The Q series became the most numerous and advanced of all the Airacobra family. It was a direct successor of the N series. The whole propeller-engine group remained unchanged: the Allison V-1710-85 engine, the reduction gear, the elongated shaft and the Aeroprop type propeller. Because of this, the flight characteristics remained virtually unchanged. However, a more efficient four-bladed propeller was fitted to the series from Q-21 to Q-25.
The differences between the various Q series consisted mainly of the search for the optimum combination of armor protection and internal fuel tank capacity. Takeoff weight, range and load varied from version to version. Altogether, beginning with Q-1 and ending with Q-30, eight series of the fighter were built, to a total number of 4699 aircraft. Of these, 3291 were exported to the USSR. Furthermore a few reconnaissance versions of this aircraft, fitted with photo-cameras, were built on the basis of the Q series.