Makes one wonder if the P-51H was such an improvement over the P-51D, why was it not considered suitable for combat in Korea? Hint, it was not because of the greater availability of the D Mustang.
ack-ack
Ok sorry to use wiki, but it makes some sense...
Wiki QuoteDuring the Korean War, F-51s, though obsolete as fighters, were used as close ground-support aircraft and reconnaissance aircraft until the end of the war in 1953[45]. Because of its lighter structure and less availability of spare parts, the newer, faster F-51H was not used in Korea. With the aircraft being used for ground attack, their performance was less of a concern than their ability to carry a load.