An air turbine starter comprising a housing defining an inlet, an outlet, and a flow path, a turbine having a rotor with circumferentially spaced blades extending into the flow path, a drive shaft operably coupled to and rotating with the rotor, and at least one vane located within the flow path, upstream of the blades. The at least one blade being defined by an acute axial angle and an acute tangential angle.

An air turbine starter comprising a housing defining an inlet, an outlet, and a flow path, a turbine having a rotor with circumferentially spaced blades extending into the flow path, a drive shaft operably coupled to and rotating with the rotor, and at least one vane located within the flow path, upstream of the blades. The at least one blade being defined by an acute axial angle and an acute tangential angle.

A disclosed drive assembly for an auxiliary power unit includes a first drive shaft driven by an auxiliary power unit, a second drive shaft driven by a first electric motor, a differential gear system including a ring gear driven by the second drive shaft, a and planet gears supported within a carrier attached to the ring gear. The first drive shaft and an output shaft are coupled to the planet gears and a generator is driven by the output shaft. The electric motor and the auxiliary power unit combine to drive the output shaft.

An air turbine starter that includes a housing. The housing can circumscribe a turbine coupled that is coupled to a gear train in a gear box via a drive shaft. The gear train can couple to an output shaft via at least a carrier. The air turbine starter can include at least a first bearing assembly and a second bearing assembly to rotatably support one or more of the drive shaft, the carrier, or the output shaft.

A system and method for predicting a remaining oil life of oil in a gearbox of an air turbine starter of a vehicle. The method includes generating a temperature data, generating an environmental data set by an environmental sensor, predicting a remaining oil life based on the temperature data set and the environmental data set and scheduling a maintenance event in response to the prediction of the remaining oil life.

A system and method for predicting a remaining oil life of oil in a gearbox of an air turbine starter of a vehicle. The method includes generating a temperature data, generating an environmental data set by an environmental sensor, predicting a remaining oil life based on the temperature data set and the environmental data set and scheduling a maintenance event in response to the prediction of the remaining oil life.

An air starter for an engine, such as a turbine engine, that includes a turbine for rotatably extracting mechanical power from a flow of fluid. The turbine includes a drive shaft that can be coupled to an output shaft to provide a rotational output. The interface between the drive shaft and the output shaft can be offset.

An air starter for an engine, such as a turbine engine, that includes a turbine for rotatably extracting mechanical power from a flow of fluid. The turbine includes a drive shaft that can be coupled to an output shaft to provide a rotational output. The interface between the drive shaft and the output shaft can be offset.

An air turbine starter that includes a housing. The housing can circumscribe a turbine coupled that is coupled to a gear train in a gear box via a drive shaft. A primary air flow path is defined between a primary inlet and a primary outlet. Air in the primary air flow path can flow into a secondary air flow path or rotate the turbine, that converts energy from the air flow to rotational mechanical energy. Air in the secondary air flow path can pass through at least a first cavity and first passage before rejoining the primary air flow or joining ambient air.

An air turbine starter that includes a housing. The housing can circumscribe a turbine coupled that is coupled to a gear train in a gear box via a drive shaft. A primary air flow path is defined between a primary inlet and a primary outlet. Air in the primary air flow path can flow into a secondary air flow path or rotate the turbine, that converts energy from the air flow to rotational mechanical energy. Air in the secondary air flow path can pass through at least a first cavity and first passage before rejoining the primary air flow or joining ambient air.