Planes That Never Flew is a Discovery Channel documentary series about experimental aircraft projects that never flew. Over four one-hour episodes, the series examined the history behind aborted projects to build two jet fighters, a supersonic transport, and a nuclear-powered long range bomber.

From the first men in their flying machines to World War One, from the first Atlantic crossing to the supersonic era, this is the story of the most daredevil challenges the world has ever known, braved by the men and women who wrote the history of human flight.