• 18 Jul 2023 10:59 AM
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Forum 79: Civil and Military Air Mobility Innovations

By Frank Colucci
Vertiflite Jul/Aug 2023

Nearly 1,200 people attended the 79th Annual Forum in West Palm Beach, Florida. Some 260 technical papers, 50 invited speakers and 70 exhibitors showcased the “Future of Vertical Flight.”

At the Vertical Flight Society’s 79th Annual Forum & Technology Display, held May 16–18 in West Palm Beach, Florida, incoming VFS Executive Director Angelo Collins reminded his audience, “Future vertical lift — lowercase letters — is really what we are here for.” Forum special sessions reviewed progress towards, and challenges facing, military Future Vertical Lift (FVL) and civil advanced air mobility (AAM) initiatives.

VFS Technical Director Dr. Mahendra Bhagwat — the US Army’s Senior Research Scientist (ST) for Air Vehicle Aerodynamics & Preliminary Design, in the Combat Capabilities Development Command (DEVCOM) Aviation and Mission Center (AvMC) — noted the Forum would hear from authors of more than 260 technical papers and said, “Share their views; question their views. Go ahead, argue. That leads to innovation, and that’s what this Forum is all about.”

Big vertical flight innovators offered Forum attendees industry updates in the annual “Straight Talk from the Top” panel. Tomasz Krysinski, VP of Research & Innovation at Airbus Helicopters, talked about the technologies for clean aviation, with reduced carbon dioxide emissions. Together, more efficient aerodynamics, reduced vehicle mass, improved engines and drivetrains, and hybrid-electric propulsion can cut fuel burn by half and set the stage for low-carbon fuels without higher operating costs. Krysinski observed, “If we can reduce fuel burn by 50%, we can use sustainable aviation fuel. It will be more expensive, but we will need less.” Fully electric and hydrogen-powered aircraft promise even lower emissions. By the Forum, Airbus had logged about 15 flight hours on its new, low-drag DisruptiveLab demonstrator with systems designed for hybrid-electric propulsion. It plans to fly the RACER compound helicopter this November, and will later prove out its Eco-Mode turboshaft-electric propulsion. The all-electric CityAirbus Next Generation should fly next year, and according to Krysinski, “We have something that’s a good compromise between complexity and range.”

As Bell turns its V-280 Valor tiltrotor into the FVL Future Long Range Assault Aircraft (FLRAA) for the US Army, the company continues work on its commercial Nexus hybrid-electric air taxi and all-electric Autonomous Pod Transport (APT) concepts aimed at mass markets. “Vertical Lift aircraft today fly very niche missions, more critical missions,” said Bell Executive Vice President for Engineering Jason Hurst. “These things cannot be done any other way.” The global rotorcraft fleet is nevertheless aging, and according to Hurst, “We’re going through a renovation cycle.” Hurst also highlighted Bell’s studies for the US Air Force and Defense Advanced Research Projects Agency (DARPA) around high-speed vertical takeoff and landing (HSVTOL) aircraft that cruise at up to 400 kt (740 km/h) and hover mid-mission. Hurst said, “We’re looking for new paradigms, changing the configurations and doing the one thing we’ve been told never to do — let the rotor stop.”

By Forum time, the S-102 Raider X compound helicopter was some 97% complete at Sikorsky’s West Palm Beach Development Flight Center. The Future Attack Reconnaissance Aircraft (FARA) contender with coaxial rigid rotors, integrated propulsor and fly-by-wire controls promises the Army higher speeds and greater agility than conventional helicopters. The scalable X2 technologies also hint at new products. Sikorsky Vice President and Chief Engineer Steve Schmidt noted the smaller S-97 Raider continues to fly, and said, “All that data is going into the FARA program.” The Army’s FARA Program Management Office expects competitive prototype demonstration flights in late 2023. If chosen over the Bell Invictus, Sikorsky’s speedy new scout will integrate autonomy demonstrated in an uncrewed Black Hawk last year. Sikorsky has, meanwhile, added hybrid electrification to its pillars of future flight; its HEX hybrid-electric cargo carrier with Matrix autonomy is to fly in 2026 or 2027 (see “The State of the Civil Helicopter Industry: Heli-Expo 2023,” Vertiflite, May/June 2023).

Sikorsky is also teamed with Leonardo and the Italian Ministry of Defense on future helicopter technology for the Italian Army. Leonardo’s insightful Senior VP of Strategy & Innovation Roberto Garavaglia noted all the major rotorcraft manufacturers have similar ideas and said, “The technology enablers we have are really growing the design space for our industry.” He conceded, “Unfortunately, vertical flight remains the most expensive way to move on this planet.”

Garavaglia added, though military customers want optimized designs, they still buy commercial aircraft like the US Air Force AW139/MH-139 and US Navy AW119/TH-73A tailored to military missions. “There is a big debate in the military. It’s mass vs. capability; quantity vs. exquisiteness.... The new technologies are not less expensive. Where is the trade-space, the equilibrium point?” To find the balance, Leonardo markets a broad portfolio including its upcoming dual-use, single-engine AW09 utility helicopter, dedicated AW249 attack helicopter, and fast, long-range AW609 tiltrotor. Garavaglia concluded, “We will need to make some decisions. As engineers, we love to embrace everything which is new. In the end, we are businesses. We only survive, we only thrive, because we can find the right spot in our market. A lot [in] the future will be cooperative, as all of this industry has been so far.”

Leonardo’s cooperation made Boeing the prime contractor for Leonardo’s MH-139 in US Air Force service. Boeing Vertical Lift VP and Chief Engineer Matt Hutchinson said, “The challenge is not really a technical one but a cultural one of matching expectations between a commercial customer and military customer.” With the end of Bell Boeing V-22 production, Boeing’s in-house business centers on proven Chinooks and Apaches upgraded to do more with their increasingly open systems. Hutchinson noted, “Clearly, vertical lift machines can serve very efficiently as data collectors, data distributors and, most importantly, as data nodes on the modern battlefield.” Manned-unmanned teaming with air- and ground-launched effects for example, can extend the reach and improve the survivability of conventional helicopters. Hutchinson also noted that autonomous flight controls envisioned for uncrewed cargo aircraft can pay off in piloted platforms. Hutchinson said, “One of the things it enables the crew to do is to fly the aircraft right to the edge of its envelope.”

At the Edge

The US Army Program Executive Office (PEO) for Aviation breaks its rotorcraft portfolio into today’s “enduring fleet” at the edges of helicopter performance and FVL with transformational speed and range for multi-domain operations around 2030. Enduring Apaches, Black Hawks and Chinooks evolved through models, block upgrades and technology insertions, and FLRAA chief engineer Michelle Gilbert observed, “One of the successes of the Black Hawk was that it was a platform that was able to be upgraded as capabilities were needed for the warfighter. That’s what we’re trying for with FLRAA — not getting everything at once but focusing on a platform that can be upgraded as new capabilities arise. An open systems approach [MOSA] is very important to us.”

The protest over the selection of the V-280 Valor in the FLRAA competition ended in April, and Bell has begun preliminary design of the squad-carrying tiltrotor with MOSA to integrate new capabilities from third-party suppliers rapidly. Gilbert told the Forum audience, “From an acquisition strategy standpoint for FLRAA, we are focused on the first increment to get the speed and range. We are integrating very mature mission systems on that first increment of aircraft.” She added that the PEO is already developing a FLRAA roadmap to integrate improved mission systems and increased autonomy.

PEO Aviation’s Director of MOSA Transformation Matt Sipe reminded the VFS audience that, “The cost of integration is usually just as big of a deal as the cost of development of the new capability.” MOSA aims to cut the cost of both crewed and uncrewed systems. Sean Townsend, Technical Division Chief of the Uncrewed Aircraft Systems (UAS) Project Office helps manage an Army portfolio that ranges from short range, recon quadcopters to the big, fixed-wing Gray Eagle. FVL air launched effects (ALE) are now simply launched effects (LE) that extend the reach of airborne and ground platforms. Townsend explained, “Because they’re engaging before the solider, we have to consider them to be expendable.... The acquisition approach has to be geared towards that.”

Even with FLRAA, FARA and LE, the US Army’s enduring fleet will drive upgrades and technology insertions. The common avionics architecture system (CAAS) was introduced on the Chinook in 2007, and the Block I CH-47F cargo helicopter fleet just standardized on CAAS 9.4. The Block II CH-47F is finishing engineering and manufacturing development and has been ordered by Germany. The AH-64E Apache attack helicopter awaits a new operational flight program to standardize the fleet. More improvements are under consideration. According to Apache product manager Lt. Col. Nick Yerby, “We’re setting the stage for the integration of a new engine and for Army leaders to make decisions on what they want to do with the platform.”

Just what the US Air Force wants to do with its new HH-60W Combat Rescue Helicopter is also to be determined. Focused on the Pacific Command area of operations, the service has reduced its Jolly Green II procurement from 113 new Sikorsky helicopters to just 85. “The Black Hawk is the greatest helicopter that’s ever been produced,” Pave Hawk rescue pilot Col. Charles “Tron” McMullen told the VFS Air Force special session, “I say that because I’m alive because of that aircraft.” McMullen nevertheless offered, “We need something that actually does more than the platform it’s replacing. When we look at the HH-60 Golf moving to the ‘60W, the Air Force took a 160-kt [300-km/h] Black Hawk and made it a 125-kt [230-km/h] platform.... As we start looking at future VTOL platforms... we have to make sure we’re going farther, faster, with all of the capability we know we need to execute the mission.”

HSVTOL for Air Force special operations, medical evacuation and tactical mobility poses new questions. McMullen asked, “With a larger platform, do we need it to hover? Does it need to be high-speed VTOL? Could it be short-takeoff-vertical-landing [STOVL]?”

Rachel Bellanova of the Air Force Research Laboratory (AFRL) Transformational Capabilities Office summarized the HSVTOL market study that sketched a runway-independent aircraft (RIA) with jet-like speed. Sustained hover was a “desirement” rather than a required attribute for an HH-60-sized demonstrator to fly in 2025, and a CV-22-sized platform for 2030. The AFRL analysis concluded in May and identified challenges in propulsion, autonomy and human factors as pilots fly through different flight regimes. “Based on what we saw, we do believe a small VTOL demonstrator is capable in the near-term,” said Bellanova. “Conversely, with the large platform, that is not possible if you have a very high-speed need associated with it. In particular, the propulsion is not there to provide vertical and horizontal flight.”

Less ambitious Air Force missions are candidates for electric VTOL (eVTOL). “We really see electric VTOLs as the third revolution in aerospace,” said Lt. Col. John “Wasp” Tekell, Agility Prime Lead for the AFWERX rapid prototyping effort. “We have new problem sets for distributed logistics, and these new platforms are absolutely part of the solution set we’re considering.” Tekell reported AFWERX had expanded its contract with Joby Aviation and now has four Air Force pilots trained to fly the company’s S4 electric air taxi. Similar plans for the Beta Technologies Alia 250 may begin next year. Agility Prime aims to reduce risk for eVTOL airworthiness certification and understand the manufacturing capability of each of eVTOL prime contractors. “Industry is starting to shift their mindset… from prototype aircraft development to type-conforming aircraft production. The hiring and the mentality is shifting in that direction.”

Research and Develop

Forum special sessions on US and European VTOL research and development spotlighted promising rotorcraft technologies. NASA project manager for Revolutionary Vertical Lift Technology (RVLT) Susan Gorton told the audience that one big focus of the aerospace agency is zero-net carbon emissions by 2050. The most likely route to that ambitious goal is all-electric or hybrid-electric propulsion with 100–200 kW systems eyed for smaller platforms.

NASA has yet to focus on hydrogen propulsion for small cargo vehicles and air taxis, but Gorton said quiet electric AAM aims to make flight “accessible, bringing aviation where it has not been before.” She noted the AAM design space is distinguished by lots of flights in a dense air traffic environment shared with faster vehicles, demanding more automated or autonomous flight control systems (see “Automating the AAM Airspace,” Vertiflite Jul/Aug 2023, for more on this). The urban air mobility (UAM) subspace complicates the challenge. “It requires an airspace that can handle high-density operations. It requires a vehicle that can operate safely and quietly around high-density operations. Once you have a vehicle for a UAM mission, you can expand to things that have longer range, greater payloads or longer endurance.”

NASA researchers have conducted psychometric noise tests to gauge observer reactions to noise. The agency is building a new AAM flight simulator at NASA Armstrong Flight Research Center in California to define the handling and ride quality of AAM vehicles. Gorton said, “We’re counting on people buying more than one ticket, so the ride has to be comfortable for them.” Researchers also dropped a full-scale composite fuselage at Langley Research Center last year to gain insights into AAM crashworthiness and occupant protection (see “Melding Old and New Technology: Impact Testing for Crash Safety,” Vertiflite March/April 2023). “Our test article was completely different from our pre-test predictions,” acknowledged Gordon. “We were stunned.” A second crash test article has been fabricated to drop tentatively next year, and Gorton wants more structural investigations into eVTOL air taxis subject to many flight cycles.

Dr. Oliver Wong, AvMC Associate Director for Design, Simulation and Experimentation, told the Forum audience about US Army work in two science and technology areas covering platforms and mission systems. He said, “A lot of what we’re working on is really far-term technologies.” While FVL is aimed at the Army of 2030, AvMC labs model technologies for 2040. The AvMC concept design assessment branch continues work on computer tools to evaluate new platform configurations. Open systems are central to FVL, and AvMC plans extensive MOSA testing on its fly-by-wire UH-60M and partial-authority EH-60L testbeds. MOSA is also a significant element of the uncrewed launched effects, and AvMC is working on strategies to control swarms of different LE.

The US Naval Air Systems Command (NAVAIR) recently stood up an LE working group to consider Army ideas in manned-unmanned teaming. “I think it’s important to understand that we do talk to each other,” said NAVAIR vertical lift science and technology portfolio manager Mike Fallon. Navy and Marine Corps aviation developments aim to balance quality, performance and cost. He observed, “Usually, you only get two of those.... We’re trying to break that paradigm.”

The NAVAIR Program Executive Office Air Anti-Submarine Warfare, Assault & Special Mission — PEO(A) — now manages the revolutionary V-22 tiltrotor, fly-by-wire CH-53K heavy-lift helicopter, Presidential VH-92 helicopter, multi-sensor MH-60R/S Seahawks, and upgraded AH-1Z and UH-1Y helicopters. It works with NASA, the joint services and industry on sustainment technologies. “When you have unplanned maintenance, that’s when you run into problems,” Fallon said. “Readiness is one of the biggest things for us. Our aircraft are getting older until the next ones come.” The NAVAIR focus on readiness, sustainment and prognostic health monitoring drives work on CBM+: condition-based maintenance, augmented with new sensors, artificial intelligence and digital twins of each aircraft.

To face near-peer threats, the US Naval Aviation Enterprise expects to enhance lethality with the Navy FVL-Maritime Strike and Marine Corps VTOL Family of Systems studies, now including Logistics Connector concepts. NAVAIR’s PEO for Unmanned Aviation and Strike Weapons — PEO(U&W) — is responsible for the MQ-8C Fire Scout UAS, and the PEO for small UAS considers uncrewed logistics concepts. Fallon asked, “Why do we have to spin up a huge H-60 or maybe a UH-1 to deliver a couple of pounds of stuff? Maybe we can do better with a small UAS that’s risk-worthy.”

Pat Collins, rotorcraft technology lead at the UK Ministry of Defense and vice chair of the NATO Next Generation Rotorcraft Capability (NGRC) initiative provided an update on the six-nation effort to begin replacing aging helicopters around 2035. He said, “We haven’t got to the detail side yet, but this is a really good story.” The NGRC vision is a common air vehicle able to carry 12–16 troops more than 900 nm (1667-km) unrefueled (with or without crew) and cruise at 180 kt (333 km/h) entering service, or more than 220 kt (407 km/h) in its objective form.

A modular airframe with open-systems architecture for selected survivability equipment has special appeal to different partner nations. Collins observed, “We know modularity tends to add weight and cost, but the benefits you get from it are insurmountable. It allows a wide range of customers to buy ostensibly the same aircraft.” With a sobering aside, he said, “We started this 10 years ago. Hopefully, we’ll get to first flight in about 12 years.”

European research organizations commonly share resources, and a Forum special session heard from French ONERA and German DLR researchers about collaborations on near- and long-term rotorcraft innovations. ONERA Rotorcraft Program Director Arnaud LePape described some of the unique facilities offered by his agency, including a new distributed electric propulsion and systems integration test rig with eight benches to test motors up to 80 kW, with propellers and representative flight loads. Florian Antrack from DLR described new Crash and Impact Test (CITE) facilities that will be completed by 2027.

ONERA continues long-running work with Airbus on the Racer high-speed compound helicopter demonstrator, and it has parallel efforts on simulation tools for rotorcraft noise and vibration, as well as pilot assistance and autonomy. The Robust Rotorcraft initiative aims to improve reliability, safety, crashworthiness, and icing and lightning protection. Innovative Rotorcraft investigations look at new technologies such as active rotors, high-speed rotorcraft and eVTOL. Collaborative research on deck landings aims to reduce pilot workload and increase safety aboard ship. DLR-developed velocity-hold functions that synchronize the speed of helicopter and ship have helped pilots. ONERA is working on controls to counter heave motion. The work runs through 2025, and Antrack said, “We could have the possibility to support the pilot in [deck] operations much more than nowadays.”

In delivering the 43rd Alexander A. Nikolsky Honorary Lecture, Airbus’s Avionics Executive Expert, Serge Germanetti, considered the “Father of Helionix,” highlighted the evolution of the company’s efforts to reduce pilot workload and enhancing safety by helping pilots manage helicopter performance. He noted that one-third of helicopter accidents are associated with a lack of pilot awareness; technology is a strong enabler for fleet safety, but solutions must be affordable to be widely deployed. Performance management during the flight and awareness of the external environment with new vision-based solutions can open the door to safer operations, he concluded.

Fly and Certify

While the fly-by-wire Bell 525 helicopter and Leonardo AW609 tiltrotor creep through long certification processes, makers of eVTOL aircraft remain confident of quick approval for their radical new flying machines. Forum special sessions covered progress made and challenges ahead.

Dr. Gregor Veble Mikić, head of flight research at Joby Aviation, reviewed the uncrewed flight test accomplishments of his company’s all-electric, six-tilt-prop air taxi and told the audience his company expects the piloted S4 conforming vehicle to be certified in 2025. He said, “I think where we were very successful was using the right tools at the right time to make the fastest progress, whether CFD [computational fluid dynamics] analysis, RCAS [Rotorcraft Comprehensive Analysis System] analysis, whatever is needed to take the project forward.” He continued, “When you start thinking about production and certification, a very different mindset is needed.... You have to embrace different tools for different types of problems. What is important is not to lose that core thinking applied to the right problem.”

Joby engineers conducted fatigue tests of the aeromechanically complex S4 propellers on an ingenious whirl track in Bonny Doon, California. Mikić explained, “We were thinking about building a wind tunnel for this type of test, but the energy costs would have been prohibitive. So, why not take the propeller towards the wind rather than the wind towards the propeller? This has been one of the most instrumental tools that we use to ensure the safety of our vehicle.” A complete propeller system is now undergoing performance and load validation and acoustic tests in the 40-by-80-ft wind tunnel of the National Full-Scale Aerodynamics Complex (NFAC) at NASA Ames Research Center (see “Lost in the Noise,” Vertiflite, May/June 2023).

Joby’s eVTOL effort remains vertically integrated from design to production, with airframe, motors, batteries and avionics made in-house. Meanwhile, Archer Aviation’s production plans call for inventing in-house and integrating from outside suppliers as needed. Lead engineer Dave Dennison noted the Midnight will fly, for example, with home-grown electric motors and carbon fiber propellers supplied by ECS Composites. The battery power system in the 12-motor, winged air taxi uses commercial technology from Molycell in Taiwan. Dennison explained, “We had to make an aircraft that was efficient enough to use a cell that’s highly reliable.”

Archer has orders for 200 Midnight air taxis from United Airlines. A pre-production Midnight should fly this summer and the first of eight conforming test aircraft next year. Two static test articles complete the certification plan, and Archer expects its air taxi to be type certified by late 2024 or early 2025. Time-to-market is essential for a startup with no other revenue. “We’ve got to make it,” acknowledged Dennison. “This is a do-or-die situation.”

Overair Chief Engineer Tony Mumford told the VFS audience about the Butterfly optimum speed tiltrotor (OSTR) and explained the advantages of an eVTOL air taxi with proprotors larger than those of competing designs. “We believe the large rotors will provide an advantage in terms of disk loading,” he said. The four large Butterfly proprotors with individual blade control turn at 400 rpm for quiet takeoff and landing and 200 rpm for efficient cruise, but can step up to 600 rpm for one-prop inoperative operations. The aircraft is also designed to satisfy Category A safety requirements with power margins that afford good hot-and-high performance and speeds up to 170 kt (315 km/h), depending on desired efficiency.

Overair hopes to fly the prototype XP-1A Butterfly this year and an XP-1B soon after to validate computer models and refine the production conforming OA-1 now being designed. Mumford noted the OSTR can be scaled up for larger aircraft. “In the near term, though we’re talking about hybrid and alternate power sources, we’re very focused on battery propulsion at present.” Mumford also observed, “Being a tiltrotor, we could, down the road, introduce a STOL [short takeoff and landing] capability into the way the aircraft will be operated in the future.”

ARC Aerosystems Head of Advanced Technology Glenn Waters described a propulsion-agnostic solution for regional air mobility without expensive new infrastructure. The nine-passenger Linx-P9 uses an unpowered rotor and fixed wing to fly over 500 nm (925 km) with a 2,200 lb (1,000 kg) payload in Part 27 operations. The developer predicts operating costs will be just 70% those of a conventional helicopter. An electric jump motor spins up the rotor for vertical takeoff, and autorotation landings eliminate rollout on touchdown. The company recently bought all the hardware, documentation and intellectual property of the only Part 27-certified autogyro, the 1960s Canadian-designed Avian 2/180 Gyroplane. Waters called it an “ancient roadmap” of how to type-certify an autogyro.

eVTOL developers envision very different concepts of operations for their unconventional and largely automated aircraft. In his Forum presentation, eVTOL flight tester Al Lawless of Aurora Flight Sciences observed, “What’s especially new in this new world is, instead of having a highly-skilled pilot, the whole intent is to drive down the KSA level — the Knowledge, Skills and Ability level — so that we can democratize the piloting task.”

LuftCar founder and CEO Santh Sathya described a hydrogen-powered, multi-purpose, modular Autonomous Air and Road Mobility (AARM) system that carries customized delivery vans to their points of service. A two-seat prototype is expected by the end of 2023.

AIR co-founder and CEO Rani Plaut showed a mockup of his two-seat, all-electric, winged multi-rotor vehicle on the Forum exhibit floor. The AIR ONE personal air vehicle with its simplified flight controls will be certified under FAR Part 91 Experimental Category rules in late 2024 or early 2025 and already has 400 orders, about 60% from buyers without pilot licenses. A prototype is flying in Israel and will be joined this year by two more in the US. Plaut said, “We think the key factor in order to propel the industry is we need customers flying and clocking hours, and we need the number of landings being the same as the number of takeoffs. For this to happen, you need safety measures which correlate with the process you go through with the FAA.”

Mikaël Cardinal, vice president of biotech company United Therapeutics (UT) described networks of crewed and uncrewed eVTOL aircraft systems for organ delivery. He said, “We need to start somewhere and begin making real the use of remotely piloted aircraft as a standard of healthcare for waiting patients.... Typically, between airport and hospital, the last-mile delivery is very challenging when you start talking to surgeons and the medical community.” The company is continuing trials of the EHang electric autonomous octocopter, and is also supporting the development of the bigger, faster Beta Technologies Alia 250 and other electric aircraft for its network. Meanwhile, UT-sponsored Tier 1 Engineering’s e-R44 is also supporting electric motor and battery certification, while Piasecki is developing a hydrogen helicopter (see “Piasecki Relaunches the Heliplex,” Vertiflite Jul/Aug 2023).

Pamir Sevincel of venture capital firm Quartz Capital explained that automation is essential to eVTOL economics and calculated replacing a pilot with a paying passenger can potentially cut the price of the aircraft by 50%. He nevertheless expects autonomous fight controls to be implemented in stages.

Dr. Luuk van Dijk, CEO of autonomy developer Daedalean, told the VFS audience the “flightpath” to autonomy is through optionally piloted vehicles, and said, “We want to build an aircraft that doesn’t kill you if you take your hands off the controls.” The company has integrated a computer vision suite with cameras, processors, and a neural network to interface with cockpit avionics and help pilots find landing zones in visual flight conditions.

Based on the Robinson R44, Rotor Technologies, Inc. markets its autonomous R550X multi-mission helicopter — which can conduct useful operations with an Experimental Category ticket. CEO Dr. Hector Xu reminded the VFS audience, “Computers don’t get tired or lose concentration, and they have access to more data sources.”

He nevertheless drew conclusions from autonomous helicopter disappointments. The Boeing A160 Hummingbird with optimum speed rotor proved building a reliable revolutionary platform for autonomy can be extremely difficult. Boeing’s Unmanned Little Bird did most of its flying with a pilot aboard; Xu said, “Don’t forget to take the pilots out, at least eventually — you miss stuff if you always have a safety pilot aboard.” Kaman’s autonomous K-MAX flew without a pilot in Afghanistan but was limited to simple mission plans with GPS waypoints. The operational testing ended without finding any additional customers. Xu cautioned, “It’s not exactly plug-and-play in aerospace, so be careful of the platform that you pick.”

About the Author

Senior contributing editor Frank Colucci has written for Vertiflite for the past 20+ years on a range of subjects, including rotorcraft design, civil and military operations, testing, advanced materials, and systems integration.