The last Ki-46 aircraft depicted in the air to air footage at the end of the video is a very rare Army Type 100 Command Recon plane Model III Kai (Ki-46 III Kai). This is showing the two 20mm nose cannon but not the upward firing dorsal 37mm cannon. The unit operating this fighter late war was the Dokuritsu Dai 16 Hikotai. It's possible a small number were sent to Manchuria to evaluate operations in the freezing conditions found there and to thwart the B-29 raids from China.
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