An auxiliary power unit (APU) control system for an aircraft is disclosed. The APU control system includes an APU, one or more processors, and a memory coupled to the one or more processors. The memory stores data comprising a database and program code that, when executed by the one or more processors, causes the APU control system to receive a one or more ambient signals indicative of an air density value and one or more power signals indicative of a specific amount of power generated by the APU. The APU control system is further caused to determine a variable rotational speed of the APU based on the air density value and instruct the APU to operate at the variable rotational speed. The APU continues to generate the specific amount of power when operating at the variable rotational speed.

Systems and methods for condition-based validation of performance updates are provided. According to one embodiment of the disclosure, a method can include operating an asset under updated settings, ascertaining ambient conditions of the asset and matching the ambient conditions to a condition range, determining whether data completion criteria for the condition range are satisfied and, based at least in part on the determination, selectively switching between using the updated settings for operating the asset and using baseline settings for operating the asset while collecting data points for a predetermined period of time.

A method of controlling a gas turbine engine having a propulsive fan and an engine core, the method includes: measuring a first engine performance parameter indicative of the output of the fan; measuring a second engine performance parameter indicative of the output of the engine core; determining a thrust contribution generated by the fan based on a first power setting parameter and the first engine performance parameter; determining a thrust contribution generated by the engine core based on a second power setting parameter and the second engine performance parameter; determining the total thrust based on the fan thrust and core thrust; and controlling the engine based on the determined total thrust, wherein the total thrust includes the fan thrust and the engine core thrust.

A system includes a blower, a blower sensor, and at least one processor. The blower sensor is operably coupled to the blower and configured to obtain blower operational information. The at least one processor is operably coupled to the blower and the blower sensor, and is configured to determine an operational-based power using the blower operational information; determine an operational-based density using the operational-based power; and control the blower using the operational-based density.

A system for adjusting a variable position vane in an aircraft engine is disclosed. The system comprises a servo valve operatively connected to the variable position vane and configured to cause adjustment of the variable position vane based on a pressure of air pressurized by a compressor of the aircraft engine.

This invention concerns an aircraft propulsion system in which an engine has an engine core comprising a compressor, a combustor and a turbine driven by a flow of combustion products of the combustor. At least one propulsive fan generates a mass flow of air to propel the aircraft. An electrical energy store is provided on board the aircraft. At least one electric motor is arranged to drive the propulsive fan and the engine core compressor. A controller controls the at least one electric motor to mitigate the creation of a contrail caused by the engine combustion products by altering the ratio of the mass flow of air by the propulsive fan to the flow of combustion products of the combustor. The at least one electric motor is controlled so as to selectively drive both the propulsive fan and engine core compressor.

In a compressed air energy storage and power generation device, a compressed air energy storage and power generation method defines, as a reference storage value, a storage value indicating that a storage amount of air in an accumulator tank is in a predetermined intermediate state. At the reference storage value, at least one of a motor and a generator rotates at a rated rotation speed. When a storage value indicating a current storage amount in the accumulator tank is larger than the reference storage value, at least one of the motor and the generator is controlled to rotate at equal to or less than the rated rotation speed. When the storage value indicating the current storage amount in the accumulator tank is smaller than the reference storage value, at least one of the motor and the generator is controlled to rotate at equal to or more than the rated rotation speed and equal to or less than a maximum permissible rotation speed.

A variable-geometry system for a gas turbine engine can be used to improve operations in various inclement weather conditions. This may be achieved by varying the orientation of an element in a gas turbine engine flowpath in response to a comparison between sensor-gathered parameter data and stored parameter values and ranges using a pre-programmed algorithm. The orientation of the element may be infinitely variable within a range of orientations.

In a compressed air energy storage and power generation device, a compressed air energy storage and power generation method defines, as a reference storage value, a storage value indicating that a storage amount of air in an accumulator tank is in a predetermined intermediate state. At the reference storage value, at least one of a motor and a generator rotates at a rated rotation speed. When a storage value indicating a current storage amount in the accumulator tank is larger than the reference storage value, at least one of the motor and the generator is controlled to rotate at equal to or less than the rated rotation speed. When the storage value indicating the current storage amount in the accumulator tank is smaller than the reference storage value, at least one of the motor and the generator is controlled to rotate at equal to or more than the rated rotation speed and equal to or less than a maximum permissible rotation speed.

A bleed valve for an air plenum includes a valve body having a poppet seat, a poppet supported by the valve body and movable relative to the poppet seat, and piston slideable relative to the poppet and movable relative to the poppet between an extended position and a retracted position. Gas turbine engines and methods of bleeding fluid from gas turbine engines are also described.