Inspired by the Corsair-vs-Mustang thread, another question: What exactly needed the USN both types of fighter for, Hellcat and Corsair? Both were introduced at roughly the same time, and contrasted to a statement in the other thread, the Corsair saw service even a little earlier. According to Wikipedia, the Hellcat "accounted for 75% of all aerial victories recorded by the U.S. Navy in the Pacific." But the Corsair "quickly became the most capable carrier-based fighter-bomber of World War II. Some Japanese pilots regarded it as the most formidable American fighter of World War II, and the U.S. Navy counted an 11:1 kill ratio with the F4U Corsair." Both served as fighter-bombers, too. So what was the benefit of producing them both instead of concentrating manufacturers on one type only?