If you thought that Asa meeting up with Keiichi at the end of the previous volume was going to be the start of this series moving on to bigger things, then you were right. ...From a certain point of view. That’s because we’re still in 1964 and the Tokyo Olympics are about to kick off! It’s going to be the event of the decade for Japan, and the government wants to make sure that nothing interferes with it. This includes the possibility of a kaiju attack. It’s what Kasuga’s shady government friend has recruited him and Asa for as they’re the only ones who a) have firsthand knowledge of it and b) can fly a plane. Believe it or not, they’re Japan’s best defense against Not-Godzilla.
As for what they’re supposed to do when they encounter it, your guess is as good as mine. It’s not something that happens in this volume, though. Vol. 3 is mainly a whole lot of setup to make sure that everyone is in place for what happens next and that we care about them when they get there. Which is why we get chapters devoted to seeing Shota practice his running and seeing Asa’s family deal with some bullies. These are fine, even though you can see mangaka Naoki Urasawa clearly pulling the strings behind each encounter. The same goes for all the encounters Asa has, be they explicitly plot-relevant (anything involving Keiichi or her new driver), or simply frivolous (the business involving her friends at school). My gut and the last page tell me that this will likely lead somewhere interesting. It’s just that if Urasawa was really bringing his A-game to this then all the string-pulling wouldn’t be so obvious.