The Akutan Zero, also known as Koga's Zero (古賀のゼロ) and the Aleutian Zero, was a type 0 model 21 Mitsubishi A6M Zero Japanese fighter aircraft piloted by Petty Officer Tadayoshi Koga, that crash-landed on Akutan Island, Alaska Territory, during World War II. It was found intact by the Americans in July 1942 and became the first Zero acquired by the United States during the war that could be restored to airworthy condition. It was repaired and flown by American test pilots. As a result of information gained from these tests, American tacticians were able to devise ways to defeat the Zero, which was the Imperial Japanese Navy's primary fighter plane throughout the war.

The Mitsubishi A6M "Zero" is a long-range carrier-based fighter aircraft formerly manufactured by Mitsubishi Aircraft Company, a part of Mitsubishi Heavy Industries. It was operated by the Imperial Japanese Navy (IJN) from 1940 to 1945. The A6M was designated as the Mitsubishi Navy Type 0 carrier fighter , or the Mitsubishi A6M Rei-sen. The A6M was usually referred to by its pilots as the Reisen, "0" being the last digit of the imperial year 2600 (1940) when it entered service with the Imperial Navy. The official Allied reporting name was "Zeke", although the name "Zero" was used colloquially as well.