Marvel had the Phantom Eagle, which went pretty unnoticed until Garth Ennis wrote a miniseries on him earlier this year. It's... OK. A bit over-the-top, as far as that goes. It's called
War is Hell, the First Flight of the Phantom Eagle.
There have been three archive editions of the
Enemy Ace issues, which were spread out through several books. Two were full color (and pricey!) where the recent black and white one is more complete. The complete listing of available work is at
DCU | Graphic Novels
Titan has just reprinted the seminal 80's
Charley's War, an unflinching look at WWI ground combat.