The nozzles turn (vector) the thrust about 9 degrees relative to engine centerline, but I was told that it was that way to align the thrust through the c.g.. Then there would be no pitch change with thrust. I think the critical thing was on "go around" there would have been a lot of pitch trim adjustment required at a critical time when the engines spooled up and control power low. It is also difficult to rotate the aircraft for takeoff without the vector, requiring more runway to get to rotation speed. Does this sound rational, or have I been misinformed?
I don't have an A-10 three view but the incidence of the horizontal tail relative to the wing (Is it called decalage, or pitch dihedral or something?) is very large compared to anything else around. They even had to increase the nose down incidence of the horizontal tail during the prototype phase. You can tell on the prototypes that the vertical fins look rotated forward a smidge. The camber in the wing is like permanent flaps that always want to pitch the nose down. The horizontal tail load increases a lot with speed in order to trim the cambered wing. The tail incidence selected, I figure, is the best compromise that lets the elevator be neutral for normal cruise speeds.
Mc/I + P/A
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