Carl Molesworth, author of the latest book in the Osprey 'Duel' series 'P-40 Warhawk vs Ki-43 Oscar' and several other authoritative CBI related titles, has very kindly sent to me and given me permission to post here this revealing photograph of Ki-84 Hayate of the 9th Sentai, probably taken at Nanking, China at the end of the war. In the background may be seen Ki-44 Shoki aircraft possibly from the same unit.
For years the design of the 9th Sentai tail marking has been questioned, despite being depicted in profiles and artwork, because of the apparent absence of photographic evidence. According to Minoru Akimoto the marking was representative of the historical spear of warrior Kiyomasa Kato during Japan's invasion of Korea around 1596 and the character 'na' from the name of the Sentai's first commander Lt Col Seisaku Namba. A simpler explanation is that the marking represents the Kanji character for '9' (with thanks to Katsushi Owaki).
The distinctive dark stain on the undercarriage cover was caused by the lowest sets of the ejector exhausts each side of the cowling but has been incorrectly interpreted as a painted marking in some profiles.
Image credit: ©Carl Molesworth 2008