Ejector assisted compressor bleed

Apparatus for bleeding air from a low pressure stage of a multi-stage compressor in a gas turbine engine comprising:

• a shroud surrounding the low pressure compressor stage, said shroud being constructed with at least one bleed aperture;
• a manifold mounted on the shroud and enclosing a reservoir communicating with the bleed aperture, said manifold having at least one outlet passage communicating with said reservoir;
• an ejector nozzle mounted in the outlet passage of the manifold in a direction away from the manifold, said nozzle being connected to a source of bleed air from a high pressure compressor stage of the gas turbine engine, said nozzle being constructed and positioned within the outlet passage to draw air from the reservoir when high pressure bleed air flows from the nozzle;
• and
• means controlling the flow of high pressure bleed air through the nozzle.