Aerion Paving Path To Bring AS2 to Market

 - May 18, 2020, 9:31 AM
Aerion's AS2 is sporting a new look with changes to wing, empennage, and nacelle design as the company lays plans for manufacturing. (Photo: Aerion)

With an eye on bringing a civil supersonic business jet to market around the 2026 timeframe, Aerion Supersonic is laying the groundwork to shift from a design firm to a manufacturer with the selection of Melbourne, Florida, as the site of its new factory and the firming up of a final design of the aircraft. Aerion in late April announced it would break ground later this year on a $300 million facility at Florida’s Melbourne International Airport (MLB) to serve as the home for production of its Mach 1.4, 12-place AS2 trijet.

This announcement came as Aerion firmed up what the company believes is the final design configuration for the airplane, adopting a new look that sports a delta-shaped wing, revamped empennage, and new elongated nacelle shape that Aerion said incorporates new materials and technologies, yet provides a design that could ensure the business jet meets timeline and production requirements.

While the specifications of the changed design are anticipated soon, the company did reveal that the length of the airplane is now shortened to 144 feet, 11 inches, with a 79-foot wingspan and 29-foot height. Aerion executive v-p and chief sustainability officer Gene Holloway likened the configuration to that of the more traditional “coke bottle” shape associated with supersonic aircraft, with a “narrow waist” that flares out in the back.

“The airplane looks remarkably very different from what most people have become accustomed to seeing [with the AS2],” said Holloway, referring to the move away from the more straight-line wing that incorporated supersonic natural laminar flow shapes refined over years of research and the previous T-tail empennage.

“It's not to say that we've abandoned the work we had done going into that original configuration,” he said. “We are still very interested in exploring further the supersonic natural laminar flow technologies. And we continue to look at the development of that.” But at this point Aerion has opted to move in a new direction because, he added, “This is one of those unique periods in history where you begin to have a number of enabling technologies of all kinds of coalesce in their maturity all at the same time.”

As the company looked to optimize the speedy aircraft, engineers refined the choices to enable its vision of cruise performance and level of luxury, while addressing environmental challenges, he said.

“It’s driven us in some respects to go look at some of the other technologies out there that allow us to take advantage of this point in time,” Holloway said. While stressing that “it's not an absolute foregone conclusion that everything is locked up,” he added, “we’re pretty much decided on the configuration going forward” as it “rapidly approaches” the preliminary design review in upcoming months.

While keeping many of the enabling technologies proprietary, Holloway specified that this includes the use of advanced materials and composite structures that previously had not been fully explored on current commercial aircraft. “We're at a point in time where we can begin to leverage a lot of the advanced development work that's [been done] over the last few decades to begin to bring some of those capabilities to bear on developing lighter-weight structures overall.”

He also pointed to advances in avionics systems and ground communications to better manage flights, including prognostic health management. The company has stepped up its selection of suppliers, with GE Aviation providing the Affinity medium-bypass twin-shaft, twin-fan turbofan, Fadec-controlled engines and Honeywell supplying Primus Epic avionics. Several other well-established companies have been tapped to supply aerostructures, wiring, nacelles, landing gear, and the aircraft doors, among other components. These include Spirit AeroSystems, Safran, GKN, Aernnova, and Potez Aeronautique. Boeing remains an integral partner with engineering and other support.

Using traditional suppliers comes in concert with another consideration in incorporating design changes: “There's a timely need to enter the market,” he said, pointing to the target of the middle of the decade. “The world's ready for that. The market's ready for that.”

Along with that is ensuring the producibility of the ultimate design; the design must be efficient, but also “buildable,” he said. “There are clearly things that you can conceive, build models, and aerodynamically look really good. And then as you get further downstream, you start looking at now I've got to go build that.” The design has to work within the materials and manufacturing technologies available.

This is important as the company maps out its production facility in Florida. Aerion will stand up a small team there as it leads up to groundbreaking, with the hope to begin production in 2023 and kick off flight tests in 2024.

“We're all looking anxiously towards the opening of the offices down there,” he said. The massive project, building from a “greenfield position,” provides a number of advantages, he said, particularly as Aerion designs the factory from a sustainability standpoint. “We're committed to being good environmental stewards as we go do this,” he said. “We strongly emphasize that creating a sustainable product, a green, environmentally responsible product, is as important as creating the product to begin with.”

This is a balancing act, requiring a holistic approach to how the company builds a jet and how it is operating, he said, adding this requires “a lot of counterbalancing” and a total-life-cycle approach. And now for Aerion, this approach is “not just in terms of the aircraft itself and its design and operations, but also in terms of the manufacture of the aircraft.”

This means designing a facility with the lowest possible environmental footprint. “We’re going to great lengths as we as we work with our architects to incorporate a lot of the different technologies that are emerging and maturing to a point where they become viable commercially,” he said. This ranges from how the facility is powered, how the walls are designed, and what windows are used to the protections implemented for air quality and even rainwater collection and storage.

Aerion, which is planning a jet that will meet Stage 5 noise requirements and run 100 percent on biofuel, has promoted its approach to sustainability as it faces skepticism from the environmental community and strict environmental requirements that prohibit supersonic flight over land. While deeply involved in international research and deliberations on what may be acceptable in the future, Aerion has taken a practical approach to its design requirements for the AS2, believing that it must be efficient at subsonic, lower supersonic, and higher supersonic speeds.

“We have three design points,” Holloway said, looking at a Mach 0.95 subsonic cruise where the aircraft can reach a range greater than 5,000 nm and a Mach 1.4 supersonic cruise targeting about 4,200 nm. “But then we have a Mach 1.2 design point.” That “boomless cruise” mid-range is aimed at the possibility of one day flying low supersonic speeds over land. Aerion is hoping to prove that, at these lower speeds, there is a “Mach cutoff,” a point where the sonic boom would no longer reach land. Instead, it would dissipate in lower strati of air, depending on a number of conditions. This is where advanced weather technologies can play a role, he said, explaining that the idea is to “just kind of skim the sonic boom off of a layer of the atmosphere.”

These concepts will have to be proved over a period of time, but Holloway said he was encouraged that the FAA notice of proposed rulemaking released last summer to facilitate flight testing is a good first step toward that goal.

As for its supersonic natural laminar flow research, which is one of the hallmarks of Aerion’s engineering expertise, he sees this being incorporated into future projects both commercial and military. He said other projects are in the works at a “high level” of activity.

“It's an exciting time,” Holloway said, reflecting on the number of areas that are starting to come together for the program. “We are a very entrepreneurial group.”