Under the company designation NA-44, North American developed a light attack version of its classic BC-1/AT-6 advanced trainer design. This prototype was powered by a 785-hp Wright R-1820-F52 Cyclone engine and was of stressed-skin construction throughout. Forward-firing armament comprised two machine guns in the cowling and one in each wing, while provision was made for a gun firing aft from the rear cockpit. Up to 400 lb of bombs could be carried.

An order for 10 attack aircraft came from Siam, and these were built under the company designation NA-69. At the outbreak of hostilities with Japan, these aircraft were requisitioned by the USAAF and hurriedly put into combat in the Philippines. The designation A-27 was applied, with the serials 41-18890/41-18899.