Hope that a traffic tower somewhere notices how low he was flying. He'll be grounded. 
Unfortunately, the airport that it comes out of is a small, privately operated little richmans airport. Boys and their toys, if'n ya know what I mean. 
And there are no others in the (relative) vicinity?
Not really, the nearest REAL air traffic control tower is at the Portland Maine Jetport. And their job is mostly to keep passenger and other large planes out of each others way. Any small planes tracked are of those that may be travelling some distance or have filed a flight plan. any small planes flying that low and not very far from their origins are not really tracked. The only exception would be if they wandered into the flight path of another plane. For somebody pretending to be a WW 2 flying ace and flying low, the only way I would have to do anything about it is to record their plane number and report it to police. And that would be a joke!
I like your idea of firing a rocket across his bow, a lot more.
It would take some small degree of finesse (calculating a predictable rocket launch) to get it into his view, safely, but funny. He might choose to go play somewhere else.
We have a small airport nearby also, but we also have quite a few open fields to fly over, where the risk to homeowners is minimal. They have just expanded the runway, though, and private Leer Jets can now land there. They are noisy, but at least they fly in a sane manner.
True it would take some finesse, but, I figure if he's that low and even sees it, he'll probably shit in his flight suit if it comes close enough. Plus it would be hilarious if he complained to the cops and then have to explain why he was flying so low to begin with to even be concerned with it.
They are supposed to fly at least a thousand feet above structures unless they have special clearance, like taking aerial photo's. This douchebag was going way too fast for that, more like he was doing a strafing run.
We have a lot of forests and mountains where he could have done this particular maneuvering, I mean there's a National Forest 5-10 minutes flight away from my house and three long lakes.
Testosterone poisoning, I guess.
