F-190 and F-25 are the only two remaining fields from which twin-engine ac (bombers) can be launched by the enemy. I would encourage Frame 4 planners to look at "what's left" for the enemy, air field wise, in the last two Frames. "What if" more than one of the large fields might be closed? "What if" one large one and a couple of the smaller ones were possible? I didn't do my homework prior to starting this response, but it would seem that it "might" be possible (as it would be in RL) to deny the enemy the opportunity to have certain steps fly at all in Frame 5. It wouldn't hardly represent the "Spirit of the S3s", but it would theoretically be possible. (I'd be fairly certain that the combat engineers would somehow turn one or more of the remaining two-step fields into 3 step ones prior to Frame 5)
Alternately, IF the Frame Planners elected to attempt both F-190 and smaller field F-178, most people would suspect that in Frame 5 that the enemy would be forced to come at us exclusively in the South simply due to basing availability for their aircraft. Take a look at "what's left".
That's a "whole quarter" more than the "two cents" I wasn't asked for. Good luck, Sakai, I'm sure any plan you come up with will "work".
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