The city was an important railroad junction and Hengyang Airport was used by USAAC General Claire Lee Chennault's Flying Tigers which were engaged in bombing operations of the Japanese homeland.
Three prototypes were ordered by the USAAC, but the company could only afford to build one, which never flew.
In 1935, Northrop had flown the Northrop 3A, a single-engined, single-seat monoplane with a retractable undercarriage, to meet a United States Army Air Corps (USAAC) requirement for a single-seat fighter.