In 1934 in response to the lack of popularity of their Model 247, Boeing proposed a bomber version, known as the Model 249/YB-16, to the US Army Air Corps. The USAAC loved the Idea of a light/medium bomber to replace the already outdated Martin B-10s. Boeing then produced the B-16 Flying Citadel, out of their Redmond, Washington plant. The first squadrons to receive the new bombers were the 17th and 47th Bombardment Groups, stationed at McChord Army Air Field, Washington. Boeing also marketed their new bombers to several other countries and found buyers in the Spanish Republic, who desperately needed "modern" bombers in their civil war, and after the success of the type in the SCW, Poland, China and Finland made purchases of the bombers. The Polish Company PZL even obtained a license to build the bomber for Poland, but only a little more than 15 were produced by the start of WW2, and none of the Polish models survive today. In early 1940 the RAF was also desperate for bombers from the US and ordered a modified design called the Redmond, in honor of the main plant where they were being produced. It featured a slightly different turret, and .303 cal machine guns instead of the US .30 cal machine guns. In late 1940 Boeing released the B-16C, with newer engines, a newer turret and moved forward, .50 cal machine guns, as well more of them learned from lessons thus learned in WW2. These would be the last model of the B-16s produced for the USAAC/F as Boeing was ordered to drop the development in favor of developing better B-17s, which were needed in Europe. USAAF B-16s saw service in all theaters of the war, from the Attack on Pearl Harbor to the Fall of Nazi Germany. They were hastily retired after the war as they were no longer needed, most were sold off to "Banana Republics", or scrapped.