Northrop N-9M

The Northrop N-9M was an approximately one-third scale flying wing aircraft with a 60-foot span, used to develop the full size 172-foot span Northrop XB-35 and YB-35 long-range heavy bombers. It first flew in 1942 and was the third in a lineage of all-wing Northrop designs that began in 1929, when Jack Northrop succeeded in early experiments with his single pusher propeller, twin-boom, stressed metal skin X-216H monoplane. The second was the dual-propeller N-1M of 1939 to 1941, and the letter M in the name stands for Model. Northrop pioneering work on all-wing aircraft eventually led Northrop Grumman to the B-2 Spirit stealth bomber, which entered United States Air Force inventory in 1989.