Air turbine start system

An air turbine starter system, the system comprising:

• an air turbine starter device comprising:
• a rotor arranged in a rotor cavity of a housing;
• the housing comprising a first manifold having a first manifold cavity with a first manifold port operative to direct a flow of first manifold compressed air to the rotor for rotation in a first direction;
• and the housing comprising a second manifold having a second manifold cavity with a second manifold port operative to direct a flow of second manifold compressed air to the rotor for rotation in the first direction, wherein the first manifold is larger than the second manifold;
• a first control valve operative to control the flow of first manifold compressed air to the first manifold;
• and a second control valve operative to control the flow of second manifold compressed air to the second manifold,
• wherein the air turbine starter is communicatively connected to a compressed air source supplying the first manifold compressed air and the second manifold compressed air,
• wherein the first manifold is connected in parallel with the second manifold between the rotor and the compressed air source,
• and wherein the rotor is mechanically linked through a gear assembly to a core of a gas turbine engine such that rotation of the rotor rotates a compressor and a turbine of the gas turbine engine.

A method for controlling an air turbine starter system having an air turbine starter device comprising:

• a rotor arranged in a rotor cavity of a housing,
• the housing comprising a first manifold having a first manifold cavity with a first manifold port operative to direct a flow of first manifold compressed air to the rotor for rotation in a first direction,
• the housing comprising a second manifold having a second manifold cavity with a second manifold port operative to direct a flow of second manifold compressed air to the rotor for rotation in the first direction, wherein the first manifold is larger than the second manifold,
• wherein the first manifold is connected in parallel with the second manifold between the rotor and a compressed air source supplying the first manifold compressed air and the second manifold compressed air,
• and the rotor being mechanically linked through a gear assembly to a core of a gas turbine engine such that rotation of the rotor rotates a compressor and a turbine of the gas turbine engine, the method comprising:
• closing a first valve that is operative to control the flow of first manifold compressed air to the first manifold of the air turbine starter device;
• and
• opening a second valve that is operative to control the flow of second manifold compressed air to the second manifold of the air turbine starter device, such that the flow of second manifold compressed air to the second manifold is operative to drive the rotor of the air turbine starter system to a first speed.