Enlarge / In this video frame from ULA's live broadcast, three RS-68A engines power the Delta IV Heavy rocket into the sky over Cape Canaveral, Florida. (credit: United Launch Alliance) The final flight of United Launch Alliance's Delta IV Heavy rocket took off Tuesday from Cape Canaveral, Florida, with a classified spy satellite for the National Reconnaissance Office. The Delta IV Heavy, one of the world's most powerful rockets, launched for the 16th and final time Tuesday.