Aerion Unveils AS3 Mach 4-Plus Airliner Concept

The first image of Aerion's AS3 concept.
Credit: Aerion Supersonic

Supersonic business jet developer Aerion has released the first image of a planned follow-on airliner concept designed for entry-into-service around the end of the decade which will cruise at higher Mach cruise numbers closer to the hypersonic region.

Building on the design, structures and aerodynamic technologies developed for Aerion’s AS2 Mach 1.4 aircraft currently in final design, the larger airliner concept will cruise at more than twice the speed and be capable of trans-Pacific ranges. Although details are being kept deliberately obscure, the 50-seat Aerion concept appears to be a sharply swept delta configuration incorporating twin vertical tails and four engines clustered in two underwing pods.

Despite Aerion’s focus for the past decade on development of the AS2, now scheduled to enter initial production in 2023, the Nevada-based company revealed in 2020 that it was pursuing a longer-term plan to grow a broader family of faster, larger aircraft. In February 2021, as a prelude to the AS3 reveal, Aerion announced it was expanding on-going study work with NASA “with the intention of accelerating the realization of commercial high-speed flight and faster point-to-point travel, specifically studying commercial flight in the Mach 3-5 range.”

Aerion says that concept design work on the AS3 is underway and includes “input from potential customers.” It adds the design will “incorporate revolutionary advances in technology to improve efficiency and reduce the environmental impact of supersonic flight,” and says the aircraft will have a range of 7,000 nm.

The associated work with NASA, conducted under a Space Act agreement, builds on two previous collaborative study contracts and focuses on propulsion and thermal management technologies. Awarded as part of NASA’s Hypersonic Technology Project (HTP) the Aerion contract also specifically includes the evaluation of integrated power generation and cabin systems.

The company is using its in-house-developed aerodynamic optimization tools as part of the study. The tools will be used to “conduct technology assessments on future concepts and aid a transition to the faster aircraft of tomorrow,” according to Aerion.

Although few specific details beyond the planned passenger capacity and range have been revealed, Aerion CEO Tom Vice said the AS3’s sub-hypersonic target speed forms part of a step-wise strategic approach to affordably develop technology for future high-speed generations. Speaking to Aviation Week in May 2020 he said: “We’ve been thinking about hypersonics a little differently. There is an interesting sweet spot around Mach 4.5. It still gets you from the U.S. to Japan in two hours or less but without some of the problems in terms of material science and high tech, non-ablative systems and active cooling structures.”

Guy Norris

Guy is a Senior Editor for Aviation Week, based in Colorado Springs. Before joining Aviation Week in 2007, Guy was with Flight International, first as technical editor based in the U.K. and most recently as U.S. West Coast editor. Before joining Flight, he was London correspondent for Interavia, part of Jane's Information Group.


Operating at that Mach is a thermal and materials issue more than anything else. M*L/D just gets better in this speed range. The propulsion tech is understood. A Bomac missile accidentally exceeded Mach 4 and continued to accelerate before the aluminum structure overheated and disintegrated during test due to a stuck fuel control valve.
One might also note that the speed of sound in sea water is about 4.4. Exceeding this speed the shock wave from air will transfer to the ocean and propagate in the water.
One should ask, just when will Aerion produce a vehicle that flies? I have been reading about Aerion seemingly forever. They may do other things but airplanes? When?
"Building on the design, structures and aerodynamic technologies developed for Aerion’s AS2 Mach 1.4 aircraft currently in final design, the larger airliner concept will cruise at" (M4.5)
I find the idea that 1.4 says anything useful about 4.5 hard to understand. When Johnson was talking about the M3.2-3.3 A-12 he said something to the effect that everything had to be new. And he was presumably comparing to the M2-2.4 F-104, though maybe not quite the M4.3 X-7.
Speed of sound in water about 1.5 km/sec (about 3400 mph). Ref to 4.4 totally obscure and speed of shock wave when it hits water is not the speed of the aeroplane (at, say, 90,000 feet).
If only a Mach 4 passenger airplane was operationally practical, let alone certifiable. This is daydreaming triggered by funding opportunities.