Kaman Corporation is well along in flight testing of its Kargo uncrewed aerial vehicle (UAV) as it progresses toward a fly-off for the U.S. Marine Corps later this year.
The company revealed at Modern Day Marine in Washington, D.C., that its first full-scale Kargo prototype commenced flight testing in December 2023 with support from the Alaska Center for UAS Integration, part of the University of Alaska Fairbanks Geophysical Institute.
The aircraft has since proceeded through most of its hover tests and by mid-April was preparing to move into forward flight tests, according to Romin Dasmalchi, general manager of Kargo UAV.
“Things are going really well,” Dasmalchi told Vertical, while also acknowledging that “it is flight test. So we learn things, we take a break, we make modifications — whether that’s on the software side or on the hardware side, on the aircraft side — and then we get back at it.”
Kaman is working under a contract for the Medium Aerial Resupply Vehicle – Expeditionary Logistics (MARV-EL) program, previously known as Medium Unmanned Logistics Systems – Air (MULS-A). Managed by the Navy and Marine Corps Small Tactical Unmanned Aircraft Systems program office (PMA-263), MARV-EL aims to identify a middle-weight autonomous logistics asset that can provide combat sustainment to Marines when ground or crewed aviation assets are unavailable due to threat, terrain, weather, or competing priorities.
A field user capability assessment for Kargo is currently scheduled for July. It will be evaluated against a competing offering from Leidos.
Kaman first revealed the Kargo concept in September 2021, at which point the company had been testing a half-scale demonstrator for several months. But moving up to a full-scale prototype of the quadcopter drone was no small undertaking.
With flight-ready dimensions of roughly 24 feet (7.3 meters) square from rotor tip to rotor tip, and a gross weight of around 1,500 pounds (680 kilograms), Kargo is clearly closer to a conventional crewed aircraft than a consumer drone. It is being designed to carry a payload of up to 800 pounds (around 360 kilograms), comparable to the external load capability of a Robinson R44 helicopter.
Another distinction between Kargo and most multicopters is that it uses distributed mechanical propulsion, rather than the distributed electrical propulsion (DEP) employed in consumer drones and other electric vertical take-off and landing (eVTOL) aircraft. Instead of sending power to electric motors, Kargo uses a mechanical transmission to transmit power from its Rolls-Royce RR300 turbine engine to the four teetering, two-bladed rotors. This is a chain-driven transmission on the prototype aircraft; the production model will have a lighter and more efficient shaft-driven transmission.
“It’s not that we dislike [DEP] technology — I think that there’s definitely some future there,” Dasmalchi said. But because Kaman wanted to offer a near-term solution for military customers first, he explained, the company ultimately opted for mature technology that could be readily maintained using existing capabilities and infrastructure. “What was necessary for our strategy was speed to market and … the reliability factor that we know our customers need,” he said.
That practical approach is manifested in other ways as well. Kargo’s booms and blades can be folded for shipping in a 20-foot (6.1-meter) intermodal container, along with ground handling wheels, a ground control station, and any other necessary field equipment. Without payload, the aircraft will be able to fly as far as 500 nautical miles (925 kilometers), giving it the ability to self-deploy over long distances.
“The idea here is to solve the logistics problem — don’t burden your customer with additional logistics needs,” Dasmalchi said. “For example, you could probably put these aboard a C-130, but the primary mission of a KC-130 at least for the Marines is to refuel other aircraft. So we don’t want to tie up other logistics assets to perform a logistics mission.”
Meanwhile, Kargo incorporates a “push-button autonomy” package from Near Earth Autonomy that is intended to minimize demands on the user. Kaman has an established relationship with Near Earth, having previously partnered with the Pittsburgh, Pennsylvania-based startup on an autonomy package for the uncrewed K-Max helicopter.
“This is something we want a Marine or soldier to pull out of the box in the field and just tell it what to do, not operate it,” Dasmalchi said. “And then at the receiving end, it’s the same thing: ‘Hey, are you ready to receive payload, yes or no?’ You can imagine if you were in a fighting position and you didn’t want to be compromised, for example . . . then you just tell it to hold, it will go to a predetermined holding location and then come in and drop your payload later.”
Kaman selected the Rolls-Royce RR300 for its demonstrator aircraft because of the model’s efficiency and demonstrated reliability, but Dasmalchi noted that Kaman is open to other engine options as well.
“As we start to refine requirements with our customers, whether that’s on the military or the commercial side, they’re going to have different needs,” he said. “Maybe you want to lift more weight and go shorter distances . . . we can certainly do that. The new transmission design will be capable of taking [a more powerful] engine, so we’re looking into different options there as well.”
While Kaman is focused on bringing Kargo to the military market first, it hopes that commercial customers won’t be far behind. Last year, Kaman announced a long-term partnership with PHI Aviation to develop Kargo for commercial applications, including transporting supplies for offshore oil-and-gas customers. The agreement came with a non-binding order from PHI for 50 Kargo aircraft.
“The amount of revenue per day that an oil rig generates is significant,” said Dasmalchi, noting that offshore customers will sometimes commission a crewed helicopter, “the biggest one they have if they have to, in order to keep that rig operating, and it could be for an O-ring that weighs a few ounces.” Not only could a Kargo UAV transport time-sensitive cargo more efficiently, it could also do so in low-visibility conditions not conducive to crewed flight.
Other potential applications for Kargo include performing inspections of offshore rigs and wind turbines, transporting supplies across austere terrain for mining customers, and delivering humanitarian aid, to name a few. Dasmalchi said that Kaman will be sharing more about its plans for commercial production in due course, but in the meantime is focused on executing on its existing military contracts.
“This is really hard stuff,” Dasmalchi said, noting that for many engineers, the ability to design a clean-sheet aircraft is a once-in-a-lifetime opportunity. “The most important factor is really people . . . and we’ve seen some really incredible superstars work on this program internally to the company. And we’re just super excited about it.”
