Okay, this one's a girl from a doujin set way after Jet Age - but one who could conceivably fit into the series proper on badassness alone.

MFI-9b Malmo
While P-40's black-Irish aesthetic is built around being down on the farm, to say nothing of built full stop, little mixed-race Fly Girl 9b (Swedish and Igbo, the combination you never knew you needed) is skinnier, flatter, and generally shrimpier, looking rather young for her age. Indeed, she looks roughly like a charity case - while people say Zero/Mozzie/Insert Anyone Else Here are too skinny, 9b looks as if she has some kind of horrible eating disorder. Saying whether she does or not constitutes MAJOR spoilers for the doujin in question, so I'll leave it at that. However, her most distinguishing feature, other than her hubcap-size flattened headscarf thing, is the enormous rocket launcher she carries everywhere she goes, decorated with a red, black and green roundel and a stylised python.

Why do I bring up her badass credentials? She's a prop-driven trainer aircraft lower and slower than anything else in the setting, and she takes on MiG-17. You know, the scariest and craziest of the scary crazy Russians? Yeah, she gonna fry, right?

Wrong.

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"She's old, she's lame, she's barren too, // "She's not worth feed or hay, // "But I'll give her this," - he blew smoke at me - // "She was something in her day." -- Garnet Rogers, Small Victory

FiMFiction.net: we might accept blatant porn involving the cast of My Little Pony but as God is my witness we have standards.

MFI-9bs are also called the Biafran Babies, and really did take down Nigerian MiGs. Also a couple of the Il-28s. They were the first MiniCOIN planes, they really did have a couple of rocket launchers nailed to the support struts, and generally speaking they were too awesome to be on the losing side. I smell Corwin's OC...