Maj Teruhiko Kobayashi in his Ki-61. Note the 6 B-29 kill markings. The last one, crossed by a silhouette of his Ki-61, indicates his ramming of 27 January 1945.
Improvement of the basic model led to the Ki-100-II, with a turbocharged engine for high-altitude interception of the B-29 Superfortresses, but only three examples were built, and it never saw combat. Nakajima Ki-84
Ki 100 II with the turbocharged Ha 112 engine. Note the added scoops on the wing roots and the extra piping, half buried, under the fuselage. KI- 100 11 Ki-100-II (prototypes): engine Mitsubishi Ha-112-II Ru with turbocharger, 1,120 kW (1,500 hp). 3 built as such.