This is the shutter assembly from the pulsejet motor of a JB-2 Loon missile. Built by the Ford Motor Company for the U.S. Navy's Bureau of Aeronautics, the Loon was an American copy of the German pulsejet-powered V-1 or "Buzz Bomb" surface-to-surface missile used during World War II. The Loon was designed to carry a two-thousand-pound explosive payload to a maximum range of 150 miles. It could be launched from the ground, surface ships and submarines, or aircraft.
The Navy first test launched the Loon in October 1944, but its development came too late for active service in the war. This missile did, however, provide invaluable experience to the Navy and the Air Force in the development and handling of missiles. The Navy canceled the Loon program in 1950, replacing it with the faster and more powerful Regulus missile.