AIRCRAFT POWERPLANT WITH BOOSTED TURBINE ENGINE AND FUEL CELL SYSTEM

A powerplant for an aircraft includes a first turbine engine, a second turbine engine and a fuel cell system. The second turbine engine includes a second engine flowpath, a second engine compressor section, a second engine combustor section and a second engine turbine section. The second engine flowpath extends from a second engine flowpath inlet to a second engine flowpath outlet. The second engine flowpath inlet and the second engine flowpath outlet are each fluidly coupled with a flowpath of the first turbine engine. The fuel cell system includes a fuel cell, a fuel circuit and an air circuit. The fuel circuit extends through the fuel cell and is fluidly coupled with and upstream of a first fuel injector in the second engine combustor section. The air circuit extends through the fuel cell and is fluidly coupled with and downstream of a bleed from the second engine flowpath.