Sentence:  And there would be no chance of signaling them - without the Nernst generator Jack could not send a call powerful enough to get through all the static , and by the time he could rebuild his fusion power the skiff would <WSD>be</WSD> gone . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)