Is there any precedent in 40k background for air power (e.g. thunderbolts, lightnings or marauders) belonging to PDF or guard forces rather than Imperial Navy?
I've finally built up the courage to attempt to build and paint my Thunderbolt and want to mark it up as part of my Ultramar PDF force but other than Double Eagle (where a fighter wing was the guard / PDF for a particular world that had no land mass iirc) I'm not sure this would actually be allowed by the administratum.
Although I could build up a convincing argument for why Lord Macragge has managed to "borrow" a fighter wing for his PDF to use I thought I'd see if the combined fluff knowledge of these forums could help out!