RAAF's Mustangs from 77 Squadron (which had been on duty with the occupation forces in Japan) initially provided much of the close air support for the beleaguered United Nations ground forces. Later re-equipped with the British-made Gloster Meteor jet fighter, 77 Squadron continued to operate in Korea as part of the United States Fifth Air Force. Although initially operating behind propellers, their work was professional, effective, and ... appreciated.
Day two of the Sukchon drop. We were making our way up a hill, trying to stay out of the line of fire of a NK self-propelled 76 that kept lobbing rounds in our direction. Really couldn't tell if we were the targets or not, since the rounds seemed to be going over us and not into us. Perhaps the SP could not depress his gun enough due to being dug in or perhaps he was just letting us know he was still in the war. After a time of hitting the dirt and climbing, repeat, repeat, the Platoon Sgt. got a little weary of the game and got on the radio to see if there was any air support in the area. Right away we had contact with a voice speaking with a decidedly English accent, informing us that they were almost over the area and could we put out some smoke so they could spot our position. We did and in short order a flight of Mustangs with Australian markings barreled by very close overhead.
Almost immediately our Aussie friend inquired if we had our air strike panels out. We didn't, what with climbing and ducking we had forgotten. "I say, mates, if we don't see your panels, we don't really know if you threw the smoke or not. From up here all you people look the same to us." Out went the panels, quickly! Telling the pilots the general direction we figured the rounds were coming from, they circled at a higher altitude until the SP fired again. "OK, Yanks, we have him spotted, pull in your heads and we will fix the bugger." With that the entire flight peeled off and came down firing all the ordinance they had. One pass and we could hear the SP self-destructing in the distance. We sincerely thanked our Aussie mates and they gave us a victory roll as an acknowledgment. For air support, those countries flying the P-51's were far and away the most efficient. The prop jobs could get in and out of the valleys and hills quite easily while the jets just moved too fast to negotiate the terrain. In my personal experience, the Aussies and Brits and South African pilots were very courageous and totally lacking in caution. If you had a target for them, they took it out and were happy to help.