Abstract: A gas turbine engine comprises a fan, a core turbine engine coupled to the fan, a fan case housing the fan and the core turbine engine, a plurality of outlet guide vanes extending between the core turbine engine and the fan case, and an acoustic spacing. The fan comprises a plurality of fan blades that define a fan diameter and a BEAL. The fan case comprises an inlet and an inlet length between the inlet and the fan. The acoustic spacing comprises a distance between the fan and the plurality of outlet guide vanes, and in combination with the BEAL determines an acoustic spacing ratio of the gas turbine engine.

Abstract: Systems and methods are disclosed for estimating or determining a rate or an amount of fuel coke formation in a fuel system, such as of a gas turbine engine. The system is operable to control a rate of fuel coke formation. The system may include a sensor that measures an operating parameter associated with fuel coke formation in the fuel system. A controller is in communication with the sensor to receive the signal therefrom for determining an amount or a rate of fuel coking in the fuel system. Based on this determination the controller may adjust the rate of fuel coke formation by adjusting the operation of the turbine engine, a thermal management system of the turbine engine, or the fuel system.

Abstract: Systems and methods are disclosed for estimating or determining a rate or an amount of fuel coke formation in a fuel system, such as of a gas turbine engine. The system is operable to control a rate of fuel coke formation. The system may include a sensor that measures an operating parameter associated with fuel coke formation in the fuel system. A controller is in communication with the sensor to receive the signal therefrom for determining an amount or a rate of fuel coking in the fuel system. Based on this determination the controller may adjust the rate of fuel coke formation by adjusting the operation of the turbine engine, a thermal management system of the turbine engine, or the fuel system.

Abstract: A gearbox assembly includes a gearbox and a gutter for collecting a gearbox lubricant scavenge flow from the gearbox. The gutter is characterized by a lubricant extraction volume ratio between 0.01 and 0.3, inclusive of the endpoints. A gas turbine engine includes the gearbox assembly.

Abstract: A fuel system for a power generator using hydrogen fuel and a method of recovering a safety marker added to the hydrogen fuel. The hydrogen fuel may be stored in a tank and delivered, in at least one of a gaseous phase and a supercritical phase, to a power generator. The hydrogen fuel is delivered with a fuel delivery assembly and contains at least one safety marker when the fuel is in the fuel delivery assembly. The at least one safety marker is separated from the hydrogen fuel, using, for example, a separator. The at least one safety marker separated from the hydrogen fuel is stored in a safety marker storage tank. The safety marker may be a visual safety marker, such as a noble gas, or an odorant.

Abstract: A gearbox assembly for a turbine engine. The turbine engine includes a drive shaft and a fan shaft. The gearbox assembly includes a first gear, a second gear, an output, and a journal pin. The first gear is connected to the drive shaft. The second gear is supported by a planet carrier. The output is connected to the fan shaft. Torque is transferred from the drive shaft of the core turbine engine to the fan shaft through the gearbox assembly. The journal pin is inserted into the planet carrier. The second gear rotates about the journal pin. A coupling of the journal pin and the planet carrier is characterized by an interference ratio greater than a minimum interference ratio of 1.0e-5.

Abstract: A hydrogen fuel including a safety marker and a method and apparatus for adding the safety marker to the hydrogen fuel. The hydrogen fuel may be stored in a tank in a liquid phase and then heated to at least one of a gaseous phase and a supercritical phase. The safety marker may be added to the hydrogen fuel when the hydrogen fuel is in the at least one of the gaseous phase and the supercritical phase after heating the hydrogen fuel. The hydrogen fuel may be delivered in the at least one of the gaseous phase and the supercritical phase to a power generator, such as a gas turbine engine. The safety marker may be a visual safety marker, such as a noble gas, or an odorant.

Abstract: A fuel leak detection system for hydrogen fuel system including a monitored component. The fuel leak detection system including a sensor and controller communicatively coupled to the sensor. The sensor is positioned to monitor at least a portion of the monitored component. The sensor is configured (i) to sense a parameter corresponding to a hydrogen fuel leak of the monitored component and (ii) to generate an output. The controller is configured (i) to receive the output of the sensor, (ii) to determine, based on the output of the sensor, if a leak has occurred in the monitored component, and (iii) to generate an output indicating a fuel system leak when the controller determines that the leak has occurred in the monitored component. The monitored component may be a component of one of a fuel tank, a power generator, and a fuel delivery assembly.

Abstract: A fuel system for a power generator using hydrogen fuel and a method of recovering a safety marker added to the hydrogen fuel. The hydrogen fuel may be stored in a tank and delivered, in at least one of a gaseous phase and a supercritical phase, to a power generator. The hydrogen fuel is delivered with a fuel delivery assembly and contains at least one safety marker when the fuel is in the fuel delivery assembly. The at least one safety marker is separated from the hydrogen fuel, using, for example, a separator. The at least one safety marker separated from the hydrogen fuel is stored in a safety marker storage tank. The safety marker may be a visual safety marker, such as a noble gas, or an odorant.