes an inlet louver mounted to an inlet duct, the inlet louver defines a multiple of vanes positioned to shield the inlet duct from fluids which fall in direction generally transverse to a free stream airflow.

Abstract: The clearance between a seal assembly 46 and a turbine wheel 14 in a turbine engine of the type having a radial outflow compressor 24 and a radial inflow turbine wheel 14 may be minimized by utilizing a diaphragm assembly 76 as part of the seal assembly 46 and which is formed of multiple pieces in the form of concentric rings 78, 80. In addition, the thermal stress in the rings 78 and 80 will be considerably less than in a single ring as used in existing designs. This greatly extends the useful life of the seal plate assembly before the onset of cracking and other kinds of mechanical failure.

Abstract: The clearance between a seal assembly 48 and a turbine wheel 16 in an engine of the type having a radial outflow compressor 24 and a radial inflow turbine 16 is minimized by forming the seal assembly 48 in part out of a plurality of segments 74 disposed in a circular array and which are relatively movable but sealed to each other. The thermal stress in the segments 74 will be less than in a single ring resulting in an extended life before the onset of cracking and eventual mechanical failure.

Abstract: The selection of the mass of a mechanical damper 20 for a blade 12 in a turbine wheel 10, 12 independent of the size of a damper receiving opening 22 is achieved by making the damper 20, 40, 50, 60, partially hollow (FIG. 4) or completely hollow (FIGS. 5-7, inclusive).