A 40mm canister is an unusual form factor for a quadcopter, but not an unproductive one. Like the endless variation on a simple form seen in beetles, quadcopters combine four rotors, internal sensors and remote direction with the adaptability to fit into any ecological niche.
Drone 40, produced by Melbourne-based defense technology firm DefendTex, is a drone whose niche involves a 40mm grenade launcher. It is a range expander for infantry, a new and novel loitering munition, and a testament to the second-order effects of a thriving drone parts ecosystem.
Drone 40 was created as a solution to the problem of range; specifically, the problem of a range disparity between the infantry weapons carried by Australian infantry, which are accurate to about 500 meters, and the AK-74s carried by adversaries, which can reach out to 800 meters (though the accuracy at that range is disputed). Even if the fire is just suppressing fire, Australia was looking for a way to let its infantry fight back, but not one that required changing the gun or adding a lot more weight to what soldiers were already carrying.
“The only thing that we had in the infantry kit with any utility was a 40 millimeter grenade launcher,” which led to the design of the Drone 40, said DefendTex CEO Travis Reddy. Rather than overtaxing the launcher with a medium-velocity round that could travel the distance needed, the launcher would instead give a boost to a drone-borne munition that would then fly under its own power the rest of the way to the target.
The overall appearance of the Drone 40 is that of an oversized bullet. Four limbs extend from the cylindrical body, with rotors attached. In flight, it gives the appearance of a rocket traveling at perpendicular angles, the munition suspended below the rotors like a Sword of Damocles. It is a quadcopter, technically.
Drone 40 is a loitering munition, for a very short definition of loiter. When carrying a 110 gram payload, it can fly for about 12 minutes. The person commanding the Drone 40 can remotely disarm the munition, letting the drone land inert for later recovery. When not carrying an anti-personnel or anti-tank munition as payload, it can be outfitted with a sensor. For an infantry unit that wants to scout first, fire later, the sensor module can provide early information, then be swapped out with a deadly payload. Beyond Australia, the company envisions providing the Drone 40 to the Five Eyes militaries.
The drone’s video streaming can transmit 10 km over direct line of sight. Drone 40 can also record video and retransmit it when it comes within range, or it can take still images. With the radio frequency relayed by another aerial system, that range can be expanded. Using GPS, the drone can follow a waypoint plotted course to a target, or it can use its own synthetic aperture radar to identify and track a target. Reddy says it can distinguish the radar profile of, say, a T-72 tank, and then follow it autonomously.
Drone 40 is designed to fly with minimal human involvement. The unit’s development was largely funded in collaboration with Autonomous Systems Collaborative Research by the Australian government, and the drone can work collaboratives, with multiple Drone 40s flying together and operating off the sensor data from a single ISR drone in the swarm. Most of the flying, identifying and tracking of targets is done autonomously; however, human control remains an essential part of the machine’s operation.
“The Department of Defense has very strict rules around any use of autonomy in the battlefield,” says Reddy. “We always have to have either man in the loop or man on the loop. The weapon system will never be autonomous, fully acquire and prosecute target without authorization and confirmation from the human.”
The autonomy is there, in a sense, to pass off the task of flying a drone into position and only task the operator with making a call once the drone is in place.
“If there’s someone flying this thing or looking at the video feed, they’re not in combat and someone else is not in combat because they have to be protected at that point in time,” says Reddy. “Everything we do is trying to ensure that we have almost fire and forget, just a reminder when it’s on station or it requires a decision to be made; the rest of the time, the operator is in the fight.”
To make Drone 40 work at the small size and desired price point, its makers had to lean on the commercial drone market. Existing versions, Reddy says, cost less than a $1,000 apiece, with a goal of getting the cost down to around $500.
“To hit the price point that we are using, we are heavily leveraging the current drone market. We have companies, large companies that sink hundreds of millions of dollars into R&D and we can leverage that investment,” says Reddy. “If we wanted to design a radar on a drone ourselves, it would cost us many millions of dollars to achieve and end up in a price point of $10,000 to $15,000 a unit. Instead we let the automotive industry spend all that money and now they’re producing chips that are in the tens of dollars.”
Drone 40 is also designed to be scaled up. DefendTex is working on Drone 81, a larger round designed to work with mortar tubes, and there are other drone models in the works matched to specific munition sizes. If the iteration is successful, it will create a whole arsenal of possibilities for range-expanding munitions that fit into existing platforms.
“They’re designed to be low cost and disposable; that’s the key,” said Reddy. “If it doesn’t come back, it doesn’t matter.”