FIELD: aircraft industry. SUBSTANCE: power plant with additional gas-turbine engine for air starting system and ventilation and air conditioning system of cookpit and/or passenger cabin of aircraft is designed for starting of at least one main propulsion gas-turbine engine and for ventilating and air conditioning of cockpit and/or aircraft cabin at ground hold before takeoff. Plant has second additional gas-turbine engine with pipeline for taking for taking off air from compressor smaller by order of power than above indicated additional gas-turbine engine which is provided with starting turbine. Air takeoff pipeline of second additional gas-turbine engine is connected by means of two-position valve to air conditioning system and starting turbine of additional gas-turbine engine. Two position valve can be made either with one locking member or with two locking members, either with hole in central zone of locking member, or with slot over its periphery. Additional gas-turbine engines have common oil and fuel systems. EFFECT: reduced consumption of fuel, increased reliability of bearings. 5 cl, 5 dwg
