Abstract: Undesirably low efficiencies in a gas turbine engine of the sort having a radial compressor may be increased by forming the compressor with radially inner, high pressure ratio blades (16) and radially outer, low pressure ratio blades (18). The low pressure ratio blades (18) may discharge to a receiver (38, 40) for relatively low pressure air which in turn may be utilized as bleed air (FIG. 3) or as thrust (FIG. 2) as desired or even multi-staged with the high pressure blades (FIG. 4). The high pressure ratio blades (16) discharge to a receiver (48) which is in fluid communication with a plenum (54) to provide combustion air to a combustor (56) which in turn produces gases of combustion to drive a turbine wheel (66). By utilizing high pressure air from the high pressure ratio blades (16) for this purpose, engine efficiency is maximized.