Which Japanese fighter was the predecessor of the "Reisen?"
Mitsubishi A5M:  It was the world's first monoplane shipboard fighter to enter service and the direct predecessor of the famous Mitsubishi A6M "Zero". Mitsubishi A6M Zero:  The A6M was usually referred to by its pilots as the "Reisen" (zero fighter), "0" being the last digit of the imperial year 2600 (1940) when it entered service with the Imperial Navy.
i don't know