Patent ID: 11859563
Assignee: PRATT & WHITNEY CANADA CORP.
Field: Transport (Mechanical engineering)
Classification: CPC F  B  Y | IPC B  F

Claim 11:
12. An aircraft, comprising:
a first engine having a bleed air system with a first common bleed air conduit, the first engine having an active mode when the aircraft is in flight at an altitude above ground;
a second engine having a main gaspath extending through a compressor section, a combustor, and a turbine section, the second engine having a secondary air system outside the main gaspath and including one or more of a sealing system and a lubrication system, the second engine having an active mode when the aircraft is in flight at the altitude above the ground and a standby mode when the aircraft is in flight at the altitude above ground, a power output of the second engine greater in the active mode than in the standby mode, in the standby mode, the second engine is operating, receives a fuel flow, and provides substantially no motive power to the aircraft;
at least one control valve disposed fluidly between the first engine and the second engine, the at least one control valve operable to:
i) fluidly connect the first common bleed air conduit of the first engine to the secondary air system of the second engine when the second engine is in the standby mode and when the first engine is in the active mode; and
ii) fluidly disconnect the first common bleed air conduit from the secondary air system of the second engine when the first engine and the second engine are in the active mode;

a source of pressurized air that is external to the first engine and/or to the second engine, the source of pressurized air being selectively fluidly connectable to the bleed air system of the first engine and/or of the to the secondary air system of the second engine;
a conduit fluidly connecting the at least one control valve to the compressor section of the second engine; and
a valve fluidly connected to the conduit, the valve configured for forcing the pressurized air received from the at least one control valve to bypass the gaspath of the second engine and to flow in the secondary air system of the second engine.