Research & Development
JAXA promotes three research and development programs and a fundamental research program that underpins them.
Supersonic transport design technologies
- Sep 22, 2023
- Special Talk: What is a Good Sound? [JAXA's No.92]
Current aircraft fly at about Mach 0.8, slightly slower than the speed of sound (Mach 1). Aircraft are a fast means of transportation, but it takes more than 12 hours to travel from Japan to Europe or the United States. If we could fly faster than the speed of sound, for example, twice as fast as current aircraft, flight time could be halved. This means that flights will take appropximately six hours from Japan to Europe or the United States.
If travel times are shortened, our society will be more secure and prosperous. For instance, economic activities such as business and tourism will become more active, and responses to emergencies such as natural disasters can be quicker. In addition, a flight duration of less than six hours reduces the risk of economy class syndrome, making travel more accessible for everyone.
Aircraft that enable such high-speed travel are called supersonic transports because they fly faster than the speed of sound.
Despite the significant benefits of supersonic transport, no subsequent supersonic civil aircraft have emerged since the retirement of the Concorde in 2003. The Concorde suffered from poor fuel consumption and very high operational costs. In addition, its loud sonic boom made it prohibited from flying suersonically over land, resulting in severely restricted flight routes. These factors contributed to the Concorde’s commercial struggles.
Research and development aimed at resolving these technical issues of the Concorde has progressed, and the momentum for the development of supersonic transport has been increasing since the 2010s. In response, the International Civil Aviation Organization (ICAO) has been discussing the formulation of international standards for sonic booms for supersonic flights over land.
The development of the next-generation supersonic transport through international cooperation is expected in the near future. JAXA will contribute to the progress of aircraft technology both in Japan and worldwild by presenting its own aircraft concept and demonstrating its technologies.
Conceptual illustration of supersonic transport applied with low boom design
Concept of small supersonic civil transport
As part of the S4 (R&D for System integration of Silent SuperSonic airplane technologies) program from FY2016 to FY2020, JAXA designed a conceptual aircraft for small supersonic civil transport, based on assumptions of Mach 1.6, 50 passengers, approximately 70-ton takeoff weight, and a cruising distance of 3,500 nm (about 6,300 km) or more. To achieve this aircraft concept, the key technical goals were determined.
Sonic boom
- When an aircraft flies at supersonic speeds, shock waves are generated from various parts of the aircraft. These shock waves integrate as they propagate over long distances in the atmosphere, creating an N-shaped pressure waveform that causes two abrupt pressure fluctuations on the ground. This phenomenon is known as a sonic boom, characterized by an impulsive, loud sound.
Supersonic projects
JAXA has been researching and developing key technologies for realizing a quiet and environmentally friendly next-generation supersonic aircraft, and has been implementing supersonic flight projects to demonstrate developed technologies.
Re-BooT project (FY2024-)
The Re-BooT (Robust en-route sonic-Boom mitigation Technology demonstration) project aims to demonstrate the robust low-boom design technology that makes all sonic booms heard on the ground quieter. We will demonstrate the robust low-boom design technology through flight tests and use the technology to design a concept aircraft of a quiet supersonic civil transport.
D-SEND project (FY2010-FY2015)
Through the D-SEND (Drop test for Simplified Evaluation of Non-symmetrically Distributed sonic boom) project, JAXA successfully proved that its design concepts and methodologies for a supersonic airframe configuration are effective in reducing sonic booms, a critical issue for future supersonic civil passenger transport. The objectives of the project included demonstrating the feasibility of the "low sonic-boom design concept" by flight tests and acquiring aloft sonic boom measurement techniques. The results from the project have been contributing to ongoing discussions on international rulemaking for sonic booms for next-generation supersonic aircraft.
NEXST-1 project (FY1997-FY2005)
In 2002 and 2005, JAXA conducted flight experiments of NEXST-1, a small supersonic experimental plane designed to improve fuel efficiency for supersonic flight, at the Woomer Test Range in Australia. The experiment successfully demonstrated that the low drag design concept applied to the experimental plane can reduce the air resistance by about 13% compared to that of the Concorde.
July 11, 2024