PURPOSE: To raise reliability in emergency by inputting the power generated by two gas turbines to a common gear box, distributing the power to each power device, and supplying compressed oxidant in a storage container to a combustion chamber of one of the gas turbines.

CONSTITUTION: A mechanical gear box 10 for receiving rotary input of shafts 12, 14 and driving an electric generator 16, a fluid pump 18 and another attached device 20 is provided. Two turbines 22, 24 with the high pressure combustion gas generated in each combustion chamber 46, 60 and injected from nozzles 52, 66 as their power source are provided. The power generated by the first turbine 22 drives a rotary compressor 28, and rotates a shaft 12 via a planet gear box 40 and a clutch 42. The power generated by the second turbine 24 rotates a shaft 14 via a clutch 68. A storage container 56 for storing compressed oxidant is provided. To cope with emergency operation mode, the container 56 is connected to the combustion chamber 60 via a valve 58.