top Pentagon official on Wednesday gave a tantalizing peek into several projects that not long ago were the stuff of science fiction, including missile-dodging satellites, self-flying F-16 fighters and robot naval fleets.

Though the Pentagon is not planning to build devices that can kill without human input, Deputy Secretary of Defense Robert Work hinted that could change if enemies with fewer qualms create such machines.

"We might be going up against a competitor that is more willing to delegate authority to machines than we are, and as that competition unfolds we will have to make decisions on how we best can compete," he said.

Work, who helps lead Pentagon efforts to ensure the US military keeps its technological edge, described several initiatives, including one dubbed "Loyal Wingman" that would see the Air Force convert an F-16 warplane into a semi-autonomous and unmanned fighter that flies alongside a manned F-35 jet.