Air Fortress, the Japanese NES version, shares core gameplay similarities with other regional releases, focusing on vertical scrolling shooter action.  Specific details on the Japanese version's potential differences from other releases (like enemy variations, level design, or even the soundtrack) would require more in-depth analysis.  The developer of the Japanese version is likely different from those who handled other regional ports.   The game would have been released in Japan within the NES's popular period for shoot 'em ups.

Air Fortress (Japan)

Ai Senshi Nicol (Japan)