Sentence:  I am recommending additional acquisitions of the improved version of the B-52 ( the B-52 H with the new <WSD>turbofan</WSD> engine ) and procurement of the B-58 supersonic medium bomber , together with the supporting refueling tankers in each case . 
Meaning of the word marked with <WSD> tags:  a jet engine in which a fan driven by a turbine provides extra air to the burner and gives extra thrust