Abstract: An aircraft comprises a hydrogen-fuelled propulsion system, a plurality of like generally cylindrical hydrogen storage tanks and a conveying system arranged to convey hydrogen from the hydrogen storage tanks to the hydrogen-fuelled propulsion system. The aircraft further comprises a fuselage having a cargo bay (502) including one or more (510A-G) of the plurality of hydrogen storage tanks, the longitudinal axes (511A-G) of the one or more hydrogen storage tanks within the cargo bay extending parallel to the longitudinal axis (501) of the fuselage and lying in one or more planes (595, 597) extending across the width dimension of the cargo bay. The hydrogen storage tanks within the cargo bay have a common aspect ratio R in the range 4.2?R?25.7, allowing the volume of space with the cargo bay occupied by stored hydrogen to be maximised or approximately maximised.

Abstract: A computer-implemented method controls input of at least a portion of a first training data set into a first machine learning algorithm. The first training data set includes data quantifying damage to a first compressor and data quantifying a first operating parameter of the first compressor. The first machine learning algorithm is executed, and data quantifying the first operating parameter is received as an output of the first machine learning algorithm. The first machine learning algorithm is trained using the received data output from the first machine learning algorithm and data quantifying the first operating parameter of the first compressor. The trained first machine learning algorithm is configured to enable determination of operability of a second compressor of a gas turbine engine.

Abstract: An aircraft comprises a hydrogen-fuelled propulsion system, a plurality of like generally cylindrical hydrogen storage tanks and a conveying system arranged to convey hydrogen from the hydrogen storage tanks to the hydrogen-fuelled propulsion system. The aircraft further comprises a fuselage having a cargo bay (502) including one or more (510A-G) of the plurality of hydrogen storage tanks, the longitudinal axes (511A-G) of the one or more hydrogen storage tanks within the cargo bay extending parallel to the longitudinal axis (501) of the fuselage and lying in one or more planes (595, 597) extending across the width dimension of the cargo bay. The hydrogen storage tanks within the cargo bay have a common aspect ratio R in the range 4.2?R?25.7, allowing the volume of space with the cargo bay occupied by stored hydrogen to be maximised or approximately maximised.

Abstract: An aircraft comprises a hydrogen-fuelled propulsion system, a plurality of like generally cylindrical hydrogen storage tanks and a conveying system arranged to convey hydrogen from the hydrogen storage tanks to the hydrogen-fuelled propulsion system. The aircraft further comprises a fuselage having a cargo bay (502) including one or more (510A-G) of the plurality of hydrogen storage tanks, the longitudinal axes (511A-G) of the one or more hydrogen storage tanks within the cargo bay extending parallel to the longitudinal axis (501) of the fuselage and lying in one or more planes (595, 597) extending across the width dimension of the cargo bay. The hydrogen storage tanks within the cargo bay have a common aspect ratio R in the range 4.2 ? R ? 25.7, allowing the volume of space with the cargo bay occupied by stored hydrogen to be maximised or approximately maximised.

Abstract: A computer-implemented method comprising: controlling input of data quantifying damage received by a compressor of a gas turbine engine into a first machine learning algorithm; receiving data quantifying a first operating parameter of the compressor as an output of the first machine learning algorithm; and determining operability of the compressor by comparing the received data quantifying the first operating parameter of the compressor with a threshold.

Abstract: A computer-implemented method comprising: controlling input of data quantifying damage received by a compressor of a gas turbine engine into a first machine learning algorithm; receiving data quantifying a first operating parameter of the compressor as an output of the first machine learning algorithm; and determining operability of the compressor by comparing the received data quantifying the first operating parameter of the compressor with a threshold.

Abstract: An aircraft comprises a hydrogen-fuelled propulsion system, a plurality of like generally cylindrical hydrogen storage tanks and a conveying system arranged to convey hydrogen from the hydrogen storage tanks to the hydrogen-fuelled propulsion system. The aircraft further comprises a fuselage having a cargo bay (502) including one or more (510A-G) of the plurality of hydrogen storage tanks, the longitudinal axes (511A-G) of the one or more hydrogen storage tanks within the cargo bay extending parallel to the longitudinal axis (501) of the fuselage and lying in one or more planes (595, 597) extending across the width dimension of the cargo bay. The hydrogen storage tanks within the cargo bay have a common aspect ratio R in the range 4.2?R?25.7, allowing the volume of space with the cargo bay occupied by stored hydrogen to be maximised or approximately maximised.

Abstract: A computer-implemented method comprising: receiving an operability determination for a compressor of a gas turbine engine, the operability determination being determined using an output from a machine learning algorithm trained using data quantifying damage received by compressor blades of a compressor; determining one or more actions to be performed using the received operability determination; and generating control data using the determined one or more actions.

Abstract: A computer-implemented method comprising: controlling input of data quantifying damage received by a compressor of a gas turbine engine into a first machine learning algorithm; receiving data quantifying a first operating parameter of the compressor as an output of the first machine learning algorithm; and determining operability of the compressor by comparing the received data quantifying the first operating parameter of the compressor with a threshold.

Abstract: A computer-implemented method comprising: controlling input of at least a portion of a first training data set into a first machine learning algorithm, the first training data set including: data quantifying damage to a first compressor; and data quantifying a first operating parameter of the first compressor; executing the first machine learning algorithm; receiving data quantifying the first operating parameter as an output of the first machine learning algorithm; and training the first machine learning algorithm using: the received data output from the first machine learning algorithm; and data quantifying the first operating parameter of the first compressor, the trained first machine learning algorithm being configured to enable determination of operability of a second compressor of a gas turbine engine.

Abstract: A bladed disk may be arranged to rotate about an axis of rotation and including a rotor disk having an axial length extending from a first end to a second end, along the axis of rotation and a radial thickness extending between a first radius from the axis of rotation and a second radius from the axis of rotation, less than the first radius. The bladed disk may include a plurality of blades formed integrally with the rotor disk and arranged circumferentially around the rotor disk, and a first set of divides and a second set of divides, each divide comprising a partial break in the rotor disk extending axially from the first end of the rotor disk to the second end of the rotor disk and radially from the first radius to a third radius, less than the first radius and greater than the second radius.

Abstract: A bladed disk may be arranged to rotate about an axis of rotation and including a rotor disk having an axial length extending from a first end to a second end, along the axis of rotation and a radial thickness extending between a first radius from the axis of rotation and a second radius from the axis of rotation, less than the first radius. The bladed disk may include a plurality of blades formed integrally with the rotor disk and arranged circumferentially around the rotor disk, and a first set of divides and a second set of divides, each divide comprising a partial break in the rotor disk extending axially from the first end of the rotor disk to the second end of the rotor disk and radially from the first radius to a third radius, less than the first radius and greater than the second radius.

Abstract: A turbofan gas turbine engine (10) comprises a variable area exhaust nozzle (12) arranged at the downstream end of a casing (17). A control unit (66) analyzes the power produced by the gas turbine engine (10), the flight speed of the gas turbine engine (1) and/or the altitude of the gas turbine engine (10). The control unit (66) configures the variable area nozzle (12) at a first cross-sectional area (70A) when the flight speed of the gas turbine engine (10) is less than a first predetermined value. The control unit (66) configures the variable area nozzle (12) at a second, smaller, cross-sectional area (70B) when the flight speed of the gas turbine engine (10) is greater than the first predetermined value and the power produced by the gas turbine engine (10) is greater than a second predetermined value.

Abstract: A turbofan gas turbine engine (10) comprises a variable area exhaust nozzle (12) arranged at the downstream end of a casing (17). A control unit (66) analyses the power produced by the gas turbine engine (10), the flight speed of the gas turbine engine (1) and/or the altitude of the gas turbine engine (10). The control unit (66) configures the variable area nozzle (12) at a first cross-sectional area (70A) when the flight speed of the gas turbine engine (10) is less than a first predetermined value. The control unit (66) configures the variable area nozzle (12) at a second, smaller, cross-sectional area (70B) when the flight speed of the gas turbine engine (10) is greater than the first predetermined value and the power produced by the gas turbine engine (10) is greater than a second predetermined value.