The term 'Plane on a Mission' can be summarized as a BOMBER, which is a six-letter word. A BOMBER is an aircraft that is used to drop bombs on enemy targets during wartime. Bombers are usually heavily armed and armored, and they are designed to fly long distances in order to reach their targets. During World War II, bombers were used extensively by both the Allied and Axis powers. Today, bombers are still used by many countries for military operations.