Robotic aircraft will accompany human-piloted planes, adding firepower and thwarting enemy attacks
If you drive along the main northern road through South Australia with a good set of binoculars, you may soon be able to catch a glimpse of a strange, windowless jet, one that is about to embark on its maiden flight. It's a prototype of the next big thing in aerial combat: a self-piloted warplane designed to work together with human-piloted aircraft.
The Royal Australian Air Force (RAAF) and Boeing Australia are building this fighterlike plane for possible operational use in the mid-2020s. Trials are set to start this year, and although the RAAF won't confirm the exact location, the quiet electromagnetic environment, size, and remoteness of the Woomera Prohibited Area make it a likely candidate. Named for ancient Aboriginal spear throwers, Woomera spans an area bigger than North Korea, making it the largest weapons-testing range on the planet.
The autonomous plane, formally called the Airpower Teaming System but often known as “Loyal Wingman," is 11 meters (38 feet) long and clean cut, with sharp angles offset by soft curves. The look is quietly aggressive.
Three prototypes will be built under a project first revealed by Boeing and the RAAF in February 2019. Those prototypes are not meant to meet predetermined specifications but rather to help aviators and engineers work out the future of air combat. This may be the first experiment to truly portend the end of the era of crewed warplanes.
“We want to explore the viability of an autonomous system and understand the challenges we'll face," says RAAF Air Commodore Darren Goldie.
Australia has chipped in US $27 million (AU $40 million), but the bulk of the cost is borne by Boeing, and the company will retain ownership of the three prototypes. Boeing says the project is the largest investment in uncrewed aircraft it's ever made outside the United States, although a spokesperson would not give an exact figure.
The RAAF already operates a variety of advanced aircraft, such as Lockheed Martin F-35 jets, but these $100 million fighters are increasingly seen as too expensive to send into contested airspace. You don't swat a fly with a gold mallet. The strategic purpose of the Wingman project is to explore whether comparatively cheap and expendable autonomous fighters could bulk up Australia's air power. Sheer strength in numbers may prove handy in deterring other regional players, notably China, which are expanding their own fleets.
“Quantity has a quality of its own," Goldie says.
The goal of the project is to put cost before capability, creating enough “combat mass" to overload enemy calculations. During operations, Loyal Wingman aircraft will act as extensions of the piloted aircraft they accompany. They could collect intelligence, jam enemy electronic systems, and possibly drop bombs or shoot down other planes.
“They could have a number of uses," Goldie says. “An example might be a manned aircraft giving it a command to go out in advance to trigger enemy air defense systems—similar to that achieved by [U.S.-military] Miniature Air-Launched Decoys."
The aircraft are also designed to operate as a swarm. Many of these autonomous fighters with cheap individual sensors, for example, could fly in a “distributed antenna" geometry, collectively creating a greater electromagnetic aperture than you could get with a single expensive sensor. Such a distributed antenna could also help the system resist jamming.
“This is a really big concept, because you're giving the pilots in manned aircraft a bigger picture," Boeing Australia director Shane Arnott says. These guidelines have created two opposing goals: On one hand, the Wingman must be stealthy, fast, and maneuverable, and with some level of autonomy. On the other, it must be cheap enough to be expendable.
The development of Wingman began with numerical simulations, as Boeing Australia and the RAAF applied computational fluid dynamics to calculate the aerodynamic properties of the plane. Physical prototypes were then built for testing in wind tunnels, designing electrical wiring, and the other stages of systems engineering. Measurements from sensors attached to a prototype were used to create and refine a “digital twin," which Arnott describes as one of the most comprehensive Boeing has ever made. “That will become important as we upgrade the system, integrate new sensors, and come up with different approaches to help us with the certification phase," Arnott says.
The physical result is a clean-sheet design with a custom exterior and a lot of off-the-shelf components inside. The composite exterior is designed to reflect radar as weakly as possible. Sharply angled surfaces, called chines, run from the nose to the air intakes on either side of the lower fuselage; chines then run further back from those intakes to the wings and to twin tail fins, which are slightly canted from the vertical.
This design avoids angles that might reflect radar signals straight back to the source, like a ball bouncing off the inside corner of a box. Instead, the design deflects them erratically. Payloads are hidden in the belly. Of course, if the goal is to trigger enemy air defense systems, such a plane could easily turn nonstealthy.
The design benefits from the absence of a pilot. There is no cockpit to break the line, nor a human who must be protected from the brain-draining forces of acceleration.
“The ability to remove the human means you're fundamentally allowing a change in the design of the aircraft, particularly the pronounced forward part of the fuselage," Goldie says. “Lowering the profile can lower the radar cross section and allow a widened flight envelope."
The trade-off is cost. To keep it down, the Wingman uses what Boeing calls a “very light commercial jet engine" to achieve a range of about 3,700 km (2,300 miles), roughly the distance between Seville and Moscow. The internal sensors are derived from those miniaturized for commercial applications.
Additional savings have come from Boeing's prior investments in automating its supply chains. The composite exterior is made using robotic manufacturing techniques first developed for commercial planes at Boeing's aerostructures fabrication site in Melbourne, the company's largest factory outside the United States.
The approach has yielded an aircraft that is cheaper, faster, and more agile than today's drones. The most significant difference, however, is that the Wingman can make its own decisions. “Unmanned aircraft that are flown from the ground are just manned from a different part of the system. This is a different concept," Goldie says. “There's nobody physically telling the system to iteratively go up, left, right, or down. The aircraft could be told to fly to a position and do a particular role. Inherent in its design is an ability to achieve that reliably."
Setting the exact parameters of the Loyal Wingman's autonomy—which decisions will be made by the machine and which by a human—is the main challenge. If too much money is invested in perfecting the software, the Wingman could become too expensive; too little, however, may leave it incapable of carrying out the required operations.
The software itself has been developed using the digital twin, a simulation that has been digitally “flown" thousands of times. Boeing is also using 15 test-bed aircraft to “refine autonomous control algorithms, data fusion, object-detection systems, and collision-avoidance behaviors," the company says on its website. These include five higher-performance test jets.
“We understand radar cross sections and g-force stress on an aircraft. We need to know more about the characteristics of the autonomy that underpins that, what it can achieve and how reliable it can be," Goldie says.
“Say you have an autonomous aircraft flying in a fighter formation, and it suddenly starts jamming frequencies the other aircraft are using or [are] reliant upon," he continues. “We can design the aircraft to not do those things, but how do we do that and keep costs down? That's a challenge."
Arnott also emphasizes the exploratory nature of the Loyal Wingman program. “Just as we've figured out what is 'good enough' for the airframe, we're figuring out what level of autonomy is also 'good enough,' " Arnott says. “That's a big part of what this program is doing."
The need to balance capability and cost also affects how the designers can protect the aircraft against enemy countermeasures. The Wingman's stealth and maneuverability will make it harder to hit with antiaircraft missiles that rely on impact to destroy their targets, so the most plausible countermeasures are cybertechniques that hack the aircraft's communications, perhaps to tell it to fly home, or electromagnetic methods that fry the airplane's internal electronics.
Stealth protection can go only so far. And investing heavily in each aircraft's defenses would raise costs. “How much do you build in resilience, or just accept this aircraft is not meant to be survivable?" Goldie says.
This year's test flights should help engineers weigh trade-offs between resilience and cost. Those flights will also answer specific questions: Can the Wingman run low on fuel and decide to come home? Or can it decide to sacrifice itself to save a human pilot? And at the heart of it all is the fundamental question facing militaries the world over: Should air power be cheap and expendable or costly and capable?
Other countries have taken different approaches. The United Kingdom's Royal Air Force has selected Boeing and several other contractors to produce design ideas for the Lightweight Affordable Novel Combat Aircraft program, with test flights planned in 2022. Boeing has also expressed interest in the U.S. Air Force's similar Skyborg program, which uses the XQ-58 Valkyrie, a fighterlike drone made by Kratos, of San Diego.
China is also in the game. It has displayed the GJ-11 unmanned stealth combat aircraft and the GJ-2 reconnaissance and strike aircraft; the level of autonomy in these aircraft is not clear. China has also developed the LJ-1, a drone akin to the Loyal Wingman, which may also function as a cruise missile.
Military aerospace projects often have specific requirements that contractors must fulfill. The Loyal Wingman is instead trying to decide what the requirements themselves should be. “We are creating a market," Arnott says.
The Australian project, in other words, is agnostic as to what role autonomous aircraft should play. It could result in an aircraft that is cheaper than the weapons that will shoot it down, meaning each lost Wingman is actually a net win. It could also result in an aircraft that can almost match a crewed fighter jet's capabilities at half the cost.
This article appears in the January 2020 print issue as “A Robot Is My Wingman."