FIELD: rocket engines. SUBSTANCE: invention relates to operation of liquid-propellant rocket engine with turbopump delivery of oxygen-methane propellant with part of expendable methane propellant used as cooling agent for direct-flow cooling of chamber. Said cooling agent, after using, is mixed with remaining mass of propellant, pressure of mixture is raised and mixture is fed into gas generator for combustion with part of oxygen oxidizer for getting recovery gas used on turbine and then waste gas is afterburned in chamber with remaining mass of oxidizer. Cooling agent, before mixing with remaining mass of propellant, is cooled by heat exchange with oxygen oxidizer, and part of propellant is used to create curtain cooling of chamber by delivering cooling agent to inner wall of chamber through provided belt of holes. EFFECT: increased specific thrust impulse of rocket engine. 2 cl, 2 dwg
