By late November 1943, the 9th FS was declared as operational (after receiving P-47). The commanding officer of the 9th, Maj. Jerry Johnson, would get the squadron's first victory with the P-47. Yet, it was a victory that should have been passed up. Taking an opportunity to fly with Kearby's 348th FG, Johnson accompanied them on a sweep over Finschhaven (New Guinea). Spotting a radial engine aircraft flying about 3,000 feet above the jungle canopy, Johnson raced down and put a burst into the plane's engine. A parachute was observed.
Upon his return, Johnson was deeply disturbed to learn that the radial engine aircraft was not Japanese. Johnson had shot down an RAAF artillery observer flying an Australian built Wirraway (the Wirraway was essentially, a modified North American BT-9 which was the predecessor of the AT-6 and SNJ advanced trainer. Wirraways were built, under license, by Australia's Commonwealth Aircraft Corporation). The pilot of the Wirraway had escaped serious injury. Nonetheless, he was sufficiently rattled and angered to file a complaint with the 5th Air Force command. Johnson, in a successful effort to make amends, hand carried a case of bootleg gin to a very forgiving Flight Officer R.M. Stewart. 5th Air Force legend has it that General Kenney personally provided Johnson with the alcoholic bribe.
Source:
http://home.att.net/~historyzone/Sev...Republic6.html