Early in 1941, when China’s fortunes were at their lowest ebb, Maj Gen Chu Gen-Chia, Chief of the Air Force Technical Bureau, initiated the design of a single-seat fighter monoplane powered by a 1,200 hp Pratt & Whitney R-1830-S1C3-G Twin Wasp radial engine and based broadly on the Curtiss Hawk 75A, but utilising indigenous materials. It was proposed that this, the X-PO, should be built in series at the Military Aircraft Factory at Kunming which was, at that time, idle. The X-PO was of metal construction with plywood skinning and featured inward-retracting main undercarriage members, large metal-skinned flaps and a centreline bomb rack to enable it to fulfil a secondary role of dive bomber. It was proposed that an unspecified cannon armament be mounted in underwing fairings. The prototype X-PO was flown at Kunming in 1942, but, in the meantime, US entry into WWII and the consequent release of supplies of fighters to China had removed the need for indigenous fighter manufacture and further development was discontinued. No data relating to the X-PO would appear to have survived.