The world got its first taste of commercial supersonic flight over 40 years ago with the Anglo-French Concorde and Soviet Tupolev Tu-144. These sleek, futuristic airliners could whisk passengers across the Atlantic in under 3.5 hours, crossing the ocean at over twice the speed of sound. It was a mind-bending display of raw power and engineering prowess, but ultimately proved to be a commercial failure.
Tremendous fuel consumption made operating costs prohibitively expensive. Sonic booms restricted flights to over-water routes only. And a tragic Concorde crash in 2000, combined with a downturn in air travel after 9/11, sealed their fate. The last Concorde flight touched down in 2003, grounding supersonic passenger travel indefinitely.
Now, a new wave of innovators is on the verge of not only resurrecting faster-than-sound passenger flight but pushing it to new heights. Leveraging advanced computer modeling, 3D printing, next-gen materials, and hard-won lessons from the past, they aim to do what the Concorde could not – make supersonic flight efficient, affordable, and accessible enough for the mainstream.
The Contenders
Boom Supersonic Overture
Leading the charge is Colorado-based startup Boom Supersonic, which has pre-orders from United Airlines and Japan Airlines for its Overture airliner. The 65-88 seat aircraft is designed to fly at Mach 1.7 (1,300 mph) with a range of 4,250 nmi, allowing it to serve hundreds of transoceanic routes in half the time of current jets.
While similar in appearance to the Concorde, the Overture incorporates decades of advances in aerodynamics, materials, and propulsion to boost performance:
- Carbon fiber composites to reduce weight and drag
- Gull wings and area ruling to optimize supersonic airflow
- More efficient, lightweight, and durable turbofan engines
- Noise-reducing engine placement and nozzle design
- Capability to run on 100% sustainable aviation fuel
Boom founder and CEO Blake Scholl believes these improvements, aided by the inexorable progress of technology, will enable ticket prices comparable to subsonic business class – around $5,000 round trip for a NYC to London flight. If achieved, it could open supersonic travel to a much wider market than the Concorde ever enjoyed.
Boom plans to roll out the first full-scale Overture jet in 2025, fly it in 2026, and launch commercial service by 2029.
| Spec | Value |
|---|---|
| Top Speed | Mach 1.7 (1,300 mph / 2,090 km/h) |
| Cruise Altitude | 60,000 ft (18,300 m) |
| Range | 4,250 nmi (4,888 mi / 7,867 km) |
| Passengers | 65-88 |
| Length | 205 ft (62 m) |
| Wingspan | 94 ft (29 m) |
| Engines | 4x medium-bypass turbofans |
| Price | $200 million |
| EIS Target | 2029 |
Aerion AS2
Aerion Supersonic is targeting the business jet market with its 8-12 passenger AS2. Powered by GE Affinity supersonic engines, the $120 million jet is designed to reach Mach 1.4 with a range of 5,466 miles.
Aerion‘s "boomless cruise" technology enables the AS2 to fly without a sonic boom at speeds up to Mach 1.2 over land and sea. This would allow it to operate efficiently on hundreds of global city pairs without the need for speed restrictions or noise waivers.
The company has secured a $2.4 billion order from fractional jet provider Flexjet and is collaborating with Boeing and Spirit AeroSystems to get the AS2 off the ground. First flight is planned for 2024, with entry into service in 2026.
| Spec | Value |
|---|---|
| Top Speed | Mach 1.4 (1,074 mph / 1,728 km/h) |
| Cruise Altitude | 57,000 ft (17,400 m) |
| Range | 5,466 mi (8,797 km) |
| Passengers | 8-12 |
| Engines | 3x GE Affinity medium-bypass turbofans |
| Price | $120 million |
| EIS Target | 2026 |
Spike Aerospace S-512
Boston‘s Spike Aerospace has a unique take with its 12-18 passenger S-512 supersonic business jet. In place of window rows, the aircraft will feature a wraparound array of screens displaying panoramic views from exterior cameras, with the option to watch entertainment or conduct video conferences.
The S-512‘s slender fuselage and cranked delta wing are optimized to cruise efficiently at Mach 1.6 without a sonic boom. Spike says the jet will fly overland routes without disturbing people on the ground, allowing market access impossible for the Concorde.
The S-512 project is still securing funding but aims to have a flying prototype by 2023 and customer deliveries by 2028.
| Spec | Value |
|---|---|
| Top Speed | Mach 1.6 (1,218 mph / 1,960 km/h) |
| Cruise Altitude | 50,000 ft (15,200 m) |
| Range | 6,200 mi (9,977 km) |
| Passengers | 12-18 |
| Engines | 2x turbofans (TBD) |
| Price | $100 million (est.) |
| EIS Target | 2028 |
NASA X-59 QueSST
NASA and Lockheed Martin are taking a more research-driven approach with the X-59 Quiet Supersonic Technology (QueSST) demonstrator. The project aims to prove it‘s possible to fly over land at supersonic speeds without causing a troublesome sonic boom.
The X-59‘s long, pointy 30-foot nose, swept delta wings, and engine placement all aim to control shock waves and prevent them from coalescing into a loud boom. Other speed plane features include:
- Lightweight composite structures and high-efficiency GE F414 turbofan
- External vision system replacing forward-facing windows
- Advanced digital flight controls and boom-sensing instrumentation
When it flies in 2023, the X-59 will cruise at Mach 1.42 at 55,000 feet over U.S. communities, generating no more than a 75 decibel "sonic thump" – about as loud as a car door closing. NASA will gather data on public acceptance of the low-boom flights to inform an eventual overhaul of FAA and ICAO supersonic flight rules.
If successful, the X-59 could be the key to unlocking the economic case for supersonic passenger travel by enabling overland routes between large inland city pairs. A NASA sonic boom study found that permitting overland flights would more than double the potential supersonic air travel market.
| Spec | Value |
|---|---|
| Top Speed | Mach 1.42 (925 mph / 1,488 km/h) |
| Cruise Altitude | 55,000 ft (16,800 m) |
| Length | 97.5 ft (29.7 m) |
| Wingspan | 29.5 ft (9.0 m) |
| Engines | 1x GE F414-GE-100 turbofan |
| Max Takeoff Weight | 32,300 lb (14,600 kg) |
| Program Cost | $520 million (NASA contract value) |
| First Flight Target | 2023 |
The Digital Technology Edge
What sets this new generation of supersonic contenders apart from past attempts is not just advances in aerospace engineering but also the revolutionary capabilities digital technologies provide.
Boom has made digital innovation core to its approach, harnessing simulation tools to optimize aircraft designs for supersonic speed and efficiency without costly physical iterations. The company‘s engineers rely on cloud-based 3D design and virtual prototyping to accelerate development and streamline collaboration with global partners.
AI and machine learning are increasingly integral to modeling the complex aerodynamics at play in supersonic flight. By training self-learning algorithms on massive amounts of wind tunnel and real-world flight data, engineers can rapidly explore and refine designs.
NASA is relying heavily on advanced CFD (computational fluid dynamics) codes to model the shockwave behavior around the X-59 airframe and devise techniques to reduce sonic booms. Highly detailed simulations allow scientists to visualize shock propagation patterns and virtually "test" different boom mitigation ideas at a fraction of the cost of physical trials.
Digital twin technology – virtual 3D models twinned to physical products – is also changing the game. Boom, Aerion, and Spike are all using digital twins to mirror every aspect of their supersonic planes, from design and production to real-time monitoring of flights and predictive maintenance. Fed with live data from sensors, digital twins can help engineers optimize performance, predict failures, and make smarter decisions.
Additive manufacturing, aka 3D printing, is drastically compressing development cycles. Boom has partnered with VELO3D to 3D print complex flight hardware for its XB-1 demonstrator aircraft. The ability to rapidly turn digital designs into testable parts speeds learning and cuts costs compared to traditional fabrication methods.
Challenges Ahead
While the digital age has accelerated supersonic development, major challenges remain before travelers can hop on a Mach 2 jet.
Foremost is cracking the boom problem. The FAA‘s long-standing ban on civil supersonic flight over U.S. soil, and similar restrictions in Europe, severely limit the routes speedier jets can serve. New low-boom designs like the X-59 still need to prove they can fly over populated areas without undue noise disturbance.
Fuel efficiency and environmental impact are also key concerns. Although all the major supersonic contenders plan to use sustainable aviation fuels, the fact remains that pushing through the sound barrier burns 7-9 times more fuel per passenger than subsonic travel. In an era of flight shaming and "Greta Thunberg effect," some question whether a return to faster-than-sound flight is environmentally or ethically justifiable.
On the regulatory front, policymakers are only beginning to update rules to accommodate supersonic flight. In 2020, the FAA proposed noise certification standards for supersonic aircraft, but the rulemaking process will likely stretch well into this decade. The ICAO‘s Committee on Aviation Environmental Protection (CAEP) is also working to set new global sonic boom limits and CO2 emission standards.
Aircraft certification and airworthiness standards for supersonic transports have a long way to go to catch up with subsonic commercial jets. Building confidence in the reliability and safety of radically new designs operating under extreme conditions is no simple task.
Finally, there‘s the business case. Boom, Aerion, and Spike are banking on technology improvements and boom-mitigating designs to get costs low enough to stimulate significant demand. But some analysts remain skeptical, noting the niche nature of the market for ultra-fast travel.
"Supersonic economics have always been very challenging and will continue to be challenging," said George Hamlin, an aerospace analyst and former airline executive. "The Concorde had relatively few seats and they were never able to fill them, even with the deep pockets of British Airways and Air France."
Outlook
Despite the headwinds, the companies at the forefront of the supersonic revival are all-in on their vision of a faster future.
"We see a future where you‘ll be able to get anywhere in the world in four hours for a hundred bucks," said Scholl. "To get there you have to improve fuel efficiency, but you also have to make the aircraft cheaper and more efficient to operate. So that‘s what we‘ve gone to work on."
Boom projects a $300 billion 10-year market for 1,000 supersonic airliners if it can achieve its targeted price point of $5,000 for a round-trip transatlantic flight. Aerion sees demand for 300 AS2 business jets over 10 years and 500 over 20 years as flights save a day‘s worth of travel time for globe-trotting executives.
Spike believes digital tech advances will be the key to making supersonic flight economically sustainable this go-around. "We firmly believe that the advancement of enabling technologies like composites, aerodynamics, and simulation software have converged today to make a commercially viable supersonic passenger jet possible," said CEO Vik Kachoria.
While a Concorde-style "big bang" debut of mass supersonic service may be unlikely, 2021 seems poised to kick off a decade of tangible progress. With players big and small pushing the bounds of aerospace innovation and digital technology harder than ever, we may finally see economically viable faster-than-sound travel take flight.
