Silent Flyer

The Reaper, with its 66-foot wingspan, is a full-blown aircraft and requires a military airbase to operate from, plus a load of support personnel on the ground. It operates very much like traditional aerial reconnaissance. Stalker is more like something from a James Bond movie. It takes off vertically with rotors, then flies like a plane, and requires no infrastructure.

“You could pull a Stalker out of a case on the rooftop of the Embassy in Baghdad, take off vertically, fly the aircraft anywhere in the country undetected at low altitude, gather intelligence for four hours or more, and come back and land on the roof,” says Gardner. “All without leaving the gate.”

Stalker weighs around 50 pounds and can be assembled and flown in ten minutes by a two-person team. Range has always been the big issue with small electric drones, but Stalker is equipped with a fuel cell which combines extended range with stealth.

“We have the first solution that truly solves the range problem,” says Gardner.

The fuel cell can support flight for a record-breaking 39 hours, giving extended range and loiter time, all without the noise of a combustion engine.

Quiet operation is the ace up Stalker’s sleeve. Reapers have to stay high to avoid being heard and keep out of the way of surface-to-air missiles, so they require high-magnification lenses to see anything. Stalker comes in low and unseen, making their sensors far more effective.

“A Stalker with a quality imager operating undetected a couple of hundred meters away can surpass what can be gathered from a Reaper-type at 10,000 feet,” says Gardner.

This applies even more to signals intelligence equipment detecting and hacking signals like Wi-Fi on the ground. Thanks to miniaturization Stalker can carry a variety of sensors including thermal imagers, cameras and electronic gear on one mission. Gardner says 35 sensor payloads, some of them classified, have been flown on the Stalker.

The same miniaturization means that the satellite communications, a large conspicuous bulge on top of the Reaper designed in the 1990s, is replaced by a compact 3-pound Starlink from the 2020s. As with so many electronics, capabilities which used to be big and expensive can now be made small and affordable.

Surviving The Electronic Battlefield

Earlier versions of Stalker have operated since 2006 and U.S. forces have flown them in many conflict zones. Stalkers have been proven in Arctic, desert and jungle conditions. It has been upgraded many times. The latest iteration being acquired by the Marines, known as the Advanced Navigation configuration, builds on lessons from Ukraine. Redwire has delivered more than 200 Penguin drones to Ukraine, and continues to deliver them, in an environment where Russian jamming makes standard GPS useless.

“We work closely with Ukraine to dynamically adapt to changing conditions, and we have been able to leverage that work for the Stalker,” says Gardner.

Because of this constant change, Advanced Navigation is designed as a framework for new technology to be plugged in needed. This may be jam-resistant antennas, new receivers, or entirely new technology like optical navigation which works by identifying landmarks below.

“It’s a fusion engine, a core that allows customers to bring in new technologies and combine them to solve the problem is a way that one single technology cannot solve,” says Gardner.

This futureproofing ensures that Stalker can survive. Other U.S. systems have not fared so well. That includes at least one Reaper in Libya apparently lost due to GPS jamming. Another Reaper crashed on a training mission in 2013 due to a GPS failure without jamming.

Weapons Delivery

Stalker cannot carry the 500-pound bombs or 100-pound laser-guided Hellfire missiles toted by the Reaper. This is not such a disadvantage as you might think.

For one thing, Stalker carries a laser designator. It can use its up-close reconnaissance capability to find and designate targets for other aircraft like stealthy F-35s. Teamwork removes the need for the reconnaissance platform itself to be armed,

But Stalker can carry miniature weapons of its own, using precision rather than heft.

“Stalker easily integrates a wide variety of payloads, including droppable munitions,” says Josh Stinson, CGO of Redwire’s Defense Tech business. The U.S. Army has tested a variety of weapons from Stalkers including modified 81mm mortar bombs and custom-made munitions. And they are effective.

“Instead of a Hellfire missile costing $100,000 to $150,000 per round, this solution costs about $800,” Major Rachel Martin, director of the Unmanned Advanced Lethality Course told Defense Post.

Experience in Ukraine shown that small drones with precision weapons can destroy most targets. In Iran, Reapers have been hunting mobile missile launchers. A missile is a thin-walled metal cylinder filled with rocket fuel and explosive, it does not take much to destroy one and a small bomb will be more than enough.

And when something with more range and precision, Stalker can carry attack FPVs, a practice now widespread with similar drones in Ukraine.

“Stalker can also act as a mothership so we can get these super small FPVs to operate at range.,” says Stinson. “The Stalker acts as a relay so the FPV operator can control the FPV in the normal way, they’re just a hundred kilometers from the target. We have demonstrated that, and there may be some customers who have that capability.”

It is worth noting that the Pentagon recently acquired small drones with the ability to fly inside buildings to carry out attacks, plus the technology to operate them from motherships. Teamed with the Stalker’s stealth and surveillance capabilities they would make a formidable combination for long-range precision strike against all sorts of targets.

Safety In Numbers

Mainly though, Stalkers can be deployed at scale. Part of the problem with Reapers is the sheer number of people needed to operate them, including ground crew, a take-off crew at the launch site, plus maintenance and support, all in addition to the remote pilots in Nevada. This leads to jokes about how many people are needed for “unmanned” aircraft operations.

“It takes over 150 personnel or Airmen to maintain a single MQ-9 [Reaper] orbit. That doesn’t seem too unmanned to me.” Air Force Lt. General Tony Bauernfeind told reporters in 2023.

Lack of available manpower was serious issue for getting enough Reapers into Iraq. Stalker can be operated by a team of two.

There is also the question of affordability. While Reaper has become steadily more expensive-– allies can expect to pay around $100m for the latest export version with all the extras--the smaller drone is much, much more affordable.

“Stalker is whole orders of magnitude less expensive than big drones,” says Stinson.

While no exact dollar figure is available, a look at export deals suggests that the Stalker is literally around 100 times more affordable than the latest Reaper variant. That means more Stalkers can be thrown in to flood the zone. It also means that if a few are lost, it is no big deal and gaps can be plugged easily.

The Reaper was never designed to operate in a contest environment where it might have to face air defenses. A medium-altitude, comparatively slow, non-stealthy aircraft, it is an easy target for surface-to-air missiles. In Ukraine, the Bayraktar TB2, the nearest equivalent to the Reaper, had a brief spell of glory which was ended by intensified Russian air defenses. Now the Bayraktar is very much out of the spotlight and reconnaissance is carried out by small, highly capable drones like the Penguin which are more survivable.

Unlike Reaper, Stalker can operate below the radar. And even if it is spotted it can disappear again.

“In flight, Stalker operates effectively within radar clutter and can exploit Doppler notch conditions, complicating tracking by conventional air defense systems,” says Stinson.

In Doppler notching the low-flying drone tuns and flies at right angles to the radar beam, causing it to disappear into ground clutter. Such tactics means that not only can Stalkers gather intelligence from places where a Reaper could not survive, adversaries may not even know they were there.

Stalker is currently cast in a niche role as a useful asset for Special Forces and others. But it could be acquired in larger numbers and do much more. There is no current push to phase out Reapers, though if the conflict in Iran resumes, they may phase themselves out. When planners are looking for something to fill the role in future, they might want to think about something which looks more like a fleet of Stalkers than a handful of Reapers.