Does 'He then discovered, to his surprise, that the Langley fighters were not headed north toward the Baltimore area as instructed, but east over the ocean.' exist in a separate context from 'The fighters were headed to Baltimore. ', without logical interdependence?
He then discovered, to his surprise, that the Langley fighters were not headed north toward the Baltimore area as instructed, but east over the ocean.###The fighters were headed to Baltimore. 