The General Atomics MQ-9 Reaper hunter/killer aerial drone better known for killing ISIS fighters in Syria, Afghanistan and Iraq now apparently has the capability to shoot down enemy aircraft approaching it from behind, or from the 6 o'clock position.

The U.S. Air Force recently revealed an MQ-9 had shot down a target aerial drone with an AIM-9X Sidewinder short-range air-to-air missile. It was another successful test towards the goal of deploying this unmanned combat aerial vehicle (UCAV) as an air-to-air combat fighter controlled by other manned aircraft such as Lockheed Martin F-35 Lightning II stealth fighters.

"Sept. 3, 2020, at Creech Air Force Base, Nev. The MQ-9 successfully employed a live air-to-air test of an AIM-9X Block 2 missile against a target BQM-167 drone simulating a cruise missile," said an announcement from the Air Force.

It isn't clear if this is the first shoot down of a drone by an AIM-9X Block 2. It also isn't clear where the target drone was in relation to the Reaper. The Air Force identifying the Sidewinder as an AIM-9X Block 2 is significant, however.

This version of the Sidewinder has a Lock-on After Launch (LOAL) capability allowing it to be launched first and then directed towards its target by an aircraft with the proper equipment for 360 degree engagements. Air Force warplanes with this equipment are the Lockheed Martin F-35 Lightning II and the Lockheed Martin F-22 Raptor, both of which are stealth fighters.

The 360 degree shoot down capability of the AIM-9X Block 2 allows it to attack an enemy aircraft behind the firing plane, or in any other position, as long as another friendly aircraft can vector the Sidewinder to the enemy target.

It's not known how many other drones Reapers have shot down at Creech, which is the center of these drone-on-drone combat tests. What's known is a Reaper first shot down another aerial drone with a missile some time in 2017. The Air Force only revealed this fact almost a year later. Military pundits called this first-of-its-kind achievement a watershed moment in the history of aerial warfare since it opens the door wider to drones replacing manned fighters in the future.

The revelation of this historic shoot down in 2017 was made only in September 2018 by Col. Julian Cheater, commander of the 432nd Air Expeditionary Wing (Hunters).  Col. Cheater said an MQ-9 Reaper launched a infrared guided AIM-9 against a "maneuvering target," or a small target drone. The missile completely destroyed the drone. This is the first time an unmanned aircraft had shot down another unmanned aircraft.

The 432nd flies only Reaper and RQ-170 Sentinel UCAVs. It's the first Air Force wing dedicated to unmanned aircraft systems. Some of its squadrons are now deployed to Afghanistan and Iraq.