Development of the BQ-3 began in October, 1942, under a program for the development of "aerial torpedoes", later and more commonly referred to as "assault drones", that had been instigated in March of that year. Fairchild was awarded a contract for the construction of two XBQ-3 prototypes, based largely on the AT-21 Gunner advanced gunnery trainer already in United States Army Air Forces service.[1]
The XBQ-3 was a twin-engined, low-wing aircraft, fitted with retractable tricycle landing gear and a twin-finned empennage; although the aircraft was intended to be operated by radio control with television assist, a two-seat cockpit was included in the design for testing and ferry flights.[2] Power was provided by two Ranger V-770 inline piston engines of each;[3] up to of explosives could be carried by the aircraft in unmanned configuration.[2] Like the contemporary Fleetwings BQ-2, the aircraft would be destroyed in the act of striking the target.
The first flight of the XBQ-3 took place in July 1944;[1] later that month, one of the prototypes was severely damaged in a forced landing.[4] Despite the accident, flight testing continued; however, the assault drone was determined to have no significant advantage over conventional bombers, and advances in the field of guided missiles were rapidly rendering the concept obsolete.[5] As a result, the program was cancelled towards the end of 1944.[1]