Supersonic & Hypersonic Civilian Transport Projects in Development

by Douglas Messier
Managing Editor

Boom Supersonic’s recent rollout of its XB-1 supersonic demonstrator aircraft marked a milestone in an accelerating race to revive an era of civilian supersonic travel that ended when the Concorde jetliner was retired in 2003.

XB-1, aka Baby Boom, is set to begin flight tests next year from the Mojave Air and Space Port in California. The Mach 2.2 (2,717 km/h, 1,688 mph) vehicle is the precursor to Boom’s 55-seat Overture airliner, which is scheduled to begin carrying passengers in 2029.

Boom’s roll out of the XB-1 came two months after Virgin Galactic unveiled plans for a Mach 3 (3,704 km/h, 2,302 mph) business jet capable of carrying up to 19 passengers.

At least six companies and one government are working on high-speed aircraft that would carry between 9 and 100 passengers at speeds ranging from Mach 1.4 (1,729 km/h, 1,074 mph) to above Mach 5 (6,174 km/h, 3,836 mph). SpaceX plans to use its Starship rocket to zip passengers and cargo between distant locations on Earth at Mach 20.

Supersonic & Hypersonic Vehicle Programs

NASA and Lockheed Martin are developing an experimental aircraft to test low sonic boom technology that will allow supersonic aircraft to fly over land. The Concorde, which flew at Mach 2 (2,470 k/hr, 1,535 mph), was limited to over ocean flights due to the noise the airplane made.

Three companies — Aerion, ExoSonic and Spike Aerospace — say they already possess technology that will allow their supersonic aircraft to fly over land without disturbing people on the ground.

UK-based Reaction Engines is developing the SABRE engine, which would be used to power hypersonic vehicles operating above Mach 5 (6,174 km/h, 3,836 mph). The company recently deepened its cooperation with jet engine maker Rolls-Royce. Reaction Engines also has research agreements with the UK Ministry of Defence and the U.S. Air Force.

Rolls-Royce will supply engines for Boom’s supersonic vehicles. It also signed a non-binding memorandum of understanding (MOU) with Virgin Galactic to work together on supersonic propulsion.

GE Aviation’s Affinity engine will power Aerion’s AS2 business jet. The company has also delivered a F414-GE-100 engine to NASA for the X-59 QueSST program.

High-speed transports have both civilian and military applications. The U.S. government has agreements with three companies — Boom Supersonic, Hermeus and SpaceX — to study the use of their vehicles for quickly transporting personnel and cargo between distant locations.

So, there is a lot going on in the field. Let’s take a closer look at the supersonic and hypersonic vehicles in development.

Boom Supersonic

XB-1 (Baby Boom)
One-third Scale Supersonic Demonstrator
Capacity: 1 pilot
Maximum Speed: Mach 2.2 (2,717 km/h, 1,688 mph)
First Flight: 2021

Overture
Passenger Aircraft
Capacity: 55 passengers
Maximum Speed: Mach 2.2 (2,717 km/h, 1,688 mph)
First Flight: 2025
FAA Certification: 2029

Boom is closer to flight than any of its supersonic aircraft competitors. The Denver-based company rolled out its XB-1 subscale supersonic demonstrator two weeks ago. Flights tests will begin next year in California.

XB-1 is designed to test out the technologies for Overture, a 55-seat passenger plane scheduled to enter commercial service by the end of the decade.

“Boom is currently progressing through the conceptual design phase of Overture, its commercial airliner,” the company said on its website. “The certification program will involve five flight test aircraft with expected rollout in 2025 and completion of type certification in 2029.”

Overture will have an all-business class configuration. The company plans to build larger aircraft that will carrying more passengers and allow airlines to reduce fares.

The company has said future aircraft with low-boom technology will be able to fly over land. Boom said its planes will be carbon neutral by using new renewable fuels.

In 2016, Richard Branson’s Virgin Group placed an order for the first 10 Overture aircraft, which are projected to cost $200 million apiece. The deal included a provision for Virgin Galactic’s subsidiary, The Spaceship Company, to provide manufacturing and testing support for Boom’s supersonic programs.

Japan Airlines has ordered 20 Overture aircraft. Flight Global has reported that three other airlines have raised the total number of Overture orders to 76.

One thing to note is that orders don’t always translate into deliveries. Boeing, for example, has experienced hundreds of order cancellations due to the COVID-19 pandemic and the grounding of the 737 MAX. Airbus has also experienced cancellations.

The Concorde had well over 100 orders from airlines. However, only 20 aircraft were ever built and 12 placed in operation by Air France and British Airways.

Boom has an agreement with the U.S. Air Force to explore how Oveture could be incorporated into the government’s fleet of aircraft.

Funding Raised: $33 million (Series A), $100 million (Series B)
Development Costs: $6 billion (estimated)

Partners: Rolls-Royce (engines), Dassault Systèmes (design & development), Flight Research Inc. (test support), Prometheus Fuels (carbon-neutral fuel), Stratasys (additive manufacturing), JPA Design (interior design)

Aerion

AS2
Business Jet
Capacity: 12 Passengers
Maximum Speed: Mach 1.4 (1,729 km/h, 1,074 mph)
First Flight: 2024
FAA Certification: 2026

Aerion bills its AS2 business jet as the first commercial supersonic aircraft capable of flying over land without the noisy sonic boom that limited the Concorde to flying over the ocean. (ExoSonic and Spike Aerospace are making similar claims.)

In February 2019, Aerion and Boeing announced a partnership to work together on developing the AS2 jet. Boeing is providing financing and engineering, manufacturing and flight-test services.

“Together with Boeing, we’re creating a faster, more connected future with tremendous possibilities for enhancing humanity’s productivity and potential,” said Aerion Chairman, President and CEO Tom Vice.

In April 2020, Aerion announced a deal with the state of Florida to relocated from Reno, Nev. to Melbourne. The company plans to build a global headquarters and integrated campus for the research, design and manufacture of the AS2.

Aerion said it plans a multi-year investment of $300 million in Florida that is expected to generate 675 jobs paying an average of $105,000 each by 2026.

Partners: GE Aviation (engines), Honeywell Aerospace (avionics), Spirit AeroSystems (aerostructures), Safran (landing gear system), GKN Aerospace (empennage, electrical wiring and interconnection systems), Aernnova (aerostructures manufacturing), Potez Aéronautique (aircraft doors)

Spike Aerospace

S-512
Business Jet
Capacity: 12-18 passengers
Maximum Speed: Mach 1.6 (1,976 km/hr, 1,228 mph)
Range: 7,135 miles (11,483 km)

Spike says that the S-512’s patent-pending Quiet Supersonic Flight Technology will allow the business jet to travel at Mach 1.6 over land without creating a loud sonic boom on the ground.

Spike has said the S-512 would cut travel time between major cities by nearly half. For example, a trip from New York’s John F. Kennedy International Airport to London Heathrow would be reduced from 6 hours 12 minutes to 3 hours 18 minutes.

Spike is looking to make its tickets competitive with business class seats on subsonic jets.

The S-512 will feature a windowless Multiplex Digital cabin that will give “the traveler an incredible, panoramic view of the outside world on large full-width digital screens,” the company said.

Partners: Siemens PLM Software, MAYA Simulation (software development, engineering services), Greenpoint Technologies (jet interiors), BRPH (development of manufacturing and test facilities), Quartus Engineering (advanced engineering)

Virgin Galactic

Business Jet
Capacity: 9-19 Passengers
Maximum Speed: Mach 3 (3,704 km/h, 2,302 mph)

Virgin Galactic has conducted a mission concept review on its Mach 3 jet. The review, done with the participation of NASA representatives, “confirmed that, based on the research and analysis work completed, its design concept can meet the high-level requirements and objectives of the mission,” the company said.

The review was conducted under a previously signed Space Act Agreement under which Virgin Galactic and NASA agreed to collaborate on high-speed transportation. 

Virgin Galactic has also signed a non-binding memorandum of understanding with Rolls-Royce to collaborate in the design and development of an engine to power the vehicle.

Following the signing of that agreement, Rolls-Royce announced a deepening of the company’s cooperation with Reaction Engines, which is developing its hypersonic SABRE engine.

Virgin Galactic is also working with the Federal Aviation Administration’s (FAA) Center for Emerging Concepts and Innovation to outline a framework to certify the Mach 3 aircraft to carry passengers.

Boeing invested $20 million in Virgin Galactic after the space tourism company went public last October. The two companies are working together on high-speed transportation.

In 2016, Virgin Galactic announced an agreement to provide manufacturing and testing support for Boom Supersonic’s supersonic development. The support will be provided by Virgin’s subsidiary, The Spaceship Company. The Virgin Group has also placed an order for Boom’s first 10 Overture jetliners.

Virgin Galactic’s supersonic jet project will be overseen by George Whitesides in his new position as the company’s chief space officer. Whitesides stepped stepped down as CEO in July after nearly a decade at the helm. He was replaced by former Disney executive Michael Colglazier.

Hermeus Corporation

Supersonic Jet
Maximum Speed: Above Mach 5 (6,174 km/h, 3,836 mph)
Range: 4,600 miles (7,403 km)

Hermeus is developing a Mach 5 aircraft that would reduce travel time from New York to London from an hours-long ordeal to a mere 90 minutes.

In May 2019, Hermeus announced a seed funding investment led by Khosla Ventures with the participation of unidentified private investors. The amount of the investment was not announced.

Last February, Hermeus successfully tested a Mach 5 engine prototype.

“Using our pre-cooler technology, we’ve taken an off-the-shelf gas turbine engine and operated it at flight speed conditions faster than the famed SR-71. In addition, we’ve pushed the ramjet mode to Mach 4-5 conditions, demonstrating full-range hypersonic air-breathing propulsion capability,” said Hermeus Chief Technology Officer (CTO) Glenn Case in a press release.

In August, the company announced an $1.5 million contract from the U.S. Air Force’s AFWERX to assess modifications to the Mach 5 aircraft to support the Presidential and Executive Airlift fleet.

The Atlanta-based company was founded in 2018 by four veterans of Generation Orbit Launch Services. The founders are Hermes CEO AJ Piplica, Chief Product Officer Michael Smayda, Chief Operating Officer Skyler Shuford, and CTO Glenn Case.

The Hermeus advisory board includes some well known figures in the aerospace industry:

• Rob Meyerson, former president of Blue Origin;
• Bob Weiss, former executive vice president and general manager of Lockheed Martin’s Skunk Works;
• Keith Masback, former CEO of the U.S. Geospatial Intelligence Foundation;
• George Nield, former associate administrator of the FAA’s Office of Commercial Space Transportation;
• Tom Bussing, former vice president of Raytheon Missile Systems; and
• Katerina Barilov, founder of Sparkplug capital+ and managing director of Shearwater Aero Capital.

SpaceX

Starship
Point-to-point Launch Vehicle
Maximum Speed: Mach 20 (24,696 km/h, 15,345 mph)
Range: 10,000 km (6,214 miles)
First Flight: 2020

Want to get to the other side of the world, but you’re fed up with long haul flights on pokey subsonic airliners? Would even the Hermeus Mach 5+ jet be too slow for your needs?

Then strap in to SpaceX’s Starship for the ride of your life. Elon Musk is promising his Starship rocket whisk passengers between distant locations via suborbital flights reaching a speed of Mach 20. All in an hour or less.

There are a few challenges, of course. Starship is a reusable rocket that Musk wants to operate with airline efficiency, frequency and reliability. That achievement would be unprecedented in the long history of rockety.

Starship would need to launch and land at offshore platforms in order to reduce the impact of sonic booms on the uninvolved public. For noise and safety reasons, Starship passenger flights would likely be limited to over ocean routes like the Concorde.

The U.S. Army, however, seems less worried about such restrictions. Earlier this month, the service revealed it is working with SpaceX to study whether Starship can be used to transport equipment and supplies to distant bases. Whereas a C-17 cargo plane might take 12 hours to reach Afghanistan, Starship could transport the same load there in less than an hour.

Starship prototypes are now being tested at SpaceX’s facility at Boca Chica Beach in Texas. Vehicles have made several hops using single Raptor engines. The company preparing a Starship to conduct a higher flight test using three Raptors.

In June 2020, Musk said Starship could be making point-to-point flights within two or three years. He added that SpaceX was planning to build floating spaceports to support hypersonic travel on Earth and trips to orbit, the moon and Mars.

ExoSonic

Passenger Jet
Capacity: 70 passengers
Maximum Speed: Mach 1.8 (2,223 km/h, 1,381 mph)

ExoSonic is building a supersonic aircraft capable of flying over water and land with a muted sonic boom.

The company was recently awarded an U.S. Air Force contract to study how to adapt the jet to meet the needs of the government.

ExoSonic is a fully remote company. It plans to establish an office in the Los Angeles area in the future.

Funding: Y Combinator, AFWERX, U.S. Air Force

NASA — Lockheed Martin

X-59 QueSST
Low-boom Supersonic Demonstrator
Maximum Speed: Mach 1.42 (1,753 km/h, 1,090 mph)
Cruising Altitude: 55,000 ft (16,764 m)

Lockheed Martin’s famed Skunk Works is building the X-59 QueSST (Quiet Supersonic Transport) for NASA. The aircraft is designed to reduce sonic booms so future supersonic vehicles can fly overland routes.

Lockheed Martin plans to deliver X-59 to NASA in late 2021 with flight tests scheduled for the following year over the Mojave Desert. The vehicle will use GE Aviation’s F414-GE-100 engine.

Japan Aerospace Exploration Agency (JAXA)

Conceptual Passenger Jet
Capacity: 100 passengers
Maximum Speed: Mach 5 (6,174 km/h, 3,836 mph)
Cruising Altitude: 25,000 m (82,021 ft)
Range: 9,000 km (5,592 miles)

JAXA is conducting research on a passenger aircraft capable of traveling at Mach 5. The conceptual plan calls for an 90-meter long aircraft capable of carrying 100 passengers across the Pacific Ocean in about two hours.

The aircraft would be powered by four hypersonic turbojet engines that would use convention jet fuel up to Mach 3 and liquid hydrogen up to Mach 5.

The space agency is conducting research into low-boom technologies to reduce the noise the airplane makes.

JAXA is seeking international partners to help cover the estimated 2.4 trillion yen ($22.7 billion) cost of developing the vehicle.