Uncrewed aircraft developer Phenix Solutions has unveiled a full-sized prototype of its remotely piloted heavy-lift rotorcraft at the Heli-Expo show in Anaheim.
Following its appearance at the show, the airworthy example of Phenix’s Ultra 2XL will be used for a flight-test campaign at the start-up’s headquarters in McMinnville, Oregon through a partnership with the University of Alaska and under the supervision of the US Air Force’s Agility Prime programme.
“We’re entering a two-month deliberate flight-test regime that we’re executing right now,” president and co-founder Brian Riese said on 26 February. “That programme is going to culminate with some directed flight tests for our [Department of Defense] customers.”
Phenix launched in 2019, became part of the original Agility Prime programme cohort the following year, alongside leading electric vertical take-off and landing (eVTOL) start-ups such as Joby Aviation and Beta Technologies.
Riese says Phenix is going after relatively “low-hanging fruit” by focusing on cargo operations rather than the air taxi mission. It has worked to develop something of a Swiss Army knife with the Ultra 2XL, which burns jet fuel and is powered by a Rolls-Royce M300 turbine engine.
The aircraft is designed to be adaptable for fire-fighting, search and rescue, agricultural and utility operations – basically, anything that could be considered ”dirty, dull and dangerous” work for human pilots, Riese says.
For example, Phenix says that its technology delivers “targeted spray” applications for crops “while minimising drift and other impacts”, and can also be applied for reforestation efforts with “precision fertilisation”. For defence purpose, Phenix also sees potential to assist with logistics in contested environments.
Flying cargo will be the aircraft’s bread-and-butter use case, thanks to a payload of 680kg (1,500lb). And it is designed with durability and ease of maintenance in mind.
“This aircraft is extraordinarily simple,” Riese says. “It’s all-aluminium; it’s bolted together. You’re using simple materials with known material qualities and certification data, which is very helpful not for the FAA, but also for military certification authorities.”
The Ultra 2XL noticeably features a pair of double-stacked coaxial rotors. The differential torque provided by the counter-rotating system eliminates the need for a tail rotor, Riese says.
“The predominance of your aircraft incidents and mishaps are tail strikes,” Riese says. “We’ve eliminated that.”
Additionally, the Ultra 2XL features a large internal fuel tank and capacity for external tanks, allowing for fuel and payload trade-offs “that are really customisable to a specific customer and use”.
“For example, if you’ve got a defence customer that needs an ISR – intelligence, surveillance and reconnaissance – type of mission, those external fuel tanks would really give quite long endurance to the aircraft,” he says. “If you’re into that lifting heavy payload piece – like a fire-attack mission or the military cargo piece – this is a great tool for that mission, too. We can trade that fuel for payload.”
Currently, the aircraft is operated with a pilot on the ground “always in the loop”, Riese says. In the future, Phenix intends to embrace increasingly autonomous flight systems.
“Certainly, as we look at that continuum of automation, it gets more refined and more capable to take on more tasks,” he says. “And we have some of those feature sets that we’ve prototyped and developed.”
For now, the company is focused on the “10-metre target of getting through our flight trials, satisfying the programmes we have with our partners and moving into production”, Riese says. Phenix is pursuing a Part 27 rotorcraft certification with the Federal Aviation Administration but does not specify when the Ultra 2XL is anticipated to enter commercial service.
