Yeah, the P-51 especially was tough.
A lot of people guessed 0 for the female aces, probably because they were Russian and that generally contributes to it not being that well known, at least among the average Joes in the US and Western Europe (for that matter, how many know that the Red Army employed women as actual infantry combatants and snipers?). Sadly, they were also killed in action in 1943. I THINK one of the women was named a Hero of the Soviet Union after her death.