Smaller is better: the increasing importance of nano-UAV technology

The first unmanned aerial vehicle (UAV) flown in warfare, according to the strictest definition of the term, was unleashed by the Austrian Empire in 1849. Venice – formerly an imperial fief – was in rebellion and, placed as it was on wooden piles in a lagoon bordered by flat land, eluded attempts by the Austrian army to recapture it.

So a new plan was developed. On 22 August, Venetian citizens craned their necks towards the clouds to glimpse more than 200 teardrop-shaped balloons, each dangling 33 pounds of ordnance where their baskets should have been. Most of these gasbags carried a time charge, but others were connected to operators on the other side of the lagoon, by means of an isolated copper wire. Within half an hour, Venice would be ablaze. 

Although strictly speaking only a spiritual ancestor to the likes of the MQ-1 Predator, the Austrian attacks were proof of the value of an unmanned attack being directed remotely, and with a measure of precision, against an enemy position. Nowadays, complex UAV systems can fly for days on end, humming softly over enemy positions while being controlled thousands of miles away in an air-conditioned control box.

However, the use of drones in combat has largely been confined to two main areas: targeted assassination and reconnaissance. Recent years have seen a marked change in this dynamic. Spurred in part by the technological advances made in the development of commercial UAVs – the latest models routinely reach speeds of up to 10m/s with a communications distance of just under a kilometre – Western militaries have been seduced by the prospect of making their own drones smaller, lighter and more manoeuvrable.

Combat situations

One of the most obvious areas on the battlefield where a machine like this can make a difference is in combat patrol. With living memory largely defining the patrol as a foray into territory held by insurgents who strike from behind cover, before melting away into the terrain, having the ability to fully perceive the combat space beforehand could make all the difference between a successful repulse of the enemy and calling in a medevac.

“Nano UAVs are a tool that will give a patrol the ability to search an area in relative safety before they move in themselves,” says Staff Sergeant Jarle Mossing of the Norwegian Army, whose squad has experimented with several nano-UAVs in training exercises. Using the third-person view that a nano-UAV system can provide, the patrol can then follow through on any last-minute changes they want to make to their mission plan, including altering their route to avoid unwanted resistance or obstacles that might place the squad in greater danger over time. “Missions in urban areas, as well as in terrain that does not allow the patrol to get information about the current situation before they are standing in it, can now be conducted more safely than before,” says Mossing.

The current model adopted by the Norwegian army is the PD-100 Black Hornet II, developed by Prox Dynamics. Resembling a grey dictation machine with a tiny black eye and a set of rotor blades, the model only weighs 18g and can stay up in the air for up to 25 minutes. Its tiny camera can be used day and night, and the nano-UAV is able to resist strong winds that would thwart the use of many of its cousins in the commercial sector. That said, there are limitations, the first being battery capacity.

“You can easily fly out to 1.6km, as the specifications state, but doing so means that you must return home almost instantly when you reach that range,” says Mossing. “Weather also needs to be taken into consideration when flying out to these types of ranges. Often, the further you fly, the higher you need to ascend in order to have a line of sight between the UAV and the ground control station. Moreover, the higher you are, the greater the chance of strong winds, and this will also have an impact on how far you can travel to and fro the target.

“The closer you are in launching the UAV to the target of interest, the more playtime you have. All in all though, the use of the PD-100 in close proximity will give the user a vital tool on any given mission, in covering blind spots, close target recce, or just giving the user some eyes on what is behind the wall they are using as cover.”

Even so, if the enemy decides to take its own precautions, such as jamming the signal to the UAV, there isn’t much that can be done. “When it comes to an opponent that has access to nano-UAVs, he must be treated like an opponent that has access to the same type of equipment, only of a higher class,” Mossing explains. “One must remain mobile, and if you have to be static, use camouflage and trees. Most importantly, the squad must be spread out. Sooner or later, you will be spotted.”

On manoeuvres

The Norwegian Army is not the only military force that has shown interest in deploying nano-UAVs into the combat space. From 2012 onwards, the British Army deployed them in Afghanistan, and the Russian Armed Forces have recently announced their own interest in developing a similar system to the Black Hornet.

If it weren’t for the fact that the PD-100 is hand-made – a single kit costs the British Army $200,000 – it would have been very likely that the US army might follow suit. In the event, however, the US military chose to develop its own system, and since then, Phil Cheatham and his colleagues at the Manoeuvre Centre of Excellence (MCoE) at Fort Benning, Georgia, have been tasked with making sure its comparable soldier-borne sensor (SBS) will become deployable by 2018.

The capabilities of the SBS are intended to differ from that of the Black Hornet in several key respects. Drone and control system have been mandated to weigh no more than 150g, and the UAV itself should be able to fly within 60 seconds of being taken out of its pack and fly for 15 minutes straight with a maximum range of 1.2km. Its camera, meanwhile, should be able to spot a person from over 20m away. Above all, however, it still has to be easy to use.

“Any soldier can operate [the SBS] with minimal training,” says Cheatham. “They would put it up in the air, let it fly in front of them, and, through its camera being able to video what’s going on underneath it as it moves away from them, it allows the squad to move forward more rapidly than it would if it had to send out a couple of scouts to reconnoitre the area.”

Cheatham has been at the MCoE for just over two decades. Before assuming his present position as its deputy branch chief of electronics and special developments, he was a capabilities development specialist. That experience has provided him with a valuable insight into the degree to which technology may enhance the survivability of the individual infantryman, and the squad as a whole. “Having dealt with various kinds of technologies and things throughout my career, I just wanted to continue even after I retired from the military proper doing what I could do to aid and assist our young warriors on the battlefield,” he tells us.

His main task has been to build on the capabilities of nano-UAVs like the Black Hornet and provide the US Army with a viable system that can be manufactured and deployed en masse.

To that end, Cheatham’s department has acquired several drone platforms, including the PD-100, to inform its progress. Nevertheless, there’s still a problem with demand. While advances continue to be made in the development of individual components – Cheatham cites startling improvements in thermal and high-definition cameras as a primary example – complete examples of complete, off-the-shelf drone models in this area remain thin on the ground. At least, those are actually useful in the combat space.

“In the UK, as well as here in the US, you can go into a hobby store and buy a UAV system for as little as $50,” says Cheatham. “Yet, they really don’t have what is necessary for the militaries to be able to use them in combat. One issue is radio frequencies: you can only use certain ones. That was one of the drawbacks with the Black Hornet, initially, in that it was on the same band as our emergency systems in the US. We even had to get special permissions when we were doing some of the evaluation work and the experimentation work with this to even be able to use it.”

Nevertheless, the race is on to develop a nano-UAV model that can go toe-to-toe, not only with insurgents, but also against militaries using comparable systems. And, increasingly, there’s crossover between the two when it comes to deploying drones.

“You’ve got ISIL or ISIS in Iraq using unmanned aerial systems as flying bombs,” says Cheatham. “They’re a little bit bigger aircraft, have a little bit more lift capability so they can carry a little bit bigger payload. Yet, that’s the way that I see that a lot of the smaller UAVs are being used around the world. Other forces, as you have with our enemy forces currently – the one’s that we’re fighting – don’t have those same restrictions on what they can or cannot use to aid and assist them in wreaking devastation on anything it gets close to.”