Tucked away inside the Defense Advanced Research Projects Agency's most recent budget proposal is a request for millions of dollars to explore what one could best describe as an unmanned flying gun capable of engaging airborne and ground-based targets. This comes around a year and a half after DARPA first announced it was working on what it called a "Flying Missile Rail." The system would carry its own air-to-air missiles and would be launched like a drone from under the jet's wing, after which they would fly off and engage aerial targets with their missiles. DARPA is asking for $13.27 million in its budget request for the 2021 Fiscal Year for the flying gun effort, which it has dubbed Gunslinger. The budget documents say that this is a new program and it is in no way related to the U.S. Navy and Marine Corps program of the same name, which developed a system to detect incoming hostile gunfire.

"Gunslinger program will develop and demonstrate technologies to enable an air-launched tactical range missile system capable of multi-mission support," the Gunslinger entry in DARPA's budget proposal says. "This system will utilize the high maneuverability of a missile system coupled with a gun system capable of scalable effects and engagement of multiple targets." The section does not give any specifics as to the overall size of the weapon system DARPA is envisioning or what type or types of guns it might be capable of carrying. It also does not say what types of aircraft would be capable of carrying these gun-armed "missiles" in the future, though it says that the plan would be to ultimately transition the project to the Air Force and the Navy.

DARPA The entry on Gunslinger from DARPA's 2021 Fiscal Year budget request.