I would like to thank Stephen Hanson from the University of Leiden, author of the thesis “A Future Civil Supersonic Transport: Navigating the Legal and Environmental Headwinds”, for his support in the creation of this article.
In June 2025, the White House issued an executive order “Leading The World In Supersonic Flight”. Its purpose is to position the US as a leader in high-speed commercial aviation by updating standards and rules that have been in place since before the Concorde. It also encourages US companies, visionaries and engineers to undertake efforts toward delivering a new generation of high-speed aircraft.
This executive order means that some movement is taking place in the field of travel beyond the speed of sound in the USA. Will this become a trend in other parts of the World and what will it mean for international aviation?
First things first, “Regulatory Reform for Supersonic Flight”
According to the executive order, the Federal Aviation Administration (FAA) is expected to:
- Repeal the prohibition on overland supersonic flight by the end of 2025
- Repeal other regulations defining noise limits dating back to the 1970s
- Issue a Notice of Proposed Rulemaking (NPRM) by the end of 2026, to establish a standard for supersonic aircraft noise certification based on operational testing, research and development together with regular periodic review of the rules that will be reflecting future advancements in aircraft noise reduction technology.
Until today, we have seen a demonstration of the Boom XB-1, a one-third scale technology demonstrator for the planned airliner “Overture” reaching the speed of sound without creating a sonic boom. The aircraft was not designed to carry passengers, but its purpose was to test the technology before scaling up to the commercial jet. Another example, NASA’s Quesst mission, with Lockheed Martin’s X-59 aircraft, is planned to demonstrate technology to fly at the speed of sound and beyond, without generating sonic booms.
When it comes to international rules, the ICAO Annex 16 – Environmental Protection, Volume I – Aircraft Noise, contains a chapter about supersonic aircraft. However, it only includes noise standards for supersonic aeroplanes for which the application for Type Certificate was submitted before 1 January 1975. Currently, there are no Standards and Recommended Practices (SARPs) written for modern civilian supersonic aircraft regarding noise and works on these are ongoing at ICAO.
The Annexes to the Chicago Convention provide SARPs for the Contracting States, without interfering with States’ rights regarding their own airspace and airports. From a legal perspective, no international regulations stop States from allowing civilian supersonic flights to operate in their sovereign airspace. As we just saw in the example from the US, a State can change its national laws restricting supersonic flights. And the other way around, States that do not wish to open their airspace to supersonic aircraft have the right to do so.
The European Union Aviation Safety Agency (EASA) had been working on the issue of supersonic aircraft noise and launched a public consultation in 2022 on the environmental protection requirements for civilian supersonic flights. The Agency reviewed the consultation comments and decided to pause the development of European environmental certification requirements for supersonic flights in the near future, however it is currently contributing its technical proposals to the relevant ICAO working groups. In 2023, EASA explored the preparatory actions required for a future regulatory framework on Higher Airspace Operations (HAO), including supersonics and summarised these in their HAO Roadmap.
Civil Supersonic Flight – a matter of international dimension
The establishment of an international civil supersonic flight network will require a cross-border, coordinated effort. In densely populated Europe, with high environmental standards and sustainability ambitions, introduction of a commercial supersonic program would probably have to bring along a convincing business case to make the European organisations resume their work on developing rules for supersonics.
The executive order requires the FAA and heads of relevant US agencies to engage ICAO and international partners to work together on an international alignment regarding the regulatory approaches for supersonic commercial flights. These will include updating Bilateral Aviation Safety Agreements (BASAs) with foreign aviation authorities. In addition to airworthiness certification, BASAs provide for bilateral cooperation in a variety of areas, like maintenance, flight operations, and environmental certification.
The White House’s executive order has set the stage for regulatory reform and encouraged private innovation. Will we witness the dawn of a new era in aviation in the near future? It will depend on how well the world can align technological breakthroughs with coordinated development of regulatory and environmental frameworks rooted in countries’ sovereignty. Not mentioning the need for good economic justification for a new, undoubtedly costly supersonic programme.
