I'm confused by "year to date"...
(slow brain in the morning). Didn't Lusche already posted that the P51 held the highest K/D?
No, I did not, mostly because the P-51 hasn't the highest K/D at all. Planes like the Me 262, Tempest or F4U-4 are still quite ahead

But Chalenge was asking for the pilots with the best K/D in each plane. And that I do not know. I could find out, but that would take quite a lot of effort which I'm unable (or unwilling?) to do right now.
Edit:
I might add that pure K/D alone doesn't interest me very much, as it can be gamed or be the result of a single sortie ever with just incredible luck.
