Get ready to shrink the drone war. The Army and Marine Corps’ medium-sized spy drones may soon become killers, thanks to a successful flight test by a mini-drone strapped with a 12-pound bomb.

Raytheon, the defense giant, has been working since 2009 on what it calls a Small Tactical Munition — as the name suggests, it’s a bomb tiny enough to attach onto the military’s fleet of small to medium drones like the Shadow. Weighing 12 pounds and standing 22 inches, the guided munition has the potential to expand the drone war dramatically, giving battalion-sized units that fly small drones the ability to kill people, like the remote pilots who fly the iconic Predators and Reapers do.

Now Raytheon announces that on Sept. 16, a Cobra drone (the company’s in-house equivalent of a Shadow) flew over the Yuma Proving Ground in Arizona carrying the latest, lightest, smallest model of the Small Tactical Munition for the first time. The flight lasted an hour. It didn’t actually fire the munition at a target. (You’ll notice there are no fins on the missile, pictured above, although the design includes fold-up fins.)

Even though the munition is still a ways away from actually being used by the Marines — whose request to weaponize the Shadow has prompted these tests — it’s the latest milestone for the ongoing trend of miniaturizing killer drones. And there are many paths in development for micro-killers. A California company called Arcturus has built its own small, 17-foot drone that it claims can fire a 10-pound missile called the Saber. More recently, the industry leader in miniature drones, AeroVironment, rolled out an alternative model for small armed drones. Its diminutive hybrid of drone and missile, called the Switchblade, is designed to be carried in a soldier’s backpack until it’s launched into the sky on a kamikaze mission. Yet another design is to launch a deadly mini-drone from inside a larger drone, Russian-doll style.

The Small Tactical Munition keeps it simple. It’s designed to be carried by AAI’s Shadow — which means that it’s not using a boutique or unfamiliar model for shrinking the drone war. It would instead put a tiny missile on proven drones that the Army already possesses. While a Predator is about 27 feet long, with a 55-foot wingspan, a Shadow is smaller than 12 feet long, with a 20-foot wingspan.

But it’s about more than just shrinking the drone war. A battalion that uses a Shadow for aerial surveillance might not have to rely on higher headquarters — or its Air Force partners — for close air support if it can strap a bomb the size of a dumbbell to the wings of its drone. That could mean a big change in small-unit autonomy and tactics.

But the Army and the Marine Corps have been working to weaponize the Shadow since 2008, and nothing’s gotten out of the testing stage so far. The Air Force has its own fleet of ever-tinier drones, some even shaped like insects. If Raytheon can sell the military on its mini-bomb — especially considering that the cash-strapped military is going to be hard up for major new weapons purchases — it may only be a matter of time before the makers of killer drones start thinking even smaller.

Photo: Raytheon