Born in Richland, Washington. Captain Duncan was the starboard pilot of a C-130 stationed at Rhein-Main Airbase, Germany. He was a crewman aboard a U.S. Air Force reconnaissance aircraft from the 7406th Support Squadron, a C-130, tail number 60528. His aircraft was shot down by Soviet MiG-17s over Soviet Armenia on 2 September 1958. He and 16 other men were killed in the subsequent crash. Interred 2 September 1998.